Bulletin of the British Museum (Natural History) Studies on the Old World species of Holothrips (Thysanoptera: Phlaeothripidae) S. Okajima Entomology series Vol54 Nol 26 March 1987 The Bulletin of the British Museum (Natural History), instituted in 1949, is issued in four scientific series, Botany, Entomology, Geology (incorporating Mineralogy) and Zoology, and an Historical series. Papers in the Bulletin are primarily the results of research carried out on the unique and ever-growing collections of the Museum, both by the scientific staff of the Museum and by specialists from elsewhere who make use of the Museum’s resources. Many of the papers are works of reference that will remain indispensable for years to come. Parts are published at irregular intervals as they become ready, each is complete in itself, available separately, and individually priced. Volumes contain about 300 pages and several volumes may appear within a calendar year. Subscriptions may be placed for one or more of the series on either an Annual or Per Volume basis. Prices vary according to the contents of the individual parts. Orders and enquiries should be sent to: Publications Sales, British Museum (Natural History), Cromwell Road, London SW7 5BD, England. World List abbreviation: Bull. Br. Mus. nat. Hist. (Ent.) © Trustees of the British Museum (Natural History), 1987 The Entomology series is produced under the general editorship of the Keeper of Entomology: Laurence A. Mound Assistant Editor: W. Gerald Tremewan ISBN 0 565 06024 4 ISSN 0524-6431 Entomology series Vol 54 No 1 pp 1-74 British Museum (Natural History) Cromwell Road London SW7 5BD Issued 26 March 1987 Studies on the Old World species of Holothrips (Thysanoptera: Phlaeothripidae) S. Okajima Laboratory of Entomology, Tokyo University of Agriculture, Sakuragaoka, Setagaya-ku, Tokyo 156, Japan Contents EN RRRI SES oe 9. 5. ABs Jada Sntentsn eatNee Mah dtadesakananawinendneaienad ASL iondeatetaedacwdehan PREEOMICTLOMM an de cspcceee sear snains fo aeee noe sii nails hens vin cre votaieciaclelsau dy weinas shine cdsledeviapeicwsjesioss ses Spaced Or te tribe DOCESSIsSOPHO CANIM 36 825. once dpiseeinncesenasnen vadvvsoninoonionswnaaseons RDN APAC CEES SULLCC Ceaeert esac teeta edited ta helo So ecinice cise gactodte suanied acasignuciase nichipitdeince 3 lA SHIT CIE ES Mere cnt re On Me Metseete isles cadens op ascasleanigt see cisctyasdeeess aides oneaieisneenns PRISE UTARIO SMe eee cn re nee ee eee o ota ailG aa sue aahied Toctarana sacs saseceoehavacesvecives Soa INSERM AYIN Gh ec ted ac tae ster sdasomen regs Sew ainqroa acini edenoavnacdasnswbeseddepseusanntcnes Rr TIG FALE AD AURTINSERALY ss sclieian coarse tastes vseadtenennSnsngpats avd Nine sroxtene a6eveyaucewesesacn Genus recalled from synonymy with Holothrips .................c0scecoececssceccececceesceseesers Taxonomy of the genus Holothrips from the Old World ....................cc0cceeceeeeeeeen eens ER CMREY EG OPAL VVONUSIIOINOS, ci os a diccav. chats care seavhicndcdiwbeywaveNcetadidad rodedyvenstvebescases Re IFRAMES, re Were asic coho cies idea didieth Rr Taewiaa eater Hae dpyacdnnncaph sve avandgaeck< 12 12 CILEIRET GS) CO Ro eae sneer ne oat CON ERE REE HERE Her cp R CEC EEE CRAG c CPEEE CE EERE nE CCerE Ee ERC Eee nES 54 CONNUMNNFHHRWNR Synopsis The systematic relationships of the genus Holothrips Karny and the tribe Docessissophothripini of the subfamily Phlaeothripinae are considered. One genus, Panceratothrips, is recalled from synonymy and transferred from the tribe, and two genera, Abiastothrips and Pseudosymphothrips, are placed in synonymy. Almost 50 species of Holothrips have been described from the New World; this paper includes descriptions of 49 new species and 6 new combinations, and provides a key to 69 Old World species and one Hawaiian species; a further three Old World species remain unclear and are excluded from the key. The species in the Docessissophothripini are all fungus-feeders, and are usually found on dead leaves and branches. Introduction The species of Holothrips are medium-sized tubuliferous Thysanoptera belonging to the tribe Docessissophothripini of the subfamily Phlaeothripinae. All the members of this tribe are fungus-feeders and are usually found on dead leaves and branches, but sometimes in grass tussocks or in leaf-litter. Most of the species in the Phlaeothripinae have slender maxillary stylets (1—3 wm) and, evenif they are fungus-feeders, there are no fungal spores in their gut. However, the stylets of the species in the Docessissophothripini are usually moderately broad (4—8 um) and their gut contents include small spores and even branched hyphae. The only other group of Phlaeothripi- nae with moderately broad maxillary stylets is the tribe Apelaunothripini (Okajima, 1979; 1984), but that may be distantly related because of the absence of the metathoracic sternopleural sutures. Because of the broad maxillary stylets, the genera in the tribe Docessissophothripini had been placed in the subfamily Idolothripinae (= Megathripinae) by several authors. Recently, however, Mound & Palmer (1983) transferred them to the Phlaeothripinae, and recognized nine genera in this tribe, redefining each genus with a checklist of included species. According to this work, there were 62 Holothrips species in the world, of which 18 were from the Old World and 44 were from the New World. However, in this paper, 54 species are added to the genus from the Bull. Br. Mus. nat. Hist. (Ent.) 54 (1): 1-74 Issued 26 March 1987 2 ; S. OKAJIMA Old World. Of this total of 72 Old World species, 13 are known only from single specimens, about 20 from 2—4 specimens, about 15 from 5—9 specimens and the others from more than 10 specimens. Moreover, inadequate material of more than 10 undetermined species from this region has also been examined, indicating that the study of the thysanopterous fauna of the Old World tropics and subtropics is far from complete. Most of the material used in this paper was collected recently from a few localities in South East Asia on a limited number of occasions. Moreover, there are wide areas in the Old World where the thysanopterous fauna is almost unknown, e.g. North and Central Africa, West Asia and New Guinea. This suggests that many more species remain to be found, possibly more than double the number of those included in this study. The tribe Docessissophothripini seems to be closely related to the genus Hoplothrips of the tribe Phlaeothripini (see below), but it is interesting that the species are somewhat different biologically from the species of Hoplothrips. In their distribution, the docessissophothripine species are mainly tropical and subtropical, with a few in the temperate zone. However, Hoplothrips species occur more in the temperate zone than the tropics, at least in the Old World. For example, eight Hoplothrips species have been recorded from England (Mound et al. , 1976) although only five have been recorded from India (Ananthakrishnan, 1973). Almost all the species of Hoplothrips show extreme allometry, particularly in the males, and the forelegs of the large males are distinctly enlarged. However, most docessissophothripine species do not show this type of size-related variation. Moreover, Hoplothrips species often produce large popula- tions under the bark of trees, whereas the docessissophothripine species rarely produce large populations. The present author considers that allometric growth may be related to colony size, because most of the tubuliferous species showing extreme allometry produce large populations or colonies. There is a possibility that allometric growth is not only the result of a difference in nutritive conditions, but also has an ecological or ethological significance. On the other hand, micropterae are very common in Hoplothrips species in both sexes and macropterae are sometimes rare, whereas micropterae have been discovered in only four Holothrips species in the Old World. Origin of the Tribe Docessissophothripini Mound & Palmer (1983: 90) redefined this tribe and transferred it from the Idolothripinae to the Phlaeothripinae, suggesting that it might be related to the tribe Phlaeothripini. The present author largely agrees with this opinion, although tribal relationships within the Phlaeothripinae remain unclear. The nominate tribe Phlaeothripini of the subfamily Phlaeothripinae is used here in a rather different sense from that of Priesner (1961: 290). At least the Hoplothrips-complex, placed by Priesner in a separate tribe Hoplothripini, must be included in the Phlaeothripini. Most of the characters defining the tribe Docessissophothripini are shared with those of the tribe Phlaeothripini. The only distinctive characters of the Docessissophothripini are the moderately broad maxillary stylets and the reticulated areas of the male on the intermediate (usually fourth to seventh) sternites (Figs 4-8). These sternal reticulated areas are somewhat similar to those of the Plectrothripini (Okajima, 1981). However, they are found in both sexes in the Plectrothripini, although only in males in the Docessissophothripini. Moreover, the form of the reticles is more or less different in these two tribes, suggesting that they are independent apomorphies. Recently, sternal reticulated areas have been found in males of Hoplothrips (Mound & Walker, 1986). These are quite similar to those of the Docessissophothripini, and it seems possible that they are homologous. In contrast, Hoplothrips species usually have a sternal glandular area on the eighth sternite in the male (Fig. 3), as is typical of Phlaeothripini, but the structure of this is distinct from the reticulated areas on the intermediate sternites. If the reticulated areas found on the intermediate sternites of male Holothrips and male Hoplothrips are really homologous, then there is a possibility that the Docessissophothripini is derived from Hoplothrips-like ancestors in the Phlaeothripini. The only apomorphy defining this tribe is thus the relatively broad maxillary stylets. Of nine genera recognized by Mound & Palmer (1983) in the tribe Docessissophothripini, STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS | four are restricted to the Old World; Maxillata and Pongola from South Africa, Asemothrips from Australia (one species, pallipes, from Java) and Oidanothrips from the Oriental Region. Three genera, Docessissophothrips, Symphyothrips and Tropothrips, are restricted to the New World (three Symphyothrips species described from the Old World, aberrans from India, alifanensis from Guam and longicauda from Baltic amber, may not be congeneric with the type-species). The remaining genus, Holothrips (with its synonym Abiastothrips), is widespread in the world. Moreover, this genus is large and includes more than 100 species, whereas the other seven genera are small, each with only a few species that can be distinguished from Holothrips only by rather weak characters. From this pattern of speciation, Mound & Palmer (1983) suggested that this tribe evolved relatively recently from the Phlaeothripini. Characters studied Head Head shape is an important character in identifying species or recognising relationships between species. The relative length/width, shape of cheeks, dorsal sculpture and median elevation are useful. Most species have the cheeks weakly and arcuately rounded, but some have almost straight or shallowly emarginate ones. However, shape is sometimes distorted by cover-slip pressure, and delicate care is necessary for study. Maxillary stylets are usually long, reaching eyes and close together in the middle of head, but sometimes not reaching eyes and more or less apart from each other. They are somewhat broader (4—8 um) than those of typical Phlaeothripinae (1-3 um). This condition may be assumed to be apomorphic. Maxillary guides are simple, but often bowed and distinctly developed. Sometimes they form a weak bridge (Figs 29, 33, 37, 39, 41, 44). Several species from South East Asia having this structure may constitute a natural group (apoensis-group, p. 17). Mouth cone shape is rather clearly divided into two types, rounded (short and obtuse in dorsal aspect) or pointed (long and acute in dorsal aspect); this is an important key character (key couplet 4). Setae are developed as in typical Phlaeothripini. Most species have a pair of long postocular setae, sharply pointed, expanded, knobbed or blunt at apex, rarely with two pairs in the New World species (undescribed species in BMNH). The ocellar setae are usually short, but a few species have well-developed anteocellar setae (e.g. subtilis, Fig. 154) or postocellar setae (Fig. 137). Cheek setae are usually weak. Antennae are seven-segmented, morphological segments VII and VIII fused, but usually with a suture, complete or incomplete, between them. One New World species, peruvianus, has segment VI broadly fused to VII. The relative lengths of the segments are sometimes useful for identification, but are often affected by sex and body size or allometric growth. The sense cone formula on segments III and IV is three and four respectively, but two New World species, phaeura and aberrans, have only two on III. Thorax Pronotum shape may be useful in recognizing relationships between species, but it is often affected by sex and body size. The relative length/ head length or / width, shape of anterior margin and the sculpture of the surface are considered in this study. Epimeral sutures are present posterolaterally on the pronotum, and usually complete. Setae on the pronotum are situated regularly. Five major setae are present, but the anteromarginal pair is sometimes reduced. The setal apices are variable in shape. Wings are usually present, micropterae being known in only four species in the Old World. Forewings, if well developed, have a series of duplicated cilia on the distal hind margin, but these exhibit a range of both intraspecific and interspecific variation. Forelegs have a tarsal tooth in both sexes. The shape is variable, small or large, curved or straight, wide-based or not, and sometimes is affected by sex and body size. The foretibiae rarely have a subapical tubercle at the inner apex, and the forefemora also rarely have a median 4 S. OKAJIMA tubercle (Fig. 187) or hump, which may be related to both allometric growth and sex. For example, the large males of cracens have a forefemoral median hump, but this is absent in the female and the small male (Ananthakrishnan, 1973). The enlargement and elongation of the forelegs in males related to allometric growth is usually less distinct than in Hoplothrips species. Abdomen Pelta (= first abdominal tergite) is usually bell-shaped or rather triangular, often hat-shaped, and a little broader than long. The shape and pattern of the sculpture is fairly stable within species and is sometimes useful in identification. A pair of the micro-pores is present or absent near the posterior margin of the pelta, and this is an important key character (key couplet 49). Tergites II to VII each bear two pairs of sigmoid wing retaining setae in macropterae, but sometimes the posterior pair on VII is reduced to being short and straight. Tergites II to IX each bear two pairs of major setae (B1 and B2) situated near the lateral angles, but those on tergite IX are situated medially (B1) and submedially (B2). The outside pair (B2) on tergite II is usually short and pointed at apex, but the others are well developed and their apices are variable in shape, sharply pointed, blunt, knobbed or expanded. The combination of shapes of these setae is often useful in defining species. In a group of several species from the New World, e.g. ingens (type species of the genus), these setae are flattened and remarkably wide, but this may be affected by sex because males of these species have these setae more slender. Tube shape is variable and important in defining species. It is usually straight-sided, but often weakly constricted near the base or apex, or somewhat heavy in several species. However, in most cases, this character does not seem to indicate relationships between species, thus suggesting homoplasy. The relative lengths of the tube and head are sometimes important in recognising relationships. Members of the apoensis-group (see p. 17), apparently a natural group from the Old World, have the tube longer than the head, whereas most other species have a shorter tube. The surface is usually smooth, but is sometimes sculptured with polygonal reticulation or longitudinal wrinkles. Sternal reticulated areas (Figs 4—8) are present or absent on the intermediate sternites (usually IV-VII) of the male, usually transversely developed, but sometimes reduced and divided into two parts. They are present in up to 60 per cent of those Old World species in which males are known. However, they are affected by body size or allometric growth. Measurements The relative length of head and tube are quite important for the identification of the Holothrips species. In this paper, the following standards were used. (In all cases care was taken not to measure specimens distorted by cover-slip pressure.) Length of head: from anterior margin of eyes to base at middle on dorsal surface (Fig. 1a). Width of head: maximum width across cheeks (Fig. 1b). Length of tube: from anterior margin to posterior margin of abdominal segment X on dorsal surface at middle (Fig. 2a). Basal width of tube: maximum width near base, excluding basal collar (Fig. 2b). Abbreviations The following abbreviations are used in the descriptions and the key. An: antennal segment n. MAn: morphological antennal segment n. POS: postocular setae. AA: antero- angular setae on prothorax. AM: anteromarginal setae on prothorax. ML: midlateral setae on prothorax. PA: posteroangular setae on prothorax. EPIM: epimeral setae on prothorax. DC: duplicated cilia on forewings. SWS: subbasal wing setae on forewings (SWSn, numbered from basal one). WRS: wing retaining setae on abdominal tergites. Sn: abdominal sternite n. Tn: abdominal tergite n. B1: inside pair of major setae at or near posterior margin on tergite. B2: outside pair of major setae at or near posterior margin on tergite. [B1(Tn): inside pair on tergite n.] L: length. W: width. The following abbreviations are used for the depositoriés. BMNH: British Museum (Natural History), London. CAS: California Academy of Sciences, San STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS 5 Francisco. SMF: Senckenberg Museum, Frankfurt. SO: S. Okajima collection, Tokyo University of Agriculture, Tokyo. TNA: Prof. T. N. Ananthakrishnan collection, Loyola College, Madras. Acknowledgements The author wishes to express his hearty thanks to many colleagues and curators for offering information or loaning specimens from their collections: T. N. Ananthakrishnan, Loyola College, Madras, India; F. A. Bianchi, B. P. Bishop Museum, Hawaii, U.S.A.; L. De Santis, Universidad Nacional de la Plata, R. Argentina; K. Haga, University of Tsukuba, Ibaraki, Japan; M. Hasegawa, Saitama, Japan; R. M. Johansen, Universidad Nacional Autonoma de Mexico, Mexico; N. Kashiwai, Tokyo, Japan; M. Miyazaki, National Institute of Agro-Environmental Sciences, Ibaraki, Japan; L. A. Mound, BMNH, London, U.K.; S. Nakahara, United States Department of Agriculture, Maryland, U.S.A.; J. M. Palmer, BMNH;; W. J. Pulawski, California Academy of Science, San Francisco, U.S.A.; M. Saikawa, Kanagawa, Japan; K. Sakimura, Hawaii, U.S.A.; S. Sen, Zoological Survey of India, Calcutta, India; T. Senoh, Tokyo, Japan; W. Suzuki, Tokyo, Japan; M. Tomokuni, National Science Museum, Tokyo, Japan; D. Voegtlin, Illinois Natural History Survey, Urbana, U.S.A.; R. zur Strassen, SMF, Frankfurt, West Germany. Thanks are also due to Professors H. Sawada and Y. Watanabe, Laboratory of Entomology, Tokyo University of Agriculture, for their constant guidance. This study could not have been completed without the cooperation of Dr L. A. Mound on various matters, particularly his expert suggestions after reading through the manuscript. Nomenclatural summary Taxa transferred from Holothrips PANCERATOTHRIPS Bagnall, 1936 gen. rev. typicus Bagnall, 1936 Holothrips from the Old World HOLOTHRIPS Karny, 1911 Trichothrips (Abiastothrips) Priesner, 1925 syn. n. Lathrobiothrips Karny, 1933 Adelothrips Hood, 1938 Cordylothrips Hood, 1937 Ischnothrips Moulton, 1944 Agnostothrips Moulton, 1947 Pseudosymphothrips Kurosawa, 1954 syn. n. Agnostothrips (Erythrinothrips) Ananthakrishnan, 1956 Stinothrips Ananthakrishnan, 1969 Holmiella zur Strassen, 1972 africanus sp. n. ananthakrishnani sp. n. andamanensis (Sen, 1980) comb. n. andrei sp. n. angulatus (Priesner, 1927) comb. n. angulus sp. n. antennalis sp. n. apoensis sp. n. armatus sp. n. attenuatus sp. n. australis (Mound, 1974) breviceps sp. n. brevicollis sp. n. brevitubus sp. n. castanicolor sp. n. caudatus (Bagnall, 1915) celebensis sp. n. cephalicus sp. n. citricornis (Bagnall, 1913) cracens (Ananthakrishnan, 1968) cupreus sp. n. curvidens sp. n. falcatus sp. n. flavicornis sp. n. flavitubus sp. n. flavus sp. n. formosanus sp. n. fumidus (Ananthakrishnan, 1972) hagaisp. n. hasegawai sp. n. indicus (Ananthakrishnan, 1956) associatus Ananthakrishnan, 1968 japonicus sp. n. kuntiae (Sen, 1982) comb. n. latidentis sp. n. luteus (Faure, 1954) Juminosus sp. n. maxillae sp. n. mirandus (Ananthakrishnan, 1969) moundi sp. n. nepalensis (Pelikan, 1970) nigripes sp. n. nigritus (zur Strassen, 1972) oceanicus sp. n. ogasawarensis sp. Nn. okinawanus sp. n. parallelus sp. n. peltatus sp. n. peninsulaze sp. n. pictus sp. n. porifer sp. n. pulchellus sp. n. quadrisetis sp. n. ruidus (Ananthakrishnan, 1969) ryukyuensis sp. n. sakimurai sp. n. sawadai sp. n. schaubergeri (Priesner, 1920) comb. n. priesneri Bagnall, 1933 lativerticis Post, 1961 semiflavus (Moulton, 1947) setosus sp. n. soror (zur Strassen, 1974) comb. n. speciossissimus (Karny, 1920) stannardi (Ananthakrishnan, 1972) storkisp. n. subtilis (Ananthakrishnan, 1972) tibialis sp. n. titschacki (Priesner, 1928) f. debilis Priesner, 1928 torajanus sp. n. torosus sp. n. typicus (Ananthakrishnan, 1967) unicolor sp. n. yuasai (Kurosawa, 1954) comb. n. yurikoae sp. n. zimmermanni (Moulton, 1944) S. OKAJIMA STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS Ti Genus recalled from synonymy with Holothrips PANCERATOTHRIPS Bagnall gen. rev. Panceratothrips Bagnall, 1936: 219-220. Type-species: Panceratothrips typicus Bagnall, by monotypy. [Synonymized with Polyphemothrips Schmutz by Mound, 1968: 146, and with Holothrips Karny by Mound & Palmer, 1983: 92.] Mound (1968: 146) and Mound & Palmer (1983: 92) synonymized this genus with Polyphemothrips and Holothrips respectively. However, the long maxillary stylets of typicus, type-species of the genus, are narrower than those of docessissophothripine species, and do not differ from those of typical Phlaeo- thripini. Since the tribe Docessissophothripini is here distinguished from the tribe Phlaeothripini only by the moderately broad maxillary stylets, Panceratothrips is placed in the tribe Phlaeothripini. Panceratothrips typicus Bagnall Panceratothrips typicus Bagnall, 1936: 220. Lectotype 2, MapaGascar (Muséum National d’Histoire Naturelle, Paris) [1 2 paralectotype examined]. Polyphemothrips typicus (Bagnall) Mound, 1968: 146. Holothrips typicus (Bagnall) Mound & Palmer, 1983: 95. The seventh and eighth antennal segments of this species are fused completely as in the Docessissophothri- pini, but this feature is also found in many other phlaeothripine genera. MATERIAL EXAMINED Madagascar: 1 9 (paralectotype), Province of Tanarive, 1905 (A. Mathiaux) (BMNH). Taxonomy of the genus Holothrips from the Old World HOLOTHRIPS Karny Holothrips Karny, 1911: 502; Mound & Palmer, 1983: 92-95. Type-species: Holothrips ingens Karny, by monotypy. Trichothrips (Abiastothrips) Priesner, 1925: 153. Type-species: Trichothrips schaubergeri Priesner, by original designation. [Raised to genus by Priesner, 1927: 556.] Syn. n. Cratothrips Priesner, 1927: 494-495. Type-species: Cratothrips angulatus Priesner, by monotypy. [Synony- mized with Abiastothrips Priesner by zur Strassen, 1974: 119-120. ] Lathrobiothrips Hood, 1933: 421. Type-species: Lathrobiothrips ramuli Hood, by monotypy. [Synony- mized by Mound & Palmer, 1983: 92.] Cordylothrips Hood, 1937: 517-518. Type-species: Cordylothrips peruvianus Hood, by monotypy. [Synonymized by Mound & Palmer, 1983: 93.] Adelothrips Hood, 1938: 380. Type-species: Adelothrips xanthopus Hood, by monotypy. [Synonymized by Mound & Palmer, 1983: 93.] Ischnothrips Moulton, 1944: 305. Type-species: Ischnothrips zimmermanni Moulton, by monotypy. [Synonymized by Mound & Palmer, 1983: 93.] Agnostothrips Moulton, 1947: 172-173. Type-species: Agnostothrips semiflavus Moulton, by monotypy. [Synonymized by Mound & Palmer, 1983: 93.] Pseudosymphothrips Kurosawa, 1954: 134. Type-species: Pseudosymphothrips yuasai Kurosawa, by monotypy. Syn. n. Agnostothrips (Erythrinothrips) Ananthakrishnan, 1956: 341. Type-species: Agnostothrips (Erythri- nothrips) indicus Ananthakrishnan, by monotypy. [Raised to genus by Ananthakrishnan, 1964: 94; synonymized by Mound & Palmer, 1983: 93.] Stinothrips Ananthakrishnan, 1969: 55. Type-species: Ischnothrips typicus Ananthakrishnan, by mono- typy. [Synonymized by Mound & Palmer, 1983: 93.] Holmiella zur Strassen, 1972: 95-98. Type-species: Holmiella nigrita zur Strassen, by monotypy. [Synony- mized by Mound & Palmer, 1983: 93.] Diacnosis. Colour yellow to dark brown, usually with red hypodermal pigments. Head usually longer than broad, sometimes elevated dorsally, dorsal surface partly or generally sculptured. Antennae 7-segmented; MA7 and MA8& completely fused, but usually with a complete, incomplete or reduced suture between them; A3 with three sense-cones, A4 with four sense-cones. Mouth-cone variable in shape, short or long, rounded or pointed; maxillary stylets more or less broad like those of idolothripine species, long, usually reaching eyes, usually parallel and touching together in the middle of head, but sometimes not reaching 8 S. OKAJIMA eyes and more or less apart from each other; maxillary bridge usually absent, sometimes present but weak and narrow. Praepectus absent. Epimeral suture usually complete. Foretarsi each with a tooth in both sexes. Metathoracic sternopleural sutures present. Metanotal median pair of setae usually weak. Fore- wings not constricted medially; with DC. Pelta bell-shaped or rather triangular, a pair of micro-pores present or absent. S4 to S7 of male usually with transverse reticulated areas. Tube usually shorter than head, sometimes longer, variable in shape. ComMENTS. Nine genera were synonymized with this genus by Mound & Palmer (1983: 92-93). The present author has re-examined most of these synonymized genera, and agrees with this treatment of them, except for the genus Panceratothrips Bagnall (see above). Abiastothrips was erected originally as a subgenus of Trichothrips for a species, schaubergeri, with the head almost as long as broad, and with the inter-antennal projection exceptionally broad. However, one of the subsequent members, soror, has a more slender head which is intermediate between schaubergeri and Holothrips species. Moreover, one Australian species of Holothrips, australis, has a somewhat broad inter-antennal projection. Pseudosymphothrips was also erected for a single species, yuasai, and cannot be distinguished satisfactorily from Holothrips by the general appearance. The genus Holothrips includes a wide range of shapes of the head, maxillary stylets and tube. The head is usually short and weakly or not elevated medially, but sometimes elongate and strongly elevated. The maxillary stylets are usually curved simply or rather straight in the mouth-cone, but sometimes looped or angulate laterally. Moreover, the range appears as a morpho-cline, more or less continuous and cannot be divided into subgroups. The genus Docessissophothrips, which is most clearly related to Holothrips, has been distinguished by the head long and strongly elevated medially and the maxillary stylets looped or angulate laterally. These features appear to be shared with some Holothrips species and are insufficient to distinguish the two genera, and Holothrips could therefore well be treated as a synonym of Docessis- sophothrips. Unfortunately the unique holotype male of ampliceps, the type-species of Docessis- sophothrips, is in a more or less poor condition, having been remounted into balsam from dry material on a card, therefore the present author cannot compare these two genera closely. Key to the Old World species Three species, angulatus, stannardi and titschacki, have not been studied by the present author and are excluded from this key. One Hawaiian species, sakimurai, newly described below is included with the Old World species. The type-locality, not the full distribution, is given in parentheses. 1 Tube shorter than 2-0 times as long as basal width; dorsal surface of head generally covered with transverse rows of weak and fine striation or reticulation (Figs 9, 11,13) ..................... 2 — Tube longer than 2-1 times as long as basal width, if shorter than 2-0 times, dorsal surface of head withidistinct polysonalireticnlatton)::s.5c-cceqseee-eseee ee ee ee eee eee eee nee ee eee 4 2 Head much longer than 1-5 times as long as broad; ocellar region distinctly convex (Fig. 9); all tibiae dark brown (Brunel): . e.aereu dc onena hates nacneane nee eeeeeeee brevicollis sp. n.(p. 19) — Head shorter than 1-5 times as long as broad; ocellar region not distinctly convexed; mid and hind tibiae langely yellow, so .ccsjc tae vaccine dose sete see eGat ace mene aeeec ec tere- Oaceee toe aR ee EEE eee 3 3. Maxillary stylets angulate in mouth-cone (Fig. 11); well-sclerotized robust species (Sulawesi) parallelus sp. n.(p. 39) — Maxillary stylets not angulate in mouth-cone (Fig. 13); weakly sclerotized feeble species (Philippines: azOm)e-. 2h ecantee aceon esas. Aon cra eae cece ade ae cere brevitubus sp. n.(p. 20) 4 Mouth-cone short and rounded, at least not sharply pointed ..................ceccceeceeeeeeeeneeeeeeeees 5 = Mouth-conelong andipomtedis ¢ y-esnase-oseetetes oe eee eee eee eee cose en eects eae ee eee eee 43 5 Mid-vertex (mid-dorsal) head setae, also B1 and B2 setae on T9 expanded at apex (South ATTICA) coco oat npetennich hestacecee Gan amee epee eee luteus (Faure) (p. 32) [cf. titschacki(Priesner) (p. 50)] — Mid-vertex head setae and B2 setae on T9 sharply pointed at apex, B1 on T9 variable in shape, poimted, blunt, expanded or knobbedic5. cis. scat pose eeetesaccas see cre eek cee nee eee cae eee ee 6 6) Head muchilongenthan 1-Situmesiasilonpasi/brOadieeseee eee euch sate ote ee ee eee ee eee eee y = 7) Head'shorter thand-Sitimes:as longiasibroadlerem ees. eee- areca eee -ceee cece eer ee eee ee eee eee y) 7 Metathorax and apical fourth of tube yellow, the rest of body brown to dark brown; maxillary stylets angulate or looped laterally in mouth-cone (Fiji) .......... zimmermanni (Moulton) (p. 54) — Body uniformly dark brown; maxillary stylets smoothly curved or rather straight, not strongly AN GUL ALC cise ce cohnsd oc aedonuse veunise seambeneeentens rey cominaser ae ce csetalssee secines selsctae sameeren te cseee 8 Hindtibiae yellow; head 1-5—1-7 times as long as broad (Fig. 20) (India) mirandus(Ananthakrishnan) (p. 34) — Alltibiae dark brown; head 1-75—1-80 times as long as broad (Fig. 17) (Java) nigripessp.n.(p. 36) 16 17 18 19 STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS Mubedimostaslonaasiheddionlongen sais. -cptasaece so dus access decker news telpnnseoadteiostuseacbnadeaSenait CEE STE og Uo 65 BE pa ee OS ee ee eee Maxillary stylets almost touching together at median portion of head, without maxillary bridge, See OSE FIO ARE IIIS OF CYS 025 5 pone nck eamaivcesa cscs van odn% Wau cins dade ducnenvesntaedilds cudeaveuieats Maxillary stylets more or less apart from each other, with weakly developed maxillary bridge, not reaching posterior margins of eyes (Figs 29, 33,37, 39, 41,44) ..... 0... cee ceceecenee eee eeee Tube almost as long as head, with some longitudinal wrinkles (Fig. 23); A7 almost as long as A6 ora little shorter; cheeks almost straight, subparallel (Fig. 22) (Brunei)........ storkisp. n. (p. Tube slightly longer than head (Fig. 27); A7 longer than A6; head broadest across cheeks at Ree M NCA REMNENG BED) DOW cian ness htensands ands oaliextbadesenas«ub'easosigoshacennasarces torajanus sp. n. (p. Body largely yellow; antennae longer than 2-5 times as long as head; A3 longer than 3-0 times asiene as broad (Fie: 40) (Philippines: Luzon) .....3....-...cssesecsetevesseasnecsecs flavus sp. n. (p. Body brown to dark brown; antennae shorter than above ..................scceceeeeececeeceeeeeeeeeeenes Maxillary stylets not reaching level of POS (Fig. 44) (Philippines: Mindanao) maxillaesp. n.(p. PM emilan sive tSieaCDInPlEVEl OREO a,c. suere es encisnaaananees rine \ oo a >~ a O O 2 *, a haan Or sae a4 MA | Hy ‘Ne : ie \ | bed 2 ASN / ee Rey ed \\\ CH Ee |hi II\ ee a eee ts Y, elt 1/158 \ igen iees \ \ et S / \ \\ y ee RY ee ee eee / ss v4 i “7 NN \\ (/ “fi. “f SX / = \ . ae * a ‘at pa Figs 144-155 Holothrips species. 144, 145, H. soror Q: (144) head; (145) tube. 146, 147, H. schaubergeri Q: (146) head; (147) tube. 148-150, H. flavitubus 2: (148) head; (149) tube; (150) antennal segment (154) head; (155) tube. VII. 151-153, H. peltatus 9: (151) head; (152) tube; (153) antennal segment VII. 154, 155, H. subtilis 9: 70 S. OKAJIMA Figs 156-167 Holothrips species. 156, 157, H. flavicornis Q: (156) head; (157) tube. 158, 159, H. ananthakrishnani 9: (158) head; (159) tube. 160, 161, H. porifer 2: (160) head; (161) tube. 162, 163, H. cupreus Q: (162) head; (163) tube. 164, 165, H. castanicolor 9: (164) head; (165) tube. 166, 167, H. breviceps 2: (166) head; (167) tube. STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS 71 Figs 168-180 Holothrips species. 168-173, peltas: (168) H. flavitubus; (169) H. peltatus; (170) H. flavicornis; (171) H. porifer; (172) H. cupreus; (173) H. castanicolor. 174-177, H. falcatus 9: (174) head; (175) tube; (176) pelta; (177) antennal segment VII. 178-180, H. moundi 9: (178) head; (179) tube; (180) pelta. 92 S. OKAJIMA OPS ( 8 JY OR] OV 4 fA 474 cay / Figs 181-193 Holothrips species. 181-183, H. celebensis 2: (181) head; (182) tube; (183) apical portion of antennal segment III. 184-186, H. formosanus 9: (184) head; (185) tube; (186) antennal segment VII. 187, ?H. typicus CO’, forefemur. 188, 189, H. yuasai : (188) head; (189) tube. 190, 191, H. attenuatus Q ; (190) head; (191) tube. 192, 193, H. hagai 9: (192) head; (193) tube. STUDIES ON THE OLD WORLD SPECIES OF HOLOTHRIPS 73 199 200 201 EA AA Spar se CES Figs 194-207 Holothrips species. 194-198, peltas, (194) H. celebensis; (195) H. formosanus; (196) H. yuasai; (197) H. attenuatus; (198) H. hagai. 199-201, antennal segment VII: (199) H. hagai; (200) H. yuasai; (201) H. hasegawai. 202-204, H. fumidus 2: (202) head; (203) tube; (204) pelta. 205-207, H. hasegawai 9: (205) head; (206) tube; (207) pelta. 74 Synonyms are in italics Abiastothrips 7 Adelothrips 7 africanus 12 Agnostothrips 7 ananthakrishnani 13 andamanensis 14 andrei 14 angulatus 14 angulus 15 antennalis 15 apoensis 16 armatus 17 associatus 30 attenuatus 17 australis 18 breviceps 18 brevicollis 19 brevitubus 20 castanicolor 20 caudatus 21 celebensis 21 cephalicus 22 citricornis 23 Cordylothrips 7 cracens 23 cupreus 23 curvidens 24 debilis 50 Erythrinothrips 7 falcatus 25 flavicornis 25 flavitubus 26 S. OKAJIMA Index flavus 27 formosanus 27 fumidus 28 hagai 29 hasegawai 30 Holmiella7 Holothrips 7 indicus 30 Ischnothrips 7 japonicus 31 kuntiae 31 Lathrobiothrips 7 latidentis 32 lativerticis 46 luteus 32 luminosus 33 maxillae 33 mirandus 34 moundi 35 nepalensis 35 nigripes 36 nigritus 37 oceanicus 37 ogasawarensis 37 okinawanus 38 Panceratothrips 7 parallelus 39 peltatus 40 peninsulae 40 pictus 41 porifer 42 priesneri 46 Pseudosymphothrips 7 pulchellus 43 quadrisetis 43 ruidus 44 ryukyuensis 44 sakimurai 45 sawadai 46 schaubergeri 46 semiflavus 47 setosus 47 soror 48 speciossissimus 48 stannardi 49 Stinothrips 7 storki 49 subtilis 49 tibialis 50 titschacki 50 torajanus 51 torosus 51 typicus Holothrips 52 typicus Panceratothrips 7 unicolor 52 yuasai 53 yurikoae 53 zimmermanni 54 Titles to be published in Volume 54 Studies on the Old World species of Holothrips (Thysanoptera: Phlaeothripidae) By S. Okajima Spectacles and Silver Ys: a synthesis of the systematics, cladistics and biology of the Plusiinae (Lepidoptera: Noctuidae) By I. J. Kitching A review of the Solenopsis genus-group and revision of Afrotropical Monomorium Mayr (Hymenoptera: Formicidae) By B. Bolton Photoset by Rowland Phototypesetting Ltd, Bury St Edmunds, Suffolk Printed in Great Britain by Henry Ling Ltd, Dorchester