THE FERN GAZETTE is a journal of the British Pteridological Society and contains peer-reviewed papers on all aspects of pteridology. “Manuscripts may be submitted to: Dr M. Gibby, Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 SLR, UK Telephone: 013 1-248-2973 E-mail: FernGazette@eBPS.org.uk Instructions for authors are on page 50 of this volume and also available at http://www.eBPS.org.uk Books etc. may be sent for review to: Miss J.M. Camus, Department of Botany, The Natural History Museum, Cromwell Road, London SW7 5BD, UK Copyright © 2003 British Pteridological Society. All rights reserved. No part of this publication may be reproduced in any material form ‘(including photocopying or storing it in any medium by electronic means) without the permission of the British THE FERN GAZETTE Volume 16 Part 6, 7 & 8 was published on 2nd April 2003 Published by THE BRITISH foimry trae aa SOCIETY c/o ent of Botan The Natural History Museum, London ‘Sw7 5BD, UK Printed by Metloc Printers Ltd Old Station Road, setts Essex, IG1O 4PE, UK Cover design by Hazel Sims FERN GAZ. 17(1): 1-9. 2003 1 WHAT IS THE MINIMUM AREA NEEDED TO ESTIMATE THE BIODIVERSITY OF PTERIDOPHYTES IN NATURAL AND MAN-MADE LOWLAND FORESTS IN MALAYSIA AND SINGAPORE? F.B. YUSUF!, B.C. TAN! & ILM. TURNER2 'Department of Biological Sciences, The National University of Singapore, Singapore 119260; 2National Parks Board, Singapore Botanic Gardens, 1 Cluny Road, Singapore 259569 Key words: pteridophytes, species-area curve, natural forest. MeeR RR ROTANICAL Malaysia, Singapore ABSTRACT DEC 2 3 2003 The present studies show that in man-made forests, six 10 m x 10 ai RE ABRARY sufficient to give a good representation of the species diversity, as the comparatively uniform environment can provide a suitable habitat for only a limited number of species. Contrastingly, nine 10 m x 10 m quadrats are still not sufficient to capture the characteristic diversity of pteridophytes in natural forest habitats. This is due to the highly scattered distribution patterns of forest herbs, including the pteridophytes, along different gradients and microhabitats in the orest. In order to estimate the diversity of pteridophytes in natural forests more accurately, a minimal sample size of more than nine 10 m x 10 m quadrats needs to be established. INTRODUCTION Systematic collection and documentation of the diversity of pteridophytes in Singapore started as early as the 19th Century (Turner, 1994), and in Peninsular Malaysia in the early part of the 20! Century (Bidin, 1991). However, most of these studies concentrated on the taxonomy and species listings of pteridophytes. To date, few studies in tropical Southeast Asia have used quantitative methods to estimate the diversity of pteridophytes in a given area. Johnson (1969) appears to have been the first to conduct a quadrat survey of non-tree forest species (including pteridophytes) in this region. Her 15 quadrats in Taman Negara, Peninsular Malaysia, each of one square chain (about 0.6 km2), yielded a low number of 7 species of ferns and fern allies. A notable recent study by Sato ef al.,(2000) employed cubic quadrats of various sizes and numbers in an attempt to characterize the diversity of the pteridophyte flora in an oil palm plantation and three natural forests (Kepong, Pasoh and Semangkok) in Malaysia. Expectedly, the results showed that the number of quadrat cubes needed to capture the maximum pteridophyte diversity depends on the quadrat cube size used and the locally existing biodiversity. For the natural forest at Semangkok, 20 quadrat cubes of 20 m x 20 m x 20 m were needed to capture the high number of 40 species of ferns, whereas in the natural lowland forest at Kepong, the 20 quadrat cubes of 20 m x 20 m x 20 m captured a maximum number of about 28 species. In the oil palm plantation, 14 quadrat cubes of 20 m x 20 m x 20 m were needed to capture the maximum number of 18 species. 2 FERN GAZ. 17(1): 1-9. 2003 Since the objective of sampling, as opposed to documenting each and every species or individual, is to reduce the amount of labour and time involved (Chapman, 1976), the present study aimed to find out the minimum number of quadrats with a manageable area size of 10 m x 10 m that would be needed to estimate the pteridophyte diversity of natural lowland rain forest and man-made forests (oil palm and rubber plantations) in both Johor (Peninsular Malaysia) and Singapore. STUDY SITES AND METHODS Five sampling sites in natural and man-made forests in Johor (Peninsular Malaysia) and Singapore were selected for the present investigation. The two natural forests selected were the Gunung Pulai Forest Reserve [GPFR], situated inside the Gunung Pulai Recreation Forest (1° 36’N, 103° 34’E) in Johor, and the Bukit Timah Nature Reserve [BTNR] (103° 47’E, 1° 21’N) in Singapore. The man-made forests investigated were the oil palm and rubber plantations in the vicinity of Gunung Pulai Forest Reserve in Johor, and the rubber plantations on Pulau Ubin (1° 24’ N, 103° 58’ E), an island off mainland Singapore. These surveyed areas were chosen for their geographical proximity to each other, so as to eliminate the effect of climatic factors as a possible cause for the difference in the species diversity observed. Initially, six non-contiguous quadrats of 10 m x 10 m were established in each of the five study sites. The measurement of 10 m x 10 m was selected in consideration of the morphology and distribution pattern of the plant group to be sampled. According to Causton (1988), a quadrat size of up to 0.25 km? is suitable for the sampling of herbaceous vegetation. Since pteridophytes are comparatively not large herbaceous plants (with some exception, like Cyathea sp.), and after conducting a preliminary survey at the selected study sites, a quadrat size of 10 m x 10 m was deemed suitable for this study. In placing the quadrats, a ground survey of Gunung Pulai Recreation Forest was carried out and six seemingly undisturbed forested sites were selectively identified, each located within a reasonably homogenous topography. The non-random selective method was adopted where the quadrats were preferentially located by sight to ensure that at least one individual pteridophyte was present in each quadrat. This pre- determined layout of quadrats in the natural forests was aimed to maximize the capturing of diversity of pteridophytes using the minimal number of quadrats. In BTNR, the 2 ha permanent plot managed by the Smithsonian Institution and the National Institute of Education (NIE) was chosen to establish the six non-contiguous quadrats. Within the Smithosonian-NIE plot, the quadrat placement was similarly pre- selected in favour of the better portion of forest cover. In the case of the two types of man-made forests in Johor and Singapore, the location of the six non-contiguous quadrats in each of the three rather homogeneous study sites was also preferentially selected to maximize the inclusion of fern diversity within the quadrat. In actual observation, the non-random selection of quadrat site was found to be not necessary in the two types of man-made forests, the rubber and oil palm plantations, because of the similarity of pteridophytic flora found in situ. In all quadrats, the pteridophyte species within hand reach were recorded. Epiphytes of the high forest canopy that could not be collected from standing on the ground were excluded because the specimens could not be identified with certainty to the species even with field binoculars. The inclusion of epiphytic pteridophytes within the height of arm length in each quadrat is equivalent to, but not exactly comparable YUSUF et al.: BIODIVERSITY OF PTERIDOPHYTES 3 with, the quadrat cube method used by Sato er a/., (2000). The microhabitat conditions for each of the pteridophytic species collected were also recorded. To complete the diversity survey, additional collections were made from the general vicinity outside the six quadrats of each study site. After the quadrat samplings, voucher materials from each study site were prepared and identified in the Cryptogam Laboratory at the National University of Singapore and verified by comparison with authentic specimens preserved at SINU and SING herbaria. Finally, to estimate the minimum number of quadrats needed to characterize the pteridophyte species diversity in the different forest types, a species-area curve was generated for each of the five study sites. RESULTS The inventory of pteridophytes present in the six quadrats in each of the five study sites yielded 18 species in GPFR, 14 species in BTNR, 18 species in the oil palm plantations in the vicinity of GPFR, 13 species in the rubber plantations in the vicinity of GPFR, and 14 species in the rubber plantations in Pulau Ubin (Table 1). TABLE 1. Number of species, genera and families reported from the five study sites based on quadrat sampling. Habitat Natural Forests Man-made Forests Locality . . Oil palm Rubber Rubber Johor Singapore | plantation, plantation, | plantation, Johor Johor Singapore Species 18 14 13 14 Genera 16 ]2 ey 13 12 Families le 10 13 11 9 Interestingly, additional collections made from the general vicinity outside the quadrats in all man-made forests showed only a small increase in the number of species in comparison with the number of species found inside the quadrats. In the oil palm plantation, only two additional species (Selaginella willdenowii and Selaginella selangorensis var. ciliata) were added. Similarly, in the rubber plantations in Johor and Pulau Ubin, only one species each (Lindsaea ensifolia and Pteris semipinnata respectively) was not captured by the six quadrats. Contrastingly, while the number of species found in the six quadrats was 14 at BTNR and 18 at the GPFR (Table 1), the total number of pteridophytes reported for BTNR (Wee, 1995) and the collections made from the general vicinity of established quadrats in GPFR during this study produced a high total of 95 species for BTNR and 38 species for GPFR. The listing of species of ferns and fern allies collected from the quadrats of the two types of forests investigated is given in Appendix 1. Overall, the species-area curves generated for the five study sites (Figure. 1) showed an increase in the average number of pteridophyte species with the increase of the number of quadrats. However, the species-area curve for the oil palm and rubber plantations appeared to reach a plateau in its species number at the 6th quadrat. In contrast, the species-area curve for GPFR and BTNR continued to show an increase in species number up to the oth quadrat. The latter trend was observed with the addition of three more quadrats of the same size to the two forest sites (Figure. 2). 4 FERN GAZ. 17(1): 1-9. 2003 —x- Rubber Johor ++ BINR —O- Rubber Singapore —>- Oil Palm -ft— GPFR Average number of species 0 LJ t 7 t T 1 2 3 4 5 6 Number of quadrats (10 m x 10 m) Figure 1. Changes in accumulating number of pteridophyte species with increase in sample size (6 quadrats) in natural and man-made forests in Peninsular Malaysia and Singapore. DISCUSSION Results from this study show that a minimum of six quadrats of 10 m x 10 m is sufficient to capture the characteristic pteridophyte diversity in oil palm and rubber plantations in Johor and Singapore. This observation was confirmed when general collections made from outside the quadrats produced only two additional species in the oil palm plantation and one additional species each from the rubber plantations in Johor and Pulau Ubin. In man-made agroforests, like the oil palm and rubber plantations, it is not surprising that a small number of six quadrats is sufficient to capture the diversity of pteridophytes. Often, agricultural landscape is associated with homogeneity of the vegetation that consists frequently of monoculture with high habitat uniformity that lacks variation in its micro-habitats. This uniformity allows a limited suite of species to colonize and survive in a rather even and predictable distribution pattern. Furthermore, in the case of the man-made forests in Johor, the regular maintenance of the plantations in the form of weeding out the non-crop vegetation also attributes to the low diversity of the pteridophytic flora. YUSUF et al.: BIODIVERSITY OF PTERIDOPHYTES > “i GPrk. -L- BRINE Ne N o nn Average number of species — nN 10 5 0+ Ly ' LJ 7 i ' ee 1 Z 3 4 5 6 vi 8 9 Number of quadrats (10 m x 10 m) Figure 2. Changes in the accumulating number of pteridophyte species with increase in sample size (9 quadrats) in the natural lowland forest in GPFR and BTNR. The scenario appears to be different in natural lowland forests. In the case of lowland Dipterocarp forests at GPFR and BTNR, additional collections in the vicinity outside the six quadrats resulted in a notable increase in the number of species. Based on the general collections made in GPFR, the six quadrats captured only 32% of the known diversity of pteridophytes at GPFR. Likewise, only 13% of the BTNR pteridophytes reported by Wee (1995) were captured by the six quadrats. The addition of three more quadrats in GPFR and BTNR only increased the percentage of captured species diversity to 46% (26 species) in GPFR, and 22% (24 species) in BTNR. This indicates clearly that even nine quadrats of 10 m x 10 mare still far from adequate in giving a good estimation of the total pteridophytic diversity of the lowland rainforests in GPFR and BTNR. The big differences seen in the percentage of pteridophyte diversity captured by the same number of quadrats in the two natural forests (GPFR: 32% and 46%, BTNR: 13% and 22%) are partly due to the fact that the forested area surveyed in BTNR is ca 164 ha, while the forested area surveyed in GPFR during the present study is the 8 ha of core forest around the station office. In addition, the pteridophyte flora of BTNR has been explored, studied and documented for decades by the resident staff at the Singapore Botanic Gardens since the time of British rule, resulting in the large number of species recorded from this nature reserve. In the case of the latter, the present study is a first attempt to document the pteridophyte flora of the pristine forest reserve at GPFR in Peninsular Malaysia. The inadequacy of nine quadrats to estimate the total pteridophyte diversity of GPFR and BTNR can further be attributed to the patchy, widely spaced, and sporadic distribution pattern of pteridophytes in many lowland rain forests, making it difficult to capture the maximum representative diversity using a small quadrat size or a small number of quadrats. Understandably, the widely scattered pattern of distribution of pteridophyte species in the region is also a reflection of the heterogeneity of lowland rainforest. Similar patchy distribution in tropical rainforests is also observed in other ground vascular herbs (Kiew, 1978; Poulsen, 1996; Lum, 1999). 6 FERN GAZ. 17(1): 1-9. 2003 CONCLUSION For adequate estimation of the pteridophyte diversity in a man-made forest, such as the oil palm and rubber plantations in southern Malaysia and Singapore, a minimum number of six quadrats of 10 m x 10 m is sufficient. However, a total of nine quadrats of 10 mx 10 mis still insufficient to capture the overall pteridophyte diversity in the natural lowland forest in Johor (Malaysia) and Singapore. A minimum of more than nine quadrats of 10 m x 10 m is suggested for any similar studies in natural forests in the future REFERENCES BIDIN, A. 1991. Fern and fern-allies of Peninsular Malaysia, pp. 62—66. In: KIEW, R. (Ed). The state of nature conservation in Malaysia. Malayan Nature Society. CAUSTON, D.R. 1988. Introduction to vegetation analysis. Unwin Hyman. CHAPMAN, S.B. 1976. Methods in Plant Ecology. Blackwell Scientific Publications. JOHNSON, A. 1969. A forest quadrat in the National Park: the flora other than trees. Malayan Nat. J. 22: 152-158 KIEW, R. 1978. Floristic components of the ground flora of a per lowland rain forest at Gunung Mulu National Park, Sarawak. Pertanika 1: pe LUM, S. 1999. Tropical Rainforest, pp. 24-34. In: ie C. & CHEW, H.H. (Eds). State of the natural environment in Singapore. Nature Society, Singapore. POULSEN, A.D. 1996. Species richness and density of ground herbs within a plot of lowland rainforest in North-West Borneo. J. Trop. Ecol. 12: 177-190. SATO, T., S.L. Guan and A. Furukawa. 2000. A quantitative comparison of pteridophyte diversity in small scales among different climatic regions in Eastern Asia. Tropics 9(2): 83-90. TURNER, I.M. 1994. The inventory of Singapore’s biodiversity, pp. 47-52. In: WEE, Y.C. & NG P.K.L. (Eds). A First Look at Biodiversity in Singapore. National Council on the Environment, Singapore. WEE, Y.C. 1995. Pteridophytes, pp. 61-70. In: CHIN, S.C., CORLETT, R.T., WEE Y.C. & GEH, S.Y. (Eds). Rain Forest in the City: Bukit Timah Nature Reserve,Singapore. Gardens’ Bulletin Singapore Supplement 3. National Parks Board, Singapore. - rs ate ra - MOO (7) eounjads pidajospy - - + 4 - "MS DI/O{ISua DADSpUulT “ADIN IW “YOOH SuUassaAIp DODSPUlT por} qd b = 5 = a ee 304 (‘yOoH) DyAYydiy pI (pjnyda IG re fb + + = = WAN (J “uLIng ) DIDINI Uap Y1]JDADG OBIOLI| [PARC] + ‘ado (|g) pipjnuiwnds payjvAy - ‘ppog (yj ‘uung) szusnjod ly J os a oa 4+ - - - 5 - ‘edoy (4H) MUD] payJvAy ovaovoyyeAy +. + 4+ “ADID) 2 “YOOH juif wnuyoag "7 ajpjuatso ‘fo uinuyalg apoonuyso| q a +] + 1 ' i] . - % | ‘ds wniuajdsp ‘ID ‘QUNSNJAd “IRA “\SIO4 “D UNsaua) Wnivaldsp U ! ! ' +] + “7 snpiu wniuaydsy a + - rs - - Id Issisuo] WNIUA]dSP aeoovlua[dsy + ft "MS (PI[LA\) Saplouyoayg sian J + +}+ WS “f ([SO1g “D) P1/Ofiuust/p S ‘ a + = - yur] C7) DUIUDABOAA L f - - rs 4: “wey wniyofijp, unjubipy dBddEURIPY ne da dO UNL | addO LSAYOd LSauou HaVA-NVIA TWaatvNn SHIDddS GNV VaYANAD ATINVA SLVUGVNO YUSUF et al.: BIODIVERSITY OF PTERIDOPHYTES ‘(SOJOJ OPCUI-ULU UT sjerpenb g pur ysosoj [e.Njeu ul syeIpenb 6) Surjduies yeipenb uo paseq asodesuig pur (eiskejeyy Jepnsurudg) Joyor Ul s}so10J apew-ueU puke yeinyeu ul sa1sods a1Aydopuaid Jo uonnqiusiq *] xipusddy FERN GAZ. 17(1): 1-9. 2003 aa "MS (J) DIDILBIP DavZIYIS WIS (J) DuUOJOYIIP PaNZIYIS Z ds wniposay | ‘ds wniposaT "MS (J) wnsonxapf fo UNIPOBAT “MS (PILI) lwniyofisuo] (fo uniposAaT ‘ds snsosojpuAy Q dIOO[A, (CASI) DIADUAA UNSSOIBOUWAAT i Ad [Sold (7) am cE fe JOYIOID 2? JouUSeA “HM CARD) “anssnoiad 1qajydoiuo: m A> ‘ds sidajosyd UU], (°'T) Bypjnolind sidajosydan ee | WHRUAIBD wuNIPOdOIA ‘jadoy (ouIn|g) wnanosqo wnt c [ oa’ ‘dS WNIMOBOAIIA yosog f f ‘8. JOyIOID 2? Jouse AM “HM (CAIID) saplouysajg si4ajdoual) “MIOpUl) (J ULING) sLpaUt) $1.1) ‘jadog (Aad 2 ‘YOOH Xo ‘[[BM\) DrD}Oa | ‘jadoy (-YooH) Taqiog DIADJIA ] NOH ([SUd “D) SudjNGBIsdl DIMAUIOA | Oe da dO LSaYOd AGVIA-NVIN SLVUGVAO SH1adS UNV VaANAD ATUINVA YUSUF et al.: BIODIVERSITY OF PTERIDOPHYTES d10desulg ‘uonERUR]d Jaqgny fabs 1OYyor ‘uoNEULT Joqqny dul Joyor ‘uonejueyd wyed [IO dO QIOdVSUIS ‘AAIOSOY BINIBN YUL WYN UNL JOYOL ‘dAIOSOY SOO le[Ng sununhH Wddd vl el LI te SG Saloods Jo AquIN [0], - = - - sh ‘[q wnsOjUauUo] WURIZDIAIT : - - re - MOOW “L Clq) wnjpssasojpuasd unizpydiq IBIDBISPOO AA ea : f + 4, OO "MS DIDSUO]A DLADITL, . i" - : WOH Cof{uH] “eA siusofisua D1IADYL, - - + - - “MS STUMAO{ISUP DIADHL, IBIOVLICNTA, - - na ri MIOH (Ia) sn JaY4 souvydajso.iavyds | - ‘ + ca - WOH CMS) wanppAydiay wniaydauodg - - - - + WOH CMIOppy) wapunsigna unisydauodd - - - - of WIOH (S99) wruplép2zag uolgay WA . - - EN - ‘ds snuosojoay . : a : s MMOH (1a) jndqns Djjaistay) puardAlay | ; - - - + Jayeg (ASoq) WMouapyjiM Dj/aulsvjasy - - - + ea Buuids (“AdID 2M) Mysingxos Dpjaursyjas i [9S et: da dO UNLa | addO LSadOd LSAadOu AGVIACNVA | TVUALLVN Sd1I)ddS GNV VYANAD ATUIAVA SLVUaCVIO 10 FERN GAZ. 17(1). 2003 BOOK REVIEW A MODERN MULTILINGUAL GLOSSARY FOR TAXONOMIC PTERIDOLOGY. D.B. Lellinger. 2002. Pteridologia No. 3. Hardback. 264 pp., 15 figures (line drawings). ISBN 0-933500-02-5. American Fern Society, Inc. www.amerfernsoc.org Price US $28.00 + postage. The presentation of this book is clear and easy to follow. It comprises a numbered list of preferred terms and their definitions, with English, Spanish, French and Portuguese paragraphs for each term. Synonyms (about 100 for the c. 1000 distinct terms), antonyms and related terms are provided where applicable. Contents, introduction and comprehensive indices are provided also in each language. Finally, word lists of the terms defined in the book are offered for downloading from the American Fern Society web site for use as dictionaries in word-processing programs. I will quote from the introduction: “No attempt has been made to include archaic or obsolete uses or terms. All terms are defined as I believe they are currently used or should best be used. ... I have eliminated terms from the glossary that are difficult or impossible to define.” This is a worthy aim, but does imply that anyone looking for guidance to previously written fern descriptions may not find what they are seeking. When | first scanned this book, I wrote down a list of terms, definitions and miscellaneous observations that ‘hit a nerve’. Since then, I have gradually whittled down my initial objections. Some arose from my own misconceptions, and in this respect, the book has been useful to me. There is variation in the precision of definitions for some groups of terms. In the section on laminae, the definitions for 648 lobe and 655 segment are very precise, even to the selective use of “fully connate” (lobe) and “fully adnate” (segment), but definitions of 650 pinna, 651 pinnule and 652 pinnulet (a neologism) seem to be much less rigorous viz. for the latter ‘a petiolulate or sessile division of a pinnule that is at least narrowed at the base”. The characterisation of 613 phyllopodium as “that portion of the stipe” should perhaps be recast, to include the possibility that a rhizome outgrowth may instead be involved. The terms 677 anadromous and 678 catadromous are defined only in relation to a pinna, with the “basal pinnule and/or vein group of the pinna directed towards the frond apex [base]”. However, 496 dromy is defined more generally, and hence more correctly by reference to “basal axes or veins” and their relationship to “the second larger order of axes”. This latter phrase might be better as “the next higher order of axes”. With regard to spore formation, tetrad is defined (no. 764), but diad, as in some apomictic ferns, is not. erm 819 raphe refers to the rhizocarp of Marsilea, but rhizocarp is listed only as a synonym of 822 sporocarp. While on the subject of Marsilea, a definition is given for the specialised cells on the submerged lamina of ‘certain species’ (644 hydropote/hydropotes), but in the section on indument, I struggled to find any suitable term for the uniquely constructed hairs in this genus. This book is aimed at the Americas, not only in the choice of languages, but also the fern genera cited for some of the terms. On balance, I recommend this book to professional pteridologists, but I feel that the amateur would have valued the addition of explanatory illustrations and some sample descriptions. Peter D. Bostock FERN GAZ. 17(1): 11-19. 2003 11 MORPHOMETRIC ANALYSIS OF VARIATION AMONG THREE POPULATIONS OF DORYOPTERIS LUDENS (ADIANTACEAE: PTERIDOPHYTA) IN THAILAND T. BOONKERD Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailan (Email: Thaweesakdi.B@Chula.ac.th) Keywords. Adiantaceae, Doryopteris ludens, cluster analysis, canonical discriminant analysis, multivariate analysis. ABSTRACT Morphological variation within populations and among populations was examined in three populations of Doryopteris ludens from western and peninsular Thailand. Sixteen quantitative characters of both vegetative and reproductive characters were scored. The field data were analysed by means of cluster analysis and various discriminant analyses. Cluster analysis and canonical discriminant analysis indicated two groups. It is consequently concluded that there are two morphological varieties which that can be distinguished on the basis of sporangium length, sporangium width, fertile-frond sinus-depth, fertile-lamina width and habitat. A conventional identification key is provided, which is based on fertile-frond sinus-depth, sporangium length, and substrate conditions. INTRODUCTION Doryopteris is one of the smaller genera of the Pteridophytes. Tryon (1942) included 26 species in his revision of the genus. He also noted that Doryopteris is terrestrial, usually growing in rather dry, rocky places. Some species are extremely xeromorphic. Of the 26 species, there is only one species in Thailand, i.e. Doryopteris ludens (Wall. ex Hook.) J. Sm. as was enumerated in Flora of Thailand, volume 3 part 2 (Tagawa & Iwatsuki, 1985). This species is extremely variable in leaf form. The slender, elongate rhizome separates it from all other reticulate-veined species (Tryon, 1942) and it also differs from the closely related species D. pedata (L.) Fée in having a terete stipe. Geographically, this species is Asiatic, since its present distribution is confined to Myanmar, India, southern China and the Malay Peninsula, whilst the majority of Doryopteris species are American. Preliminary studies of herbarium specimens deposited at the following herbaria (abbreviations according to Holmgren et al., 1990):- Bangkok Forest Herbarium (BKF); the Professor Kasin Suvatabhandhu Herbarium, Department of Botany, Chulalongkorn University, Thailand (BCU); the Royal Botanic Gardens, Kew Herbarium (K) and The Natural History Museum, U.K. (BM), suggested that two forms of this species probably occurred, the normal and the dwarf forms. The normal form has a wider distribution throughout the country, occuring naturally in calcareous soils, in shady places in the dry evergreen forest, whilst the dwarf form is confined to the calcareous rocks of the limestone hills or limestone islands in peninsular Thailand. The specimens collected from Langkawi Island, Malaysia, and deposited at Kew 12 FERN GAZ. 17(1): 11-19. 2003 herbarium match well with this dwarf form. However, some additional field studies in peninsular Thailand revealed some morphological variations in characters related to size of frond within these dwarf form populations. There were still some overlaps in stipe length, lamina width and lamina length etc. between normal and dwarf forms, and so it remained unclear whether two forms could be recognized within this species. The present study is aimed at clarifying the taxonomic status of these two morpho- ecological forms of D. Judens by determining the levels of intra- and inter-population variation in the Thai populations. MATERIALS AND METHODS Plant materials Field collections of D. Judens were made during the rainy season to permit collection of complete specimens of both fertile and sterile fronds. Eighty-five specimens from three populations were sampled; the location, ecology and number of specimens are listed in Table 1. Sixteen quantitative characters of both vegetative and reproductive structures were measured or counted (Table 2). TABLE 1: Location, ecology and number of specimens of the three populations of Doryopteris ludens in Thailand. Population Location Ecology Number of specimens 1| Tub Sakae District, | Western Calcareous soil in shady 30 Prachuap Khiri Thailand places in dry evergreen Khan Province forest 2| Had Chao Mai Peninsular | Rock crevices, exposed or 30 District, Thailand partially shaded in Trang Province limestone hill 3} Muang District, Peninsular | Rock crevices, or on Pee Phangnga Province } Thailand humus-rich rocks, exposed or partially shaded in limestone islands Specimens examined a. Normal form Habitat: Terrestrial in tropical or evergreen forests at low or medium altitudes. Altitude : 100-1500 m. Distribution: India: Type: Wallich 88 (K); Isotype: Cuming 238 (K) Voucher: Thailand: North: R. Geesink & C. Phengklai 5949 (BKF), E. Hennipman 3029 (BKF), A.F'G Kerr 11365 (BK), Winit 1074 (BKF); North-Eastern: 7. Boonkerd 23, 269 (BCU), JF. Maxwell 76-325 (BK), M. Tagawa, K. Iwatsuki & N. Fukuoka 1254 (BKF); Central: Murata, Phengklai, Nagamasu & Nantasaen T-51409(BKF), J.F. Maxwell 73-522 (BK), A.FG Kerr 6029 (BK); East: J.F. Maxwell 74-978(BK), W. Somprasong 155 (BK); Western: K. Chandraprasong 61 (BK), K. Larsen & S.S. Larsen 33971 (BKF), A. Marcan 2696 (BM), Put 1430 (BK), T. Boonkerd 1122 (BCU); Peninsular: Ch. Charoenphol, K. Larsen & E. Warncke 3634 (BKF), E. Smith 2418A (BM), Put 1027, 1636, 3206 (BK, K), BOONKERD: DORYOPTERIS LUDENS 13 —=_—_—<—«—[—=—==—=C@VécaeE=EEL 3 3 3 i 3 i ————<=—— mm aaa) acai a) aD aa aaa Cams Soa) Ca ra T roy T ote i op T T 0.00 0.60 1.20 1.80 2.40 3.00 Average taxonomic distance Figure 1. Dendogram of Doryopteris ludens specimens b. Dwarf form Habitat: Terrestrial in rock crevice or on humus rich rock in limestone islands or limestone hill. Altitude : sea level to 250 m. Distribution: Malaysia: Langkawi Island: H.C. Robinson s.n. (K) Voucher: Thailand: South-Eastern: E. Smith 2417A (BM); Western: K. Larsen & S.S. Larsen 33688 (BKF), Put 250 (BK, BM, K); Peninsular: 4.hG Kerr 11365 (BK, K), Rabil 131(BK, K), T. Shimizu, N. Fukuoka & A. Nalampoon 7996 (BKF), 7: Boonkerd 151], 1443(BCU) Data collection and multivariate analyses To determine patterns of variation in D. /udens both a priori and a posteriori grouping systems were examined. First, the pattern of variation was examined by cluster analysis using the average taxonomic distance among the 85 specimens (Rohlf & Sokol, 1965). A sequential, agglomerative, hierarchical and nested (SAHN) clustering nested technique (Sneath & Sokal, 1973) was performed using the unweighted pair-group method with arithmetic averages (UPGMA) which is available in NTSYS-pc package version 2.0K (Rohlf, 1998). The purpose of this analysis was to place individual specimens (N=85) into groups (clusters) suggested by the data, but not defined a priori. Second, to determine whether morpho-ecological patterns existed from calcareous soil to calcareous rocks, each specimen was assigned to an a priori group based on its occurrence in natural habitat. 14 FERN GAZ. 17(1): 11-19. 2003 The SPSSpc-FW (Anonymous, 1997) was used to perform univariate analysis, stepwise discriminant analysis, classification discriminant analysis and canonical discriminant analysis. Stepwis? discriminant analysis was used to select a subset of characters that maximized differences among the a priori groups. Correct classification rates were used as indicators of separation among the groups. Canonical discriminant analysis was used as a dimension reduction technique to facilitate visualization of the results of the multivariate analysis. RESULTS Patterns of variation among specimens of D. /udens The SAHN technique generated a dendrogram which split the specimens into two groups (Figure 1). Specimens classified as group | in the cluster analysis consisted of all D. ludens from only population 1, whilst group 2 included members from both population 2 and population 3 which are rather separated into two subgroups. These two groups matched the morpho-ecological patterns of this species, i.e. normal form and dwarf form. However, the separation of group 2 into two subgroups suggested intra- and inter-population variation in the dwarf populations. Accordingly, three-clustering grouping were used in subsequent analysis as a posteriori groups. Sixteen characters were determined by stepwise discriminant analysis to be important in discriminating between the three groups. The following nine characters:- 4,5, 6, 8,9, 11, 13, 14, 15 were selected as important for giving the best separation of the groups (Table 3). In total, 97.6% of the specimens were classified correctly. These classification rates are extremely high considering that variation within the three populations existed. Ordination of the 85 specimens by canonical discriminant analysis was presented on the two canonical axes (Figure 2). This shows population | clearly separated from closely related population 2 and population 3 on axis 1. Thus the two morpho- ecological forms of D. ludens appear distinct. The nature of the group differences is characterized by the within-canonical structure (Table 3). Canonical variable 1 (axis 1) is most highly associated with characters 14, 15, 6, 5, 7, 3, 16 and 12 in descending order of the absolute values of the correlations (Table 3). The canonical correlation of the first canonical discriminant function is 98% correlated with all the variables and the variance explained by it is 93.5%. Thus this axis is effective for separating the two morpho-ecological groups of D. /udens. The F-values (Table 3) indicate by their magnitude the relative order of importance of the characters in general. It is clear that the F-values almost reflect the association of characters with canonical axis 1 because of its high correlation and high variance explained. Basic statistics of the three groups are also summarized in Table 3. It can be concluded that the vegetative characters of the normal form (population 1) were generally larger than the dwarf form (population 2 and 3). In contrast, the reproductive characters of the dwarf form were bigger than the normal form. In general, the means of the most important characters were significantly different, especially the four most important characters for axis | as can be seen from boxplots (Figure 3). DISCUSSION The results of cluster analysis, and canonical discriminant analysis support the recognition of separating the three populations of D. /udens into two distinct entities, probably as two varieties. The four most important characters (Table 3) that separate BOONKERD: DORYOPTERIS LUDENS Igqaweip sejod 10 Mata sejod wo as0ds Jo ysuoy (wu) Jajoureip d10ds 9] sIxe yeoyenba ay) Je WnisuRlOds JO dpIs 0) apis WO] PosNsvau doUR}SIP 1sasUO} (unl) YpiM tunisursods cl (yJeIS NOYyUM) WNIsuURIOds Jo do} 0) Aseq WOI PaiNseKa doUR}SIP JsaSUO] (win) sus] Winisuesods rl wumnisuelods jo do} ay} 1e poyenyts []99 snynuue ue Jo aseq 0} do} Wosy doUR)SIP (win) yoru) snynuue 7 puody apliays Jo adys Jo ysug] (wid) Yysudy odiys dp19)8 ZI dATPINpOAday PUOL d[LI9}S JO SNUIS JO dSeq PUR UISIJeW UddMJOq SDURYSIP | (WUD) YIdap snuIS puoIy d]110}s II puod d[L9Is JO BUTLUR] JO YPIM (WUD) YIPIM BUTLER] d]LIO}s Ol PUOLJ d][119}s JO RUILUR] JO Sago] JO SsoquINnuU JOquINu dqO] BUTLER] d{L191s 6 puody d]LI9}S Jo RUT] JO YYSuUd] (Wd) Ysud] BUILUR] 9]LI9)s g puoy spmtoy fo odys Jo ysuoy (wid) Ysa, ads apay L puoy ajay JO snuts Jo aseq pue UId.eU UDIMjOq DdURISIP | (Wd) yIdop snuIS puoy 91119] 9 puoy ofioy JO BUTUTE] JO WPI (WUD) IPPIM BUILUR] a]19J g puod] d]JOJ JO BUTI] JO Sogo] JO sJoquinu JOquINU ogo] BUILUR] d]II04 p puod d[1OJ JO vUILUR] JO YISUd] (Wud) Ysus] BUTLER] d]II04 ¢ puosy d[LI0}s Jo adyys Jo aseq ye AOJOWILIpP (WU) JaJOWUIRIp ddiys d]119}s ‘a puoy d[N40} Jo adnjs Jo aseq yw AQOWUeIpP (WW) Jo}OWRIP odijs apIA104 I IAIRIOGIA S}UNOD PUL SPUIWIINSKIU JO STIeIIG J9IBAIvYD JIquINy suapny staajdodsog JO Sisk[eue deVLUeAN[NU dy} UL posn suajoereyo [eordojoydow- *Z WIAVL 16 FERN GAZ. 17(1): 11-19. 2003 4 > ° 3 A a © 6 25 aA ° & aha ®& Maa a * a Se Re a © a “a a $ a = a > 3 © & ° A 0 O oo S -15 é a, 6) So % “2 - OG Centroids 2 " of O roup 0 O Population 3 35 O a © Population 2 O “— T : —_——s — ; cage ” 4 Population | -10 0 Canonical axis | Figure 2. Canonical discriminant analysis these two varieties are sporangium length (14), sporangium width (15), fertile-frond sinus-depth (6), and fertile-lamina width (5). However, fertile-frond sinus-depth (6) and fertile-lamina width (5) tend to be more important in the field for separating normal and dwarf forms of D. /udens as sporangium length (14) and sporangium width (15) are microscopic characters, only suitable for laboratory herbarium determination. These two vegetative characters are characters of leaf dissection as mentioned in Tryon (1942) in his revision of the genus. He noted that most of the species are quite variable in leaf dissection and should not be used alone as a diagnostic character in key construction, even as infraspecific determination, unless supported by additional characters. However, Tryon (1942) recognized the value of the sporangium stalk-length together with the leaf dissection characters to separate the species. Baum and Bailey (1994) used a series of discriminant analyses to determine taxonomic status of Hordeum caespitosum Scribner from different geographical ranges. They pointed out that for Hordeum a group of characters must be used together for identification, at least of the most important ones in the above sense. Speer and Hilu (1999) evaluated taxonomic status and determined quantitatively the importance of morphological characters that contribute to the discrimination between var. /atiusculum (Desv.) W.C. Shieh and var. pseudocaudatum (Clute) A. Heller of Bracken fern, Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) which is usually treated as a single species. They concluded that the treatment of the eastern North American bracken as var. latiusculum and var. pseudocaudatum seemed justifiable from the results of their study. BOONKERD: DORYOPTERIS LUDENS uonoury JURUTWULIOSIp Aue pure o]qeiueA YoRrd Ud9M4JOq UONLIILIOD aINjOSqe JsosIV] * y ‘stsAyeue astmdoys oy} UL pasn yOu JO}9RIBYO u £80 £18 bil OF'6 ILO 6S 0'0- *9 10 00°0 60S | ojourip-oiods *9 | STO} 8=—tO0T 0CO OFT vlO OSI £10 «PCO 00°0 199] tpim-uunisursods *¢ | coO = T cwO OO OLVE et EVE 970 *8P 0 00°0 69 F67 ysus}-uinisuesods *p | cLO 699 98°0 10°6 990 30S *9P 0) Ir'0 00°0 CLEC yoryy-snjpnuue “¢] IL¢v 91E€l S6¢b 8 Séel 169 8 C7C O10 *01'0- 00°0 70°97 »yisusy sdyjs-a[Lais *Z | 660 9FT [LO cle LST 99'S «170 61°0- 00°0 C6'6S yidap-snuls puoly-a]l49}s "| | tec )68=— BEG cs'l 68°L cOT }=-ER OI «PTO b0'0- Sc 0 cr I eYIPIM CUILUE]-d]LI9IS “(| 6S br C66 Lv’ LOSI OTT €OL +6 0 61°0 00°0 96°CS JOQUINU 9QO]-BUIWIE]-9]LI9}S “6 81C 8S°L TS I 0C'8 LOc OS FI *tb'0 87 0- 00°0 eT Cll sud] VUILUR]-d[LIAIS *g 618 pL vc S69 89°91 pOCI Pe 6t O10 «CC 0- 00°0 C8 tv ysua] odns-ajtay */ cr | 6S'°S S81 PI'S 2) ee ce 0 «Vt 0- 00°0 OS 1S1 idop-snuls puoly-d] 19} “9 OL'T ec Ol ert 9L°6 881 97 8I Sc 0 *9T 0- 00°0 8P'L8 UPIM BUILUL]-9[ TOF °C voL OOLI 89'S a oe Lvl *60'0- +00 SL‘0 Loz JOQUINU dqO]-BUILUR]-d]1I9J “fp y9'C STII cc t €S'6 itt 62 0c 910 *61°0- 00°0 8S trl Ysug] BUILUR]-O[ILOJ “¢ 70 SO'l 810 Ee | feo ei «170 t10- 00°0 16S] AAOWURIP Idiys-o]L19}s “7 | 80 Or'l S70 = 9E'T 810 681 «810 10°0 00°0 ES ep lo}oueIp adyjs-a] N49} | as uewop as. ueow as uvow ¢ uoneindog Z uonrndog | uonendog Z SIXV [| SIXy ‘qoig =| anpea-4 J9yB1eYyD suapn sisajdodsog Jo suoneyndod sary} dy) ul Gg ‘uRoW Jo AreWILUNS ‘sa[qeLUeA [eUISIIO oy) pue SO|QULIBA [ROIUOULD OM} JY} UDIMIOG SUONPIALIOD ‘sontiqeqosd Oy) YIM Son[eA-J pue dINJINIYs ;RITUOULI-UTYIIM PI]oOog %¢ WIAVA 18 FERN GAZ. 17(1): 11-19. 2003 3.0 2.5 sg E- E = = = 20 Es. E = a= ob gq 15 § 3 le a S| fs) s a. > ’ nm 1.0 9 5 N= 30 30 25 1 2 3 38 r: 16 G14 s 3 3 2 | 20 5 i = z° : = « - & 2 10 1 —_ <4 5 qu 32 oA vo “9 0 N= 30 30 25 N= 30 30 25 1 2 3 1 2 3 Population Population Figure 3. Boxplots of the four most important characters Key to identify the infraspecific taxa of D. luden Fertile-frond sinus-depth more than 7 cm; sporangium length 1.9-2.1 mm; plant growing in calcareous soils, in dense dry evergreen forest var. A (/udens) Fertile-frond sinus-depth less than 7 cm; sporangium length 2.5-3.7 mm; plant growing in rock crevices, exposed or partially shaded var. B CONCLUSION The results provided justification for the recognition of infraspecific variation among the three populations of D. /udens. In most cases they can be distinguished morpho- ecologically by their sporangium length, sporangium width, fertile-frond sinus-depth, ertile-lamina width and by their habitats (calcareous soils or calcareous rocks). However, this study is exploratory and further verification is required. ACKNOWLEDGMENTS Iam extremely grateful to Dr. Bernard R. Baum for his kind valuable comments on the manuscript. The work was partially supported by a grant from Chulalongkorn University, Bangkok, Thailand. I appreciate the field assistance of Rossarin Polawatn and assistance of Wanachai Chatan in the measurement of characters. This paper improved markedly from the comments of anonymous reviewers, to whom I am very grateful BOONKERD: DORYOPTERIS LUDENS 19 REFERENCES ANONYMOUS 1997. SPSS for Windows Release 7.5.2, Standard version, SPSS Inc.,Chicago. BAUM, B.R. & BAILEY, L.G. 1994. Taxonomy of Hordeum caespitosum, H. jubatum, and H. lechleri (Poaceae: Triticeae). Pl. Syst. Evol. 190: 97-111. HOLMGREEN, P.K., HOLMGREN, N.H. & BARNETT, L.C. 1990. Index Herbariorum. Part I: The Herbaria of the World. 8 Edn. I.A.P.T., New York Bot. Gard., New York: ROHLF, F.J. 1998. NTSYS-pe version 2.0k Numerical Taxonomy and Multivariate Analysis System. Setauket, Exeter Software, New York. ROHLF, FJ. & SOKAL, R.R. 1965. Coefficients of correlation and distance in numerical taxonomy. Univ. Kansas Sci. Bull. 45:3-27. SNEATH, P.H.A. & SOKAL, R.R. 1973. Numerical Taxonomy: The principles and practice of numerical classification. W.H. Freeman and Company, San Francisco. SPEER, W.D. and HILU, K.W. 1999. Relationships between two infraspecific taxa of Pteridium aquilinum (Dennstaedtiaceae). I. Morphological evidence. Syst. Bot. 23(3): 305-312. TAGAWA, M. & IWATSUKI, K. 1985. Pteridophytes. In: LARSEN, K. & SMITINAND, T. (Eds) Flora of Thailand of Thailand, vol. 3, part 2, The Chutima Press, Bangkok. TRYON, A.F. 1942. A revision of the genus Doryopteris. Contr. Gray Herb. 143: 1-80. 20 FERN GAZ. 17(1). 2003 e) You are invited to an International Pteridophyte Symposium eo) & FERNS FOR THE 21ST CENTURY @ & To be held at the Royal Botanic Garden Edinburgh, Scotland, UK ce = Monday - Friday, 12-16 July 2004 Ss With support of the Linnean Society of London 3 oS and the British Pteridological Society 1) ®) Organisers: Mary Gibby, Royal Botanic Garden Edinburgh © &) Paul Kenrick, Natural History Museum, London & &) Harald Schneider, University of Géttigen, Germany eo & Johannes Vogel, Natural History Museum, London I) & Keynote speakers or & Stephen Blackmore; Peter Crane; Mitsuyasu Hasebe; Kathleen Pryer; @) Gar Rothwell; Alan Smith 8 SS This will include sessions on Systematics and Macroevolution, Whole &%& 6S Genomics, Conservation, Ecological and Floristic studies, Fossils, SS 68, Development and Structure, Speciation and Microevolution. Workshops are %) ye Ss) proposed on Collections, Model organisms and Dating Fern Radiations. oo) &) Practical information 9) Ss) ccommodation will be available at Pollock Halls (Edinburgh University) &) & There will be the opportunity to visit the herbarium and living collections oo & at RBGE, and ferny sites close to Edinburgh. 2 <3 For further details, offers of talks or posters, please contact @ Carol Gibb, Royal Botanic Garden Edinburgh, 20A Inverleith s3 SS Row, Edinburgh EH3 5LR, Tel. +44 131 248 2957, Fax +44 131 8 3 248 2901, Email: pteridophytes@rbge.org.uk ot SS The British Pteridological Society is organising a Field Meeting in Scotland rool that will take place immediately after the conference. Spaces will be limited. @) fe) For further details contact Patrick Acock at Meetings@eBPS.org.uk & Se (one oo _ ofa. YL DLE SLE ALD TLE A AL ALS A AL GLO ALD NL LON, TX . TO SEER EEE EE IE OO OREO FERN GAZ. 17(1): 21-38. 2003 21 THE CURRENT STATUS AND DISTRIBUTION OF THE FALKLAND ISLANDS PTERIDOPHYTE FLORA D.A. BROUGHTON!.? & J.H. MCADAM?3 'Falklands Conservation, PO Box 26, Stanley, Falkland Islands, Fax: 00 500 22288, Email: conservation@horizon.co.fk; 2 Now at: Scott Wilson, 16 Priestgate, gees Cambs, PE] 1JA, Email: conservation@horizon.co.fk; *Department of Applied Plant Science, The Queen’s University of Belfast, Newforge Lane, Belfast, BT9 5PX, Northern Ireland., UK Email: jim.mcadam@dardni.gov.uk Key words: Falkland Islands, pteridophyte, fern, clubmoss, conservation, distribution, Lycopodiopsida, Pteropsida ABSTRACT The Falkland Islands are an archipelago of 782 islands situated in the South Atlantic Ocean. They have a relatively depauperate native flora of vascular plants comprised of 171 species, 18 of which are pteridophytes. The pterido- phyte flora includes a further three non-native taxa. Current knowledge of all pteridophyte taxa occurring in the Falkland Islands is reviewed and the first detailed data on their distribution throughout the archipelago are presented. INTRODUCTION The Falkland Islands are an archipelago of 782 islands situated in the South Atlantic Ocean approximately 520 kilometres east of mainland South America, and with a total land area of c. 12,200 km2. The climate is cool temperate oceanic, with a relatively modest seasonal variation. Temperatures are never high but are maintained at a moderate level with a mean for January of 9.4°C and a mean for July of 2.2 °C, with ground frosts occurring throughout the year. The Islands are subject to almost continual strong winds that come mainly from the southwest. The mean hourly wind-speed of 8.5 ms"! does not vary appreciably throughout the year though there is a greater frequency of stronger winds in spring and early summer. Rainfall is low with a mean annual precipitation, during the period 1944-1978, at Stanley of 640 mm, though the mean annual rainfall received tends to decline towards the south and west. Rainfall is lowest in spring and this combined with the strong winds reduces plant growth (McAdam, 1985; Summers & McAdam, 1993). Climatic variation across the Falkland Islands archipelago is poorly understood but climatic gradients are likely to be an important factor in determining the distribution of some plant species, notably some pteridophytes. The topography of the islands is not extreme with the landscape being generally hilly and the tallest mountain, Mt. Usborne on East Falkland, is only 705 m high. A typical Falkland soil has a pH in the range of 4.1 to 5.0 and comprises a shallow (typically no deeper than 38 cm) peaty horizon overlying a compact, poorly drained silty clay subsoil. Mineral soils occur in areas wherever the underlying geology is exposed, particularly on mountain tops and in coastal areas. The main vegetation of the Falkland Islands is acid grassland dominated by Cortaderia pilosa (d’Urv.) Hack. and dwarf shrub heath dominated by Empetrum rubrum Vahl ex Willd., but other vegetation types of more limited extent may be locally important particularly around the coasts. 22 FERN GAZ. 17(1): 21-38. 2003 There is no native tree cover. The main land use is sheep farming which is managed on an extensive, rangeland system. As a result, there are few areas in the islands that are not subject to grazing pressure for at least part of the year, though the potential negative effects of this for the pteridophyte flora appear to be minimal. THE PTERIDOPHYTE FLORA: AN OVERVIEW The 21 species of pteridophyte found in the Falkland Islands comprise a small but significant component of the 346 vascular plant species currently recorded for the archipelago. Of these, 18 species are native and represent 10.5% of the 171 native plant species. The pteridophyte flora is spread between two classes (Lycopodiopsida and Pteropsida), 10 families and 15 genera. The lesser of the classes, the Lycopodiopsida, comprises one family, two genera and three species, all of which are native. The Pteropsida come from nine families, 13 genera and 18 species, two genera and three species of which are non-native in origin having been introduced as garden plants. The Falkland Islands have no endemic pteridophytes, though Polystichum mohrioides (Bory) C. Presl. is restricted to the Falkland Islands and South Georgia and can be considered near endemic. A further species, Schizaea fistulosa Labill., has previously been reported for the Falkland Islands (Gaudichaud, 1825 cited in Moore, 1968). However, this record 1s based on the flimsiest of evidence and significant doubt is now cast on its validity. It appears the one and only record of this species for the Falkland Islands (Gaudichaud, 1825) was the result of a vague recollection of it having been encountered there. Given that no other records of this species in the Falkland Islands exist and given that Gaudichaud’s travels took him to places other than the Falkland Islands and that no herbarium specimen exists to support his claim, it now seems reasonable to assume that Gaudichaud was in error in reporting the species from the Falkland Islands and that the species has never been part of the flora (Skottsberg, 1913; Broughton, 2000). DISTRIBUTION OF PTERIDOPHYTE TAXA The Falkland Islands pteridophyte flora contains an interesting mix of common and rare species. The common species, such as Blechnum penna-marina (Poir.) Kuhn and B. magellanicum (Desv.) Mett., can generally be found wherever suitable habitat exists. The rare flora however, is much more exacting in its requirements, and is consequently vulnerable to disturbance and the destruction of populations. Clear trends can be discerned in the distribution of certain components of the pteridophyte flora both in terms of geography and ecology (though in many cases these are likely to be linked). Four (22%) of the native pteridophyte species - Adiantum chilense Kaulf., Blechnum cordatum (Desv.) Hieron, Rumohra adiantiformis (Forst. f.) Ching and Hymenophyllum tortuosum Hook. & Grev. - are currently known to occur only on West Falkland and the associated islands. Both Blechnum cordatum and Rumohra adiantiformis appear to be restricted to the northwest of West Falkland. Although variations in climate across the Falkland Islands archipelago are poorly understood it is known that West Falkland tends to benefit from a milder, drier and sunnier climatic regime, particularly in the northwest. As a result climate is likely to play a significant role in determining the distribution of these taxa. In comparison only one species, Botrychium dusenii (Christ) Alston, is currently known only from East Falkland. However, despite the rarity of this species the authors believe that it is likely to prove more widespread. It is perhaps no coincidence that the longest known population of this species is less than 3 km from the capital Stanley. The alien pteridophyte flora is also known only from the islands of West BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES 23 Falkland. As all three species are likely to have been introduced as garden plants this may be a reflection of where they were first introduced into the Falkland Islands. There is certainly evidence to suggest that wild populations of Dryopteris dilatata (Hoffm.) A. Gray may be descended from material cultivated in the gardens on West Point Island. With the exception of members of the Blechnaceae and the Lycopodiaceae most pteridophyte taxa appear to be largely absent from the dominant vegetation types of dwarf shrub heath and acid grassland, and this becomes more pronounced the further inland travelled. Even where species do occur in these dominant vegetation types, again with the exception of the Blechnaceae and Lycopodiaceae, they are generally so scarce as to suggest that some other ecological factor must be playing a significant role in determining distribution. In such species there is either a strong association with upland rocky habitats or with lowland habitats in close proximity to the coast. The distribution of the former group of species largely reflects the availability of suitable rock outcrops, and where suitable conditions occur in the lowlands they may be found here also, whilst the latter, which are often at the southern limits of their distribution in the Falkland Islands, probably require a milder climatic regime which can only be found in close proximity to the sea. It is only the common members of the Blechnaceae and Lycopodiaceae that are particularly widespread and occur in a wide range of habitats, and only Blechnum penna-marina can be considered a true generalist, being almost ubiquitous in all terrestrial habitats except wetlands proper, but including marginal vegetation. As a result Blechnum penna-marina is one of the most abundant plant species present in the Falkland Islands. Pulling together these data on the geography and ecology of Falkland Islands pteridophyte taxa it can be concluded that the highest diversity of pteridophyte taxa can be found where the coasts and lowlands meet rocky upland areas. This is clearly illustrated by comparing Figs. | and 2. Taken together, these show that the richest 10 km grid squares for pteridophytes are those in which the two highest peaks, Mt Adam (grid square TC88) and Mt Usborne (UC77), occur in close proximity to lowland areas. Ten pteridophyte taxa have been recorded for each of these two grid squares. Species diversity is lowest on the smallest islands and in much of the Lafonia region. Lafonia is notable for being low-lying and for the general absence of rocky outcrops, and it is this that is probably largely responsible for the low pteridophyte diversity. Another important factor may be summer drought stress and this is almost certainly responsible for the extreme scarcity of Blechnum magellanicum in this area (Figure 9). CONSERVATION RELEVANCE Falkland Islands pteridophytes as a group are of great concern to the national conservation strategy. Of the 28 plant species protected by law in the Falkland Islands (Falkland Islands Government, 1999) six (21% of protected plants and 33% of native pteridophytes) are pteridophytes (Table 1). Likewise, six species are listed as threatened (27% of threatened taxa and 33% of native pteridophytes, Table 1) in the National Red Data List (Broughton & McAdam, 2002) and Grammitis poeppigiana (Mett.) Pic. Serm. may be threatened but is currently listed as Data Deficient. A further species, Polystichum mohrioides, although not currently threatened, is also of conservation relevance. This species is believed to be restricted to South Georgia and the Falkland Islands and, as a result, the Falkland Islands may be responsible for a significant proportion of the world population. FERN GAZ. 17(1): 21-38. 2003 24 ‘(wepy “IA) puepyey samy pue (SUOgGsS/) “IAL) PuePA[ey \seq uo syeod ysoys1y oy) pue seore pueydn sofew oy) Sunensnyiy! osejodiyose spueysy] puepyye,z cya Jo dey] “] aansry puepyyey seq SONOW OL to dUINOGS(} “IW SONOU! YO = » © wepy IW ey 25 BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES ‘(soyAydopuayd 10} pakoains Ajayenbape oie daaijoq soy Ne ay} saienbs pls dsoy) 10} poyussaid A[UO eyep) sorenbs pus wy Q] [eNpIAIpUt Joy popsodos Ayissoarp aAydopiiojd yejo) oy) SuNesnyy! dey] *Z aans14 qAl ] _ Iz, an aijas Tt | > DA ; St fa, |-Apn alle By ey Pit aOR eS PAN, RRS a el vel ‘ Pal i aan eke ae balers eieierey TT erate [ziz| BS |/| fel [4] [etic [8 able |ziztez | lke OF] isl psea | [eoeey sl LA Fle ae ae nm bap ta : EQPB (8 |b, a] fy “Re al [UT _le Te fstlp wi 8 lolz+ a ital ra | ep EAE cclncal ee 2 ee oe: IP BHO") S SY ais pe, CAE TH TELE LN. LT I fi sh Bg (Ze A an ; 26 FERN GAZ. 17(1): 21-38. 2003 TABLE 1. Threatened Falkland Islands’ pteridophytes apes National IUCN Protected by law threat category Adiantum chilense Endangered yes Blechnum cordatum Vulnerable yes Botrychium dusenii Vulnerable yes Huperzia fuegiana Endangered yes Ophioglossum crotalophoroides Vulnerable yes Rumohra adiantiformis Endangered yes Grammitis poeppigiana Data Deficient no At present the conservation of threatened pteridophytes has progressed little beyond the recognition that they are of concern and the provision of legal protection. Much work is urgently required, particularly survey work, to locate and assess all surviving populations, research to determine their precise ecological niche within the Falkland Islands, publicity to raise the awareness of the identity and status of threatened pteridophytes on the farms in which they occur, the adequate protection of vulnerable populations and where necessary positive conservation action to ensure the survival and expansion of vulnerable populations. As a result the threatened pteridophytes of the Falkland Islands will provide an interesting conservation challenge for the future. SPECIES ACCOUNTS Accounts of all pteridophyte taxa present in the Falkland Islands are provided below. Nomenclature follows Zuloaga & Morrone (1996) and Pryer ef a/., (2001) and species are arranged by class and then alphabetically by family and genus. Reference is made to a voucher specimen held by Kew (K), or if not available, then the Natural History Museum (BM). National Red Data List categories, where assigned, follow IUCN (2001) and more detail on threatened pteridophyte taxa can be found in Broughton & McAdam (2002). Legal protection is provided by inclusion in the Conservation of Wildlife and Nature Ordinance 1999 (Falkland Islands Government, 1999). The maps presented illustrate the known distribution of each native species. They use all available records that can be assigned to one 10 km grid square (a lack of precision in some of the oldest records meant they could not be mapped). The maps only indicate presence in a grid square and the lack of a record from any particular grid square should not be used to infer absence of the species. However, trends can be identified in the distribution of many species and these are outlined in the species accounts and earlier sections. BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES 27 LYCOPODIOPSIDA LYCOPODIACEAE 1. Huperzia fuegiana (Roiv.) Holub 1985, Folia Geobot. Phytotax. 20: 72. Moore 1983: 46 as Huperzia selago. Figure 3. Habitat: Exposed situations without shrub overgrowth, such as rocky ledges, peaty hummocks around boulders, and sites where the growth of dwarf shrubs and other veg- etation is low and thinned by the presence of shallow underlying rocks. Altitude: 0-300 m (and probably higher). Distribution: Very locally distributed across the larger islands (Figure 3). Status: Native and rare. National Red Data List category: Endangered. Legal Status: Nationally protected. Voucher: Moore 533 (K). 2. Lycopodium confertum Willd. 1810, Sp. Pl., ed. 4, 5: 27. Moore 1983: 46. Figure 4. Habitat: More open facies of Empetrum rubrum heathland and Cortaderia pilosa acid grassland. Altitude: 0-650 m. Distribution: Widespread across the larger islands (Figure 4). Status: Native and scarce. This species seems to be naturally less abundant than the next species and this may be a result of the creeping growth-form, which may make plants less able to compete with other vegetation and thus dependent on more open con- ditions. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 587 (K). 3. Lycopodium magellanicum (P. Beauv.) Swartz 1806, Syn. Fil. 180. Moore 1983: 46. Fi Habitat: Empetrum rubrum heathland, Cortaderia pilosa acid grassland and inland rock habitats. Altitude: 0-610 m Distribution: Widespread across the islands (Figure 5). tatus: Native and common. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 716 (K). PTEROPSIDA ADIANTACEAE 1. Adiantum chilense Kaulf. 1824, Enum. Fil. 207 var. chilense. Moore 1968: 46.Figure 6 Habitat: Moist fissures and overhangs on sea cliffs, shaded from the mid-day sun, and within a few metres of the sea. Altitude: c. | m Distribution: Very locally distributed on West Falkland (Figure 6). Essentially a species of warmer climes it is at the southern and eastern limits of its natural distribu- tion in the Falkland Islands. It is currently only known from Saunders Island though it has been recorded more widely in the past. 28 FERN GAZ. 17(1): 21-38. 2003 Status: Native and rare. National Red Data List category: Endangered. Legal Status: Nationally protected. Voucher: Vallentin v.1911 (K). ASPLENIACEAE 1. Asplenium dareoides Desv. 1811, Ges. Nat. Freunde Berl. Mag. 5: 322. Moore 1983: 56. Figure 7. Habitat: Shady, humid crevices in rock outcrops and amongst boulders. Altitude: 155-460 m. Distribution: Locally distributed across the uplands of the larger islands (Figure 7). Status: Native and rare. Despite the apparent rarity of this species there is no reason to believe it is threatened. The preference for upland rocky habitats ensures the species is not currently threatened by human activities. The species may be under-recorded and more survey work is required. National Red Data List category: None. Legal Status: Not protected. Voucher: Vallentin xi.1910 (K). 2. Phyllitis scolopendrium (L.) Newman 1844, Hist. Brit. Ferns ed. 2: 10. Moore 1968: 4 8. Habitat: Inland rock. Altitude: Not known. Distribution: Very locally distributed in West Falkland. Two records exist, Mount Philomel area, West Falkland and Pebble Island (UD01). Status: Introduced, very rare. Last recorded 1994. National Red Data List category: None. Legal Status: Not protected. Voucher: Vallentin (K). BLECHNACEAE 1. Blechnum cordatum (Desv.) Hieron 1908, Hedwigia 47: 239. Moore 1968: 50-51 as Blechnum chilense.Figure 8. abitat: Empetrum rubrum heathland and Blechnum magellanicum stands. Altitude: c. 60 m. Distribution: Locally distributed in northwest West Falkland (Figure 8). The species is at the southern and eastern limits of its natural distribution in the Falkland Islands. Status: Native and rare to scarce. National Red Data List category: Vulnerable. Legal Status: Nationally protected. Voucher: Moore 858 (K). 2. Blechnum magellanicum (Desv.) Mett. 1856, Fil. Lechl. 1: 14. Moore 1983: 60. Figure 9. Habitat: Present in most terrestrial communities except wetlands and communities subject to drought stress. Large, dense stands are common at the base of rocky outcrops where water requirements are most easily met, and where humidity is relatively uniform. BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES 29 Altitude: 0-300 m. Distribution: Widespread across the islands. Largely absent from areas subject to summer drought stress such as the Lafonia region of East Falkland (Figure 9). Status: Native and common. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 771 (K). 3. Blechnum penna-marina (Poir.) Kuhn 1868, Filic. Afr. 92. Moore 1983: 60. Figure 10 Habitat: This species is a generalist found in all vegetation communities, except wetlands, but including marginal vegetation. On drier soils this species can dominate to the exclusion of all other taxa. Altitude: 0-705 m Distribution: Near ubiquitous throughout (Figure 10) and probably absent only from Beauchéne Island. Status: Native and very common. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 739 (K). DRYOPTERIDACEAE 1. Dryopteris dilatata (Hoffm.) A. Gray 1848, Man. Bot. North. U.S. 631. Moore 1968: 49 Habitat: Not known, probably associated with habitation. Distribution: Very locally distributed in northwest West Falkland. The herbarium material from West Point Island (TD40) collected by Sladen (see below) and cited by Moore (1968) was of cultivated origin Status: Introduced and very rare, last recorded 1909-1911 but may still persist. National Red Data List category: None. Legal Status: Not protected. Voucher: Sladen JB123/5 (BM). 2. Dryopteris filix-mas (L.) Schott 1834, Gen. Fil. 9. Moore 1968: 49. Habitat: Not known. Distribution: Very local, recorded from an unknown location in northern West Falkland. Status: Introduced and very rare. Reported only once and voucher material was not collected (Wright, 1911). The record should perhaps be treated with some caution. National Red Data List category: None. Legal Status: Not protected. Voucher: None available. 3. Polystichum mohrioides (Bory) C. Presl. 1863, Tent. Pteridogr. 83. Moore 1968: 48- 49. Figure 11. Habitat: Crevices in rock outcrops and among boulders, more rarely in dwarf shrub eatn. Altitude: 10-600 m (commonest in the uplands). 30 FERN GAZ. 17(1): 21-38. 2003 Distribution: Locally distributed across the larger islands, particularly the uplands (Figure 11). Status: Endemic to the Falkland Islands and South Georgia. The abundance of the species at any one site is dictated by the availability of suitable habitat, as a result it is generally scarce. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 924 (K). 4. Rumohra adiantiformis (Forst. f.) Ching 1934, Sinensia 5: 70. Moore 1968: 47.Figure 12 Habitat: Empetrum rubrum heathland and Blechnum magellanicum stands, more rarely on coastal cliffs. Altitude: 0-15 m. Distribution: Very locally distributed in northwest West Falkland (Figure 12). Status: Native and rare. National Red Data List category: Endangered. Legal Status: Nationally protected. Voucher: Moore 860 (K). GLEICHENIACEAE 1. Gleichenia cryptocarpa Hook. 1844, Sp. Fil. 1: 7. Moore 1983: 63.Figure 13. Habitat: Occurring either as pure stands or in Empetrum rubrum heath and Chiliotrichum diffusum scrub, it is most abundant where it occurs on loose sandy soils. Altitude: 0-150 m Distribution: Locally distributed on West Falkland, only one location known on East Falkland (Figure 13) Status: Native and locally common. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 787 (K). GRAMMITIDACEAE 1. Grammitis poeppigiana (Mett.) Pic. Serm. 1978, Webbia 32 (2): 455. Moore 1983: 50 as Grammitis magellanica f. nana. Figure 14 Habitat: Crevices on upland rock outcrops. Altitude: 18 5 m. Distribution: Very locally distributed in the uplands of the larger islands (Figure 14). Status: Native and rare? The species may be under-recorded and more survey work is quired. National Red Data List category: Data Deficient. Legal Status: Not protected. Voucher: Corner 333 (K). HYMENOPHYLLACEAE 1. Hymenophyllum caespitosum Gaudich. 1825, Annis. Sci. Nat. 5: 99. Moore 1983: 56 as Serpyllopsis caespitosa. Figure 15 BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES 31 Habitat: Inland rock outcrops and on moist peat at the base of such outcrops. This species seems the most tolerant of the three Hymenophyllum taxa to desiccation, and consequently can be found in more exposed, drought-prone situations where the other two species are absent. Altitude: 60-300 m. Distribution: Widespread across the larger islands, commonest in the uplands (Figure 15). Based on current experience, further survey work is likely to reveal this species to be present on most upland rock outcrops. Status: Native and common. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 802b (K). 2. Hymenophyllum falklandicum Baker 1874, in Hook. & Baker, Syn. Fil. ed. 2: 68. Moore 1983: 55. Figure 16. Habitat: Moist shady niches on rock faces and amongst boulders, more rarely on moist peat in Cortaderia pilosa acid grassland. Altitude: 0-515 m. Distribution: Widespread across the larger islands, commonest in the uplands (Figure Status: Native and scarce. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 802a (K). 3. Hymenophyllum tortuosum Hook. & Grev. 1829, Icon. Fil. 2: 129. Moore 1983: 53. Figure 17 Habitat: Inland rock outcrops. Altitude: 155-396 m Distribution: Locally distributed in upland areas of northern West Falkland (Figure 17) and likely to prove more widespread than current data would suggest. Status: Native and scarce. National Red Data List category: None. Legal Status: Not protected Voucher: Vallentin in 1909-11 (K). OPHIOGLOSSACEAE 1. Botrychium dusenii (Christ) Alston 1960, Lilloa 30: 107. Moore 1983: 47. Figure 18 Habitat: Short, open grassy turf and eroded areas on sandy soils near the coast. Altitude: c. 3 m Distribution: — locally distributed on East Falkland (Figure 18). Possibly over- looked at suitable sites elsewhere in the archipelago. Status: Native and rare. National Red Data List category: Vulnerable. Legal Status: Nationally protected. Voucher: Moore 530 (K). be FERN GAZ. 17(1): 21-38. 2003 2. Ophioglossum crotalophoroides Walt. 1788, F\. Carol. 256. Moore 1983: 47. Figure 19 Habitat: On peaty soils in Empetrum rubrum heathland and Cortaderia pilosa acid grassland. Altitude: 15-120 m. Distribution: Very locally distributed across the islands (Figure 19). atus: Native and rare. National Red Data List category: Vulnerable. Legal Status: Nationally protected. Voucher: Moore 636 (K). WOODSIACEAE 1. Cystopteris fragilis (L.) Bernh. 1806, Neues J. Bot. 1 (2): 27. Moore 1983: 56. Figure 20 Habitat: Moist shady crevices on rock outcrops. Altitude: 0-100 m. Distribution: Locally distributed across the islands (Figure 20). The distribution of the species is probably severely limited by a requirement for calcium and for conditions free from summer drought. Such conditions are uncommon in the Falkland Islands. Status: Native and scarce. National Red Data List category: None. Legal Status: Not protected. Voucher: Moore 639 (K). ACKNOWLEDGEMENTS This work would not have been possible without funding from the UK Government through the Darwin Initiative programme (Department for Environment, Food and Rural Affairs). We acknowledge the Falkland Islands Government for providing funding that has helped support the post of a full-time botanist in the Falkland Islands, allowing a third season of field research. We also commend them for acting to update the protected species legislation in line with the National Red Data List. Finally, we wish to thank all those who have contributed records to the vascular plant recording scheme. REFERENCES BROUGHTON, D.A. 2000. A note on the status of Comb-fern in the Falkland Islands. Falkland Islands Journal 7(4): 1-2. BROUGHTON, D.A. & MCADAM, J.H. 2002. A red data list for the Falkland Islands vascular flora. Oryx 36(3). 279-287. BROUGHTON, D.A., MCADAM, J.H. & BRANNSTROM, R. 2000. A combined checklist and ecogeographic conspectus for the vascular flora of Saunders Island, Falkland (Malvinas) Islands. Ans. Inst. Pat. Cs. Nat. Punta Arenas (Chile) 28: 57- 88. FALKLAND ISLANDS GOVERNMENT 1999. Conservation of wildlife and nature ordinance 1999. The Falkland Islands Gazette Supplement 10(18): 2-18. IUCN 2001. IUCN Red List categories and criteria: version 3.1. IUCN, Gland and Cambridge. BROUGHTON & MCADAM: FALKLAND ISLANDS PTERIDOPHYTES 33 MARTICORENA, C. & RODRIGUEZ, R. 1995. Flora de Chile 1. Universidad de Concepcion, Concepcion. MCADAM, J.H. 1985. The effect of climate on plant growth and agriculture in the Falkland eige Progr. Biometeorol. 2: 155-176. MOO 1968. The vascular flora of the Falkland Islands. Brit. Antarc. Surv. Sci. Rep. 60: He MOORE, D.M. 1983. Flora of Tierra del Fuego. Anthony Nelson, Oswestry. PARRIS, B.S. 1981. An analysis of the Grammitis poeppigiana - G. magellanica complex in the South Atlantic and South Indian Oceans. Fern Gaz. 12(3): 165-168. PRYER, K.M., SMITH, A.R., HUNT, J.S. & DUBUISSON, J. 2001. rbcL data reveal two monophyletic groups of filmy ferns (Filicopsida: Hymenophyllaceae). Am. J. Bot. 88(6): 1118-1130. SKOTTSBERG, C. 1913. A botanical survey of the Falkland Islands. K. Svenska Vetensk. Akad. Handl. 50(3): 1-129 SUMMERS, R.W. & MCADAM, J.H. 1993. The upland goose: a study of the interaction between geese, sheep and man in the Falkland Islands. Bluntisham Books, Bluntisham. WRIGHT, C.H. 1911. Flora of the ge Islands. Bot. J. Linn. Soc. 39: 313-339. ZULOAGA, F.O. & MORRONE, O. 6. Catalogo de las plantas vasculares de la Republica Argentina I Saher Gymnospermae y Angiospermae (Monocotyledoneae). Monogr. 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A ar | aah : wa FERN GAZ. 17(1): 39-51. 2003 THE IMPORTANCE OF RECENT POPULATION HISTORY FOR UNDERSTANDING GENETIC DIVERSITY IN THREATENED SPECIES, WITH SPECIAL REFERENCE TO DRYOPTERIS CRISTATA U. LANDERGOTT"!, G KOZLOWSKP,, J. J. SCHNELLER! & R. HOLDEREGGER? Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, CH-8008 Zurich, Switzerland; 2 Department of Biology and Botanical Garden, University of Fribourg, Ch. du Musée 10, CH-1700 Fribourg, Switzerland and 3Division of Biodiversity, Swiss Federal Research Institute WSL, Ziircherstrasse 111, CH-8903 Birmensdorf, Switzerland *Correspondence. Urs Landergott, Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, CH-8008 Zurich, Switzerland, Tel: +41 1 634 84 36, Fax: +41 1 634 84 03, e-mail: urs.landergott@gmx.net Key words: Dryopteris cristata, conservation, genetic bottleneck, genetic drift, genetic variation, population history, population size, spatial genetic substructure. ABSTRACT The maintenance of genetic diversity and stochastic losses of diversity during periods of small population size have become major points of concern in conservation biology. However, empirical research on random evolutionary processes in natural plant populations is still scarce and is reviewed here in comparison to our case study on Dryopteris cristata. Detailed recent population histories of this wetland fern have been documented in Switzerland. We found that the lack of correlation between present-day genetic diversity and current population size in this fern, as well as in other newly rare and endangered plant species, is best explained by recent population histories. Genetic diversity is strongly affected by genetic bottlenecks, which resulted in a loss of about 40% of genetic variation even in the long-lived allotetraploids D. cristata and a Hawaiian silversword. In contrast, distinct reductions in population size did not severely reduce genetic diversity in populations of the latter two species in the short-term. Accordingly, there was almost no spatial genetic substructure in populations of D. cristata. However, evidence for genetic drift was found in small populations of D. cristata and has also been reported for flowering plant species, indicating that small populations are nevertheless prone to random losses of genetic diversity in the long-term. This short review elucidates the importance of recent population history for both population genetics and conservation biology. Understanding population history can substantially improve predictions on the genetic diversity in remnant populations of threatened species. Further studies on natural populations of plant species with different life cycles and ploidy levels remain valuable. 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The maintenance of genetic diversity has consequently ecome a central focus of concern in conservation biology (Ellstrand & Elam, 1993). Resources for conservation efforts are limited, and accurate predictions regarding the genetic diversity in populations of threatened species are needed. In this context, the stochastic loss of genetic diversity during periods of small population size is an important factor (Barrett & Kohn, 1991). Genetic diversity has been found to be positively correlated with present-day population size in some plant species (e.g. Ellstrand & Elam, 1993; Raijmann ef a/., 1994; Fischer & Matthies, 1998). However, no such correlation has been reported for several rare and endangered species, and this outcome has often been suggested to be due to assumed changes of population size in recent population history (Ellstrand & Elam, 1993; Kull & Paaver, 1997; Kahmen & Poschlod, 2000; Lutz et al., 2000; Schmidt & Jensen, 2000; Fréville et al., 2001; Podolsky, 2001). As recent historical population sizes usually remain unknown, empirical research on the effects of genetic bottlenecks and drift on wild plant populations is almost lacking (Booy ef a/., 2000; but see Richards ef al., 2003). The stochastic loss of genetic diversity (specifically, allelic richness) associated with a bottleneck has been studied in artificially founded populations of Sarracenia purpurea (Schwaegerle & Schaal, 1979), the Hawaiian Mauna Kea silversword, Argyroxiphium sandwicense ssp. sandwicense (Friar et al., 2000) and Rutidosis leptorrhynchoides (Young & Murray, 2000). A distinct founder effect has also been reported for a population of Cypripedium calceolus, which existed for presumably no more than 200 years (Kull & Paaver, 1997), and for a single-founder population of Trifolium amoenum (Knapp & Connors, 1999). Accordingly, out of 13 studied populations of the locally rare Pedicularis palustris, lowest genetic variation has been reported for a nowadays large population of recent origin (Schmidt & Jensen, 2000). By comparing cytoplasmic diversity in a population of Thymus vulgaris before and after fire, Manicacci et a/., (1996) showed that disturbances may severely reduce genetic diversity. Founder effects may locally cause a shift from nucleo-cytoplasmic to purely cytoplasmic determination of sex and lead to high frequencies of females in colonising populations of the gynodioecious T. vulgaris (Manicacci et al., 1996). The stochastic nature of founding events has also been documented in Silene J/atifolia with younger populations displaying higher genetic differentiation than older ones (McCauley et ai., n common species with substantial gene flow among populations, however, genetic diversity can be restored rapidly with time after a founder event (von Fliie ef a/., 1999; Richards et al., 2003). In ferns, the relation between population history and genetic diversity has been discussed with respect to the colonisation of patchy rock habitats (Holderegger & Schneller, 1994; Schneller & Holderegger, 1996a; Vogel et al., 1999). Genetic diversity has been found to be positively correlated with population age in Asplenium ruta- muraria, indicating initial single spore colonisation and subsequent multiple colonisation events with increasing population age (Schneller & Holderegger, 1996a). Another opportunity for studying effects of recent population history on present-day genetic diversity is offered by the population dynamics of threatened species caused by man-made habitat disturbances. For the locally rare and endangered wetland fern Dryopteris cristata, recent population histories in Switzerland could be reconstructed LANDERGOTT et al.: DRYOPTERIS CRISTATA 43 (Landergott er a/., 2000) and present-day genetic diversity assessed (Landergott et al., 2001). Here, additional data are presented on the spatial genetic structure within populations of D. cristata. Our aim is to evaluate, illustrate and discuss the results of this case study from the perspective of conservation biology. We discuss implications for conservation in general by including comparable, but scarce, empirical studies on the influence of recent population history on present-day genetic diversity in newly rare and endangered plant species. DRYOPTERIS CRISTATA-SPECIFIC BACKGROUND The Crested Buckler fern, D. cristata (L.) A. Gray, has become rare and endangered in southwestern Central Europe (references in Landergott et a/., 2000). In Switzerland, at the southern border of the species’ European distribution, 22 (62% of all described) populations are extinct due to habitat destruction, and only 14 populations remained in 1999 (Map 1; Landergott et a/., 2000). The habitats of the surviving populations are best characterised as different remnants of formerly exploited, but not totally destroyed peat ogs. The commercial exploitation of peat bogs until approximately 1945 and their subsequent management as conservation areas caused substantial changes in population sizes of D. cristata. In a previous study, we reconstructed fluctuations in most of the Swiss populations of D. cristata over 120 years using herbaria and literature data (Landergott et a/., 2000). However, even for this attractive fern species, and in a study area with a rich floristic tradition, historical records of population sizes remained incomplete (Table 1). By including current population sizes determined in a field survey in 1999, it was nevertheless possible to establish three types of recent population histories: (I) the occurrence of a severe historical bottleneck of less than 25 individuals, (II) the reduction of a formerly large population (more than 300 individuals) to a small remnant (less than 150 individuals) before 1945 and (III) the increase of a formerly small population to a presently large one (Table 1; Landergott et a/., 2000). We estimated genetic diversity in 14 populations of D. cristata from Switzerland and southern Germany by random amplified polymorphic DNA (RAPDs; Landergott er al., 2001). In each of the 14 studied populations, 20 individuals were randomly sampled throughout the population area. This sample size is recognised as sufficient to provide accurate genetic diversity estimates for plant populations (Nybom & Bartish, 2000). RAPD diversity of D. cristata was extraordinarily low in the study area (for discussion see Landergott et al., 2001). However, the detected genetic variation within populations was not correlated with current population sizes (Figure 1; Table 1). In a hierarchical analysis of molecular variance (AMOVA), 15% of total variance was attributed to variation among three geographic regions (western and eastern Switzerland and southern Germany), 34% to variation among populations within regions, and only 51% to variation within populations. High population differentiation was indicated by a Fsr-value of 0.49 as well, and genetic divergence among populations was not correlated with geographic distances. These findings suggested very limited gene flow among populations of D. cristata. The absence of gene flow as an equalising force and the assumed selective neutrality of RAPD markers allowed us to investigate the effects of random evolutionary processes in recent population history on the genetic diversity in natural populations of D. cristata. Note that the categorisation of population size was deduced from the distribution of census numbers found in the studied populations (Landergott er al., 2000). Population size classes (Table 1) are thus somewhat arbitrary, and critical population sizes are likely to be different for other plant species with FERN GAZ. 17(1):39-51. 2003 44 ‘(1 21qeL, 99s suoNeIAdIqqe UoNL[ndod) sour] Japsog Plog PIM poyIVU ov STRNPIAIPUL CZ URY} Sso] JO SYIOUIT}0 [BOLIOISTY yUd901 YIM suoNefndod pue ‘punoidyorg Ass & YIM PoAv]JopUN sie s[eNplAIpUl CC] UY} a0 YIM suoHneindod as1e7] ‘suoneyndod Q[SuIs 0} poyOLysos a1oM sodAjouayd Aasd yep pue suoIsol a[SUIS 0} poyoLNsos oom sadAousyd Aas jury “SUOIBAI OMY UI Pa1NIIO sodXjousyd poyoyey ‘suoises yeorydes3009 dary) [[e Ul poznd90 sadAjouayd ary A, ‘(UMOYS JOU BIEP) [aM se AURLLLIAD WoyINos UI punoj oJ9M p] pure ¢ ‘¢ ‘7 ‘| ‘ON SadAjousyd Gg Ve (1007) “72 42 HOSIOpue’T O} SuIpsOIIe PUL]IAZIIME UJo}Seo PUP W9ISOM WOT pnysiao stuajdoduq Jo suoneyndod porpms ua} ay) ut sodAjousyd purg-nynw GqVey 9] JO uoNNqisip pue salouanbasy "] ans puvIozIMS UWOIsey | > | £ oI sl c val 94 ra ca I I cl i Pv cA bas ld J acre EIT PMA PTT TE RTE ERE NET TT SY e ¥ cM e IM resentment aca ene ew PUBLIOZIIMG UI9]S3\A LANDERGOTT et al.: DRYOPTERIS CRISTATA 45 different life histories and ploidy levels. As no information was available on historical population sizes of D. cristata from southern Germany (Landergott ef a/., 2001), the following considerations will focus on the ten Swiss populations included in the RAPD analysis (Map 1; Table 1). THE PAST EXPLAINS THE PRESENT In conservation biology, the number of multi-locus genotypes present in a population has been supposed to be a more important measurement of genetic diversity than the number of single variable markers (Schneller & Holderegger, 1996b). Molecular variance (Table 1) is based on genetic distances among RAPD multi-band phenotypes and on their numbers and frequencies (Excoffier et al., 1992; Fischer & Matthies, 1998), which are visualised for the ten study populations of D. cristata in Figure 1. Present-day RAPD diversity in populations of D. cristata was most prominently affected by recent historical genetic bottlenecks (population history type I; Table 1). In populations E3 and W1, severe bottlenecks were caused by peat exploitation. Only 20 individuals survived in population E3 in 1892, at the same place where we found 130 individuals in 1999 (Table 1; Landergott et a/., 2000). At Sales (population W1), D. cristata was considered to be abundant in 1905, but only a small population was reported in 1929, which then has been argued to become extinct due to further habitat destruction in the near future. By 1959, only two remnant individuals were reported from there, but in 1999 we found again 60 individuals at Sales (Landergott et a/., 2000). In contrast, genetic bottlenecks in populations E5 and E6 were most probably due to the recent establishment of new populations by a few founder individuals (Table 1). This could be inferred from the fact that both localities were thoroughly investigated before D. cristata had been reported there for the first time (Landergott ef al,, 2000). All four populations with recent bottlenecks were characterised by significantly decreased genetic variation, as compared to populations without bottlenecks (Table 1; U-test, P < 0.02; Landergott er al., 2001). Furthermore, the dominance of a widespread RAPD multi-band phenotype was a common feature of these recently bottlenecked populations of D. cristata (frequency of phenotype No. | 2 0.75 in all four cases; Figure 1). They comprised less rare RAPD phenotypes than most of the other studied populations (Landergott et al., 2001). The stochastic loss of genetic diversity during severe bottlenecks has been predicted by population genetic theory for diploid, outbreeding organisms (e.g. Barrett & Kohn, 1991). For polyploid species, however, less of an effect of a bottleneck on the genetic diversity would be expected, because high levels of segregational heterozygosity could nevertheless be maintained within populations (Barrett & Kohn, 1991; Bretagnolle et a/., 1998). In contrast, the four recently bottlenecked populations of the allotetraploid fern D. cristata (2n = 164) showed a substantial loss of genetic variation (reduction in molecular variance = 40%; Table 1) as compared to populations without bottlenecks. A similar loss of genetic diversity, as measured by the number of microsatellite alleles within population (reduction = 36%) and the proportion of polymorphic loci (reduction = 43%) has been reported in the allotetraploid Mauna Kea silversword A. sandwicense ssp. sandwicense after a genetic bottleneck of two individuals, which was associated with the populations re- introduction (Friar et al., 2000). In D. cristata from Switzerland, highest genetic variation was found in two currently small populations W2 and W4 (molecular variances = 0.534 and 0.734, respectively; Figure 1; Table 1). These populations were large ones at the beginning of 46 FERN GAZ. 17(1):39-51. 2003 the 20th century, but subsequently suffered a severe reduction in population size due to peat exploitation, leaving as few as 50 to 150 individuals of D. cristata in small marginal habitats by 1945 (population history type II; Table 1; Landergott er a/., 2000). Similar genetic variation was detected in a putatively old large population from southern Germany (B4, molecular variance = 0.655; Landergott ef al/., 2001). Unfortunately, there were no populations documented to have always been lage during the past 120 years, except for the geographically isolated population E4 (Landergott er al., 2001). However, the comparatively high molecular variance still maintained in the small populations W2 and W4 of D. cristata suggested that a distinct reduction in population size to less than 150 individuals did not substantially reduce genetic variation in populations of this long-lived, homosporous fern species in the short term. Similarly, a reduction in size to fewer than 50 plants in the remnant natural population of the long-lived Mauna Kea silversword was not accompanied by a significant loss of genetic diversity (Friar et a/., 2000). High genetic variation was also maintained in large and small remnants of formerly large metapopulation systems of Cypripedium calceolus (Kull & Paaver, 1997) and Pedicularis palustris (Schmidt & Jensen, 2000) and in fragmented subpopulations of Haplostachys haplostachya (Morden & Loeffler, 1999). In Clarkia dudleyana, a historically large but currently small population exhibited still high genetic variation, and classifying this population as either a small or large one has been reported to alter several trends of correlations between population size and various measures of genetic diversity (Podolsky, 2001). A prerequisite for the maintenance of a considerable amount of genetic diversity in small population-remains is the random distribution of genotypes within populations. For several predominantly outcrossing seed plants, weak spatial genetic structuring within populations has been reported (Heywood, 1991). Even less spatial genetic substructure would be expected in populations of long-lived, homosporous ferns, due to their high spore production and great potential for long-distance spore dispersal (Cousens, 1988). To get some insights into the spatial genetic structure within populations of D. cristata, we performed Mantel tests based on the spatial distances and the squared Euclidean genetic distances among the 20 RAPD phenotypes for each of the 14 studied populations separately (with 999 permutations using NTSYS-pc; Rohlf, 1998). A significant positive correlation was found only in the recently bottlenecked population E3 (Table 1; data of four German populations not shown). Because of the small sample size per population and because Mantel tests do not have high resolving power to detect spatial genetic structure within populations (Heywood, 1991), results should be interpreted with caution. However, at a larger spatial scale, they corroborate the proposed maintenance of considerable genetic variation in small remnants of formerly large populations of D. cristata. Furthermore, in small populations where a larger proportion of individuals has been sampled, they indicate little or no spatial genetic structure at the small scale. In contrast, positive autocorrelations have been observed at the small spatial scale in some populations of the rock fern species Pteris multifida (Murakami et al., 1997) and Asplenium trichomanes subsp. quadrivalens (Suter ef al., 2000). Further studies of spatial genetic structure and its relation to breeding systems in natural populations are needed for general predictions on the maintenance of genetic variation in small population-remains of ferns, but also in flowering plants (Stehlik & Holderegger, 2000). Despite the comparably high level of genetic variation maintained in some small populations of D. cristata, these populations could be prone to future stochastic losses LANDERGOTT et al.: DRYOPTERIS CRISTATA 47 of genetic variation through random genetic drift (Barrett & Kohn, 1991). A theoretical prediction on genetic drift states that allele frequencies within populations fluctuate and tend to drift apart, while overall average allele frequencies among populations remain constant (Hartl & Clark, 1997). In currently small and/or recently bottlenecked populations, deviations of RAPD marker frequencies within populations from their overall frequencies were in fact significantly increased, compared with marker frequency deviations in large populations (Landergott et a/., 2001). This gave evidence that small populations of D. cristata are actually under genetic drift, which might lead to random loss of alleles in the future. Severe genetic erosion due to drift occurred in the short term in small populations of the short-lived S. /atifolia when significant gene flow was absent (Richards ef al., 2003). Morden and Loeffler (1999) reported a substantial increase in the number of RAPD markers either present or absent in all individuals of the smallest subpopulation of Haplostachys haplostachya relative to other subpopulations, suggesting that drift was moving this subpopulation towards fixation of alleles. Kull and Paaver (1997) emphasised remarkable fluctuations of allele frequencies among isolated remnant populations of Cypripedium calceolus as well. urther evidence for genetic drift in small natural populations has been observed in Salvia pratensis and Scabiosa columbaria as judged from substantially higher genetic differentiation among small populations than among large ones (van Treuren et al., 1991). Accordingly, greater genetic differentiation among populations of Cyclamen balearicum from habitat islands in southern France than among populations from the true Balearic islands (Affre et al., 1997) has been attributed to genetic drift in small relict populations following habitat fragmentation in southern France in the past 500 years (Thompson, 1999). Finally, the intermediate level of genetic variation found in two of the largest populations of D. cristata, El and E2, could also be explained by their shared population history (type III; Table 1). These populations had first been recorded as small ones and substantially increased in size in the second half of the 20th century (Landergott ef al., 2000), presently showing high viability as indicated by spore production (Landergott, personal observation). Hence, ecological factors might be more important for short-term population viability in D. cristata than genetic diversity as assessed by neutral markers. Accordingly, viable populations with complete allozyme uniformity have been reported for the inbred, polyploid ferns Asplenium ruta-muraria, A. septentrionale and Polypodium vulgare (Schneller & Holderegger, 1996b). Notice that the relevance of neutral genetic variation for conservation purposes is presently under discussion (Crandall et al., 2000; Fischer et al., 2000; Podolsky, 2001), but in the end, adaptively significant genetic variation will be affected by stochastic losses during periods of small population size in much the same way as neutral variation. CONCLUSIONS As far as D. cristata is concerned, its extraordinarily low overall genetic diversity, somehow conflicting with its high genetic population differentiation, hinders straightforward conclusions for the species’ conservation. However, this fern is presently stated to be vulnerable (IUCN, 1994) in the region of western Switzerland (Landergott et al., 2000) and it is the focus species of a local conservation project at the Botanical Garden of Fribourg in Switzerland (Kozlowski, 1999). Without knowledge of possible adaptive differences among populations, the best strategy maintains genetically distinct populations. For example, in western Switzerland, the RAPD 48 FERN GAZ. 17(1):39-51. 2003 phenotypes of population W1 are a subset of W2 and, likewise, those of W3 are essentially a subset of W4 (Map 1; Figure 1). Preservation of genetic diversity in this region requires priority conservation of populations W2 and W4 (Figure 1; Table 1). Their small sizes make them prone to genetic drift, however, and in situ increases of their population sizes are thus desirable. Unfortunately, the autecology of D. cristata is poorly known (Page, 1997). Studies on its breeding system, safe sites, and recruitment of individuals in natural populations would considerably improve conservation strategies for this threatened fern species. In general, the studies reviewed in this article demonstrate the importance of recent population history for both population genetics and conservation biology. Especially in newly rare, threatened species, substantial recent historical changes in population size should be expected. Therefore, conservation practice requires an understanding of the effects of stochastic forces on genetic diversity (Barrett & Kohn, 1991), and theoretical predictions on random evolutionary processes during periods of small population size need to be tested in natural populations of plant species with different life histories and ploidy levels. Since population history is often incompletely known, the empirical base is still small and further case studies that consider genetic diversity in the light of population history will be most worthwhile. Floristic records in herbaria and in the literature, as well as continuous monitoring of small and large natural populations are important in this regard. If adequate records are available, population history can substantially improve predictions on genetic diversity in remnant populations of threatened species and thereby help in choosing priority populations for conservation. ACKNOWLEDGEMENTS We thank Austin Mast for stylistic improvements and helpful comments on a previous version of the manuscript. The Georges and Antoine Claraz-Foundation provided financial support for RAPD analysis of D. cristata. REFERENCES AFFRE, L., THOMPSON, J.D. & DEBUSSCHE, M. 1997. Genetic structure of continental and island populations of the Mediterranean endemic Cyclamen balearicum (Primulaceae). 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Spatial genetic structure and clonal diversity of Anemone nemorosa in late successional deciduous woodlands of Central Europe. J. Ecol. 88: 424-435 LANDERGOTT et al.: DRYOPTERIS CRISTATA er | SUTER, M., SCHNELLER, J.J. & VOGEL, J.C. 2000. Investigations into the genetic variation, population structure, and breeding systems of the fern Asplenium trichomanes subsp. quadrivalens. Int. J. Plant Sci. 161: 233-244. THOMPSON, J.D. 1999. Population differentiation in Mediterranean plants: insights into colonization history and the evolution and conservation of endemic species. Heredity 82: 2 6. VAN TREUREN, R., BIJLSMA, R., VAN DELDEN, W. & OUBORG, N.J. 1991. The significance of genetic erosion in the process of extinction. I. Genetic differentiation in Salvia pratensis and Scabiosa columbaria in relation to population size. Heredity 66: 181-189. VOGEL, J.C., RUMSEY, F.J., RUSSELL, S.J., COX, C.J., HOLMES, J.S., BUJNOCH, W., STARKS, C., BARRETT, J.A. & GIBBY, M. 1999. Genetic structure, reproductive biology and ecology of isolated populations of Asplenium csikii (Aspleniaceae, Pteridophyta). Heredity 83: 604-612. VON FLUE, I., GUGERLI, F., HOLDEREGGER, R. & SCHNELLER, J.J. 1999. Genetic and morphological variability in alpine Saxifraga oppositifolia L. after colonisation. Feddes Repert. 110: 555-559. O G. & MURRAY, B.G. 2000. Genetic bottlenecks and dysgenic gene flow into re-established populations of the grassland daisy, Rutidosis leptorrhynchoides. Aust. J. Bot. 48: 409-416. Fs FERN GAZ. 17(1). 2003 INSTRUCTIONS FOR AUTHORS PAPERS should not usually exceed 20 printed ee and are generally expected to be considerably shorter. Review articles, as well as reports of original research, are encouraged. Short notes are acceptable e.g. new pie sig The senior author should supply a fax and eMail address to facilitate correspondence. TYPESCRIPTS should be submitted in English (British), double spaced, preferably on A4 paper and in 10-point Times New Roman font. Two hard copies plus a PC version on disc (PC: WORD in WINDOWS) are required. All manuscripts will be refereed. THE TITLE should reflect the content of the paper and be in BOLD CAPITALS (11- point) and centrally aligned. Generic and specific names should be in italics and any title containing a generic or specific name must be followed by the family and Pteridophyta in brackets e.g. TRICHOMANES SPECIOSUM WILLD. (HYMENOPHYLLACEAE: PTERIDOPHYTA) IN SOUTHERN SPAIN AUTHOR ABBREVIATIONS should follow Pichi Sermolli's (1996) Authors of scientific names in Pteridophyta, Royal Botanic Gardens, Kew. MAIN HEADINGS: should be in BOLD CAPITALS (10-point) and centrally aligne SUBSIDIARY HEADINGS: should be in bold, the first letter of each word in capitals, the rest in lower case and left-aligned. AUTHORS' NAMES AND FULL ADDRESSES: follow the title and are centrally aligned. KEY WORDS: up to ten. ABSTRACT: should reflect the content of the paper. FIGURES: there is no distinction between photographs and line drawings in numbering. All should be presented in a form ready for reproduction, ideally in JPG format (please contact editor with queries), with a scale bar where appropriate. Lettering or numbers (Arabic) should be in the bottom left using uppercase Times Roman and be sufficiently large to be legible if reduction is necessary during printing. The number of photographs allowed in any one issue is limited by cost. Figure captions should be on a separate sheet. TABLES: can be printed in either portrait or landscape format. Authors should consider this when preparing tables. Authors should ensure that tables fit the printed page size in a legible form MEASUREMENTS: should follow the metric system. CHECKLISTS: should follow the format of Baksh-Comeau, Fern Gaz. 16(1, 2): 11- PZ. REFERENCES: should follow the style of a recent issue of The Fern Gazette, e.g.:- HOOKER, W.J. 1864. Species Filicum, 5. Dulau & Co., London. MORTON, C.V. 1947. The American species of Hymenophyllum, section Sphaeroconium. Contr. U.S. Natl. Herb. 29(3): 139-201 STEVENSON, D.W. & LOCONTE, H. 1996. Ordinal and familial —- TE of pteridophyte genera. In: CAMUS, J.M., GIBBY, M. & JOHN (Eds) Pteridology in perspective, pp. 435-467. Royal Botanic Gardens, Kew JOURNAL ABBREVIATIONS: should follow Botanico Periodicum Huntianum & Supplements. Alterations from the original text at proof stage will be charged for unless they are minor points of detail. Twenty-five offprints will be supplied free to the senior author. THE BRITISH PTERIDOLOGICAL SOC“™ Registered Charity No. 1092399 i | i Patron: HRH The Prince of Wales 17 Officers and Committee from March 2003 President: Prof. A.C. Wardlaw, 92 Drymen Road, Bearsden, Glasgow G61 2SY E-mail: President(@eBPS.org.uk Vice-Presidents: A.R. Busby, M.H. Rickard, Prof. B.A. Thomas, Dr T.G. Walker Honorary General Secretary: Miss J.M. Ide, 42 Crown Woods Way, Eltham, London SE9 2NN Tel./Fax: 020 8850 3218; E-mail: Secretary@eBPS.org.uk Treasurer: A. Leonard, |1 Victory Road, Portsmouth, Hants. PO! 3DR -mail: Treasurer@eBPS.org.uk Membership Secretary: M.S. Porter, 5 West Avenue, Wigton, Cumbria CA7 9LG Tel.: 016973 43086; E-mail: Membership@eBPS.org.uk Meetings Secretary: P.J. Acock, 13 Star — St Mary Cray, Kent BRS 3LJ E-mail: Meetings@eBPS.org.uk Conservation Officer/Recorder: R.J. Cooke, 15 Conduit Road, Stamford, Lincs. PE9 1QQ -mail: Conservation@eBPS.org.uk Editor of the Bulletin: Miss A.M. Paul, Department of Botany, The Natural History Museum, Cromwell Road, London SW7 5BD; E-mail: Bulletin@eBPS.org.uk Editor of the Fern Gazett Dr. M. Gibby, Royal Botanic Garden Edinburgh, L 20A havteloa: Row, Edinburgh EH3 5LR; E-mail: FernGazette@eBPS.org.uk 5 Editor of the Pteridologist: Dr J.W. Merryweather, The Farm,AttadaleStrathcarron, : Wester Ross [V54 8YX; E-mail: Pteridologist@eBPs.org.uk } Editor of BPS WWW Site - www.eBPS.org.uk: A.C. Pigott, Kersey's Farm, Mendlesham, ' Stowmarket, Suffolk IP14 5RB; E-mail: ep meagre org.uk Committee: S.E. Czeladzinski, Dr A.F. Dyer, Dr Y.C. Golding, M.L. Grant, Ms E. Knox-Thomas, S.J. Munyard, P.M. Ripley, RW. Sykes Booksales Organiser: S.J. Munyard, 234 Harold Road, Hastings, East Sussex ae aie E-mail: Booksal Horticultural Information Officer: R. Busby, 16 Kirby Corner Road, ‘Cantey, cue CV4 8GD; Pane i Archivist: A.R. Busby, 16 Kirby Corner Road, Canley, Coventry CV4 8GD; E-mail: Or ee org.uk Merchandise Organisers: Mr & Mrs B.D. Smith, Rookwood, | Prospect Rd, Oulton Broad, Lowestoft, Suffolk NR32 3PT; E-mail: Merchandise@eBPS.org.uk Plant Exchange Organiser: R.G. Ackers, Deersbrook, Horsham Road, Walliswood, Surrey RH5 5RL; E-mail: PlantExchange@eBPS.org.uk Spore Exchange Organisers: Mr & Mrs B. Wright, 130 Prince Rupert Drive, Tockwith, York YO26 7PU; E-mail: Spores@eBPS.org.uk Trustees of Greenfield & Centenary Funds: Miss J.M. Ide, A. Leonard, Prof. A.C. Wardlaw The BRITISH OLO I ee fern enthusiasts. It provides a wide range of inft f its ee tan and other literature. ap ashe pee miter Chyeuanienis, field meetings, genta: spvorsas exchanges, gardeners a £ ra t Th. CA i, fe - yp aes ta Preridologist and Bulletin, are aprons annually. The Fern Gazette deere matter chiefly of _—— RUN QULIMLY . FF ee WWW site: http://www.eBPS.org.uk - ‘Memberchin i: Ee See d fernalliee } : Ist January each yea) are Fal Personal } Members £20. Personal Memb t ivine the Fi Gi te £16 “ THE FERN GAZETTE VOLUME 17 PART 1 2003 CONTENTS What is is the minimum area needed to estimate the biodiversity of pteridophy natural and man e le d forests in Malaysia and 2: FB. Yusuf, B.C. Tan & 1.M. Turner “A. :a mR] eae = Morphometric analysis of variation among three populations of Doryopteris ludens (Adiantaceae: Pteridophyta) in Thailand T. Boonkerd . The current status and distribution of the Falkland Islands Pteridop D.A. Broughton & J.H. McAdam diversity in threatened species, with ial reference to Dryopteris cris U. Landergott, G. Kozlowski, J. J. Schneller & R. Holdereseer ee i