Seal ui ay ! ee Va Pt Dib y Weta ge ue LB ie eeuteel Fete nacido v a PA A i Web tisk yay Aa A paas| oA aa ied pig be hOb Fe Pia ih ‘ BAY NC i Ae ad ( Oat } y ibe oa! ; x i TARA ‘ ‘ 1 oe at a vy 6 a8 Win LIBRARY OF THE UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN NOTICE: Return or renew all Library Materials! The Minimum Fee for ©ach Lost Book is $50.00. L161] —O-1096 Digitized by the Internet Archive in 2011 with funding from University of Illinois Urbana-Champaign http://www.archive.org/details/classificationev45ross —_—- — 7 5 ae i i a , = = oe ILLINOIS BIOLOGICAL. MONOGRAPHS ILLINOIS BIOLOGICAL MONOGRAPHS Volumes 1 through 24 contained four issues each and were available through subscription. Beginning with number 25 (issued in 1957), each publication is numbered consecutively. No subscriptions are available, but standing orders are accepted for forthcoming numbers. 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RICKER ILLINOIS BIOLOGICAL MONOGRAPHS 45 UNIVERSITY OF ILLINOIS PRESS URBANA, CHICAGO, AND LONDON Board of Editors: Donald F. Hoffmeister, Willard W. Payne, Tom L. Phillips, Richard B. Selander, and Philip W. Smith. This monograph is a contribution from the lilinois Natural History Survey. Issued Augusi 1971. © 1971 by The Board of Trustees of the University of Illinois. Manufactured in the United States of America. Library of Congress Catalog Card No. 74-135472. 252 00140 O CONTENTS INTRODUCTION PHYLOGENETIC POSITION OF ALLOCAPNIA SYSTEMATIC TREATMENT OF ALLOCAPNIA Genus Allocapnia Diagnosis Terminology Distribution Records Material Studied Use of the Keys to Species Key to Sexes Key to Males Key to Females Species Accounts The vivipara Group The recta Group The virginiana Group The granulata Group The mystica Group The dlinoensis Group The forbesi Group The jeanae Group The rickeri Group The pygmaea Group PHYLOGENY Ancestral Character Conditions — OoOMmMMOmoOnNnNN Ww Evolution of the Species Groups The vivipara Group The recta Group The granulataGroup The mystica Group The illinoensis Group The forbesi Group The jeanae Group The rickeri Group The pygmaea Group GEOGRAPHIC DISPERSAL Vagility Association with Pleistocene Events Dispersal Patterns of Species Groups The vivipara Group The recta Group The virginiana Group The granulata Group The mystica Group The ilinoensis Group The forbesi Group Tachytely in minima The jeanae Group The rickeri Group The pygmaea Group Early Ancestral Types DISPERSALS AND TIME Comparative Ecology Midwestern Flatlands Mississippi Embayment The Illinois Ozarks Corridor The Northeastern Gateway Allocapnia Dispersal Patterns Time Correlations Early History of Allocapnia Transatlantic Dispersals The Appalachian-Ozark Corridor Later Dispersals Glacial Stages and Speciation Post-Woodfordian Dispersals Evolution of Local Endemics SUMMARY ACKNOWLEDGMENTS LITERATURE CITED FIGURES INDEX INTRODUCTION The study reported here had a most unpretentious beginning. During an informal discussion with colleagues in 1956 the question arose: which insect groups have distribution patterns that might contribute reliable information concerning the effect of the Pleistocene glaciers on the biota of eastern North America? Early in the discussion it became clear that highly vagile insects such as winged grasshoppers and leafhoppers disperse so rapidly that their present distribution is largely an expression of ecological rather than historic factors. Certain wingless insects, such as Collembola, have remarkably wide ranges but are easily transported by air currents and are therefore not valid as expressions of historic dispersals within a limited area. At this point the idea of the cold climates associated with Pleistocene glaciers became associated in our minds with the cold-tolerant stone- flies. A rapid check on some of their distributions as known at that time turned up a most interesting item: the winter stonefly Allocapnia pygmaea was primarily a subboreal species in northeastern and eastern North America, but it had an isolated population in the Ozark Moun- tain area of Missouri. The Missouri population appeared to be a segment of a cold-adapted species left stranded to the south when the remainder of the species moved northward in postglacial times. 2 WINTER STONEFLY GENUS Allocapnia Our interest caught by this circumstance, we decided to study the winter stoneflies with special reference to Pleistocene events. The winter stoneflies belong to a physiologically peculiar group of organisms. With the approach of winter, many living things are nor- mally thought of as becoming quiescent or dormant. In the temperate regions, leaves fall from the trees, the crops are harvested, the sound of erickets declines, and flowers with their attendant multitude of insects disappear from the landscape. For a few insects, however, winter heralds not a cessation but an acceleration of activity. A few erane flies, scorpion flies, caddisflies, and springtails complete their metamorphosis during the cold months of the year and may be found on the snow, on moss beds, or stream banks, where their activity contrasts strikingly with the quiet repose of the great bulk of the insect fauna hibernating in the vicinity. Among the most abundant of the active winter insects in temperate North America are the winter stoneflies, comprising representatives of several genera belonging to the families Taeniopterygidae, Nemouri- dae, Leuctridae, and Capniidae, all belonging to the same phylogenetic branch of the insect order Plecoptera (Ricker, 1950; Iles, 1960, 1965). The genus Allocapnia (Figs. 1-3) of the family Capniidae appeared to offer unusually good possibilities for biogeographic interpretation especially with regard to obtaining a better understanding of the evolution of the aquatic fauna of the temperate deciduous forest occurring in the eastern United States and Canada. Before these pos- sibilities could be explored further, it was necessary to re-examine the species composition, phylogeny, and systematic position of Allocapnia and its immediate relatives, and attempt to determine the total range of each species. To achieve the last objective, we enlisted the aid of many people in an effort to collect material from the entire eastern part of North America. Over 200 people responded to our request for help. Together they form a group that we call the “Winter Stonefly Club.” Most of them, like ourselves, enjoy getting out for a little brisk collecting when the desk chairs in the office begin to harden in January, February, and March. The full list of these collaborators is given in the acknowledgments. PHYLOGENETIC POSITION OF ALLOCAPNIA The genus being considered here was first described by Claassen (1924) under the name Capnella, a name that proved to be preoccupied and for which Claassen later (1928) substituted the new name Allo- capnia. Until recent years the genus has been considered distinctive, confined to eastern North America, and a close relative of the world- wide genus Capnia. There is some question whether it has affinities with the Japanese genus Takagripopteryx Okomoto, but we and most authors are of Hanson’s (1946) opinion that Allocapnia and Takagri- popteryx are different genera. In an effort to arrive at a better under- standing of this problem, we attempted to reconstruct the phylogeny of the Capniidae at least so far as it concerns the North American fauna. In this study we relied heavily on the morphological studies of Hanson (1946). Unfortunately, we were unable to obtain material of the Old World genera that were also unavailable to him, including species placed in Takagripopteryx. In this sense the family tree we propose is incomplete, but this should not reflect on its validity as a logical hypothetical beginning. In comparing various genera of the Capniidae with those of the Taeniopterygidae, Nemouridae, and Leuctridae, it is highly probable that the ancestral Capniidae possessed, among others, the following primitive characters: hind wing with veins R, and R;; metafurcaster- 3 + WINTER STONEFLY GENUS Allocapnia num rectangular and the same size as mesofureasternum; postfurca- sternal plates (pfs) separate; vesicle (ventral lobe) present at the anterior margin of the ninth sternite (98); at least one crossvein present in the costal space; A, of fore wing not sharply bent near the Cu-a crossvein; epiproct (supra-anal process) of the male a single structure, undivided. No living genus of stoneflies is known with this combination of characters. The genus Isocapnia has primitive venation and meta- fureasternum but has the postfurcasternal plates fused. All the other genera lack veins R; and R; in the hind wing. From this it seems that the ancestral Capniidae possessed both characters in the ancestral condition and gave rise to two branches, one leading to Jsocapnia in which only the postfureasternal plates became changed, and another leading to Ancestor 1 in which the hind wings lost veins R; and R; (Fig. 4). Ancestor 1 is represented by a persisting branch, the genus Paracapnia, that, except for loss of the vesicle, appears to be little changed. In addition it apparently gave rise to Ancestor 2, in which the metafureasternum became reduced. Ancestor 2 apparently gave rise to three lineages: (1) a line exhibiting little change, represented by the genus Eucapnopsis; (2) one in which the postfurcasternal plates became fused and the vesicle and the costal crossvein were lost, repre- sented by the two closely related genera Capnioneura and Nemocapnia; and (3) a lineage in which the mesofurcasternum became triangular and vein A, became bent in the fore wing, evolving into Ancestor 3. Ancestor 3 gave rise to three lineages, two little changed and repre- sented by the hingstoni and gregsoni groups of Capnia, and a third in which the ventral lobe of the male 9S was lost, resulting in Ancestor 4, represented by some Capnia and Allocapnia. The Old World and New World species known to us that apparently arose from Ancestor 4 can be arranged in 10 species groups assigned to the genus Capnia plus the genus Allocapnia, as indicated in Fig. 4. Of the species groups assigned to Capnia, the bifrons, oenone, and melia groups have no dorsal process on the male seventh and eighth tergites; the remainder have a dorsal process on the male seventh tergite and appear to represent Ancestor 5 in which this structure appeared. In the excavata, atra, nigra, and elongata groups the epi- proct is simple or nearly so, the ancestral condition for the family. In the manitoba, columbiana, and vidua groups the epiproct is deeply divided, indicating that all three arose from a common progenitor (Ancestor 6) possessing this character. Ancestor 6 gave rise to two lineages. In one, leading to Ancestor 7 (parental to the manitoba and columbiana groups), the epiproct is V- or U-shaped in profile (Fig. 5). PHYLOGENETIC POSITION OF Allocapnia 5 In the other lineage, leading to Ancestor 8, the epiproct is composed of dorsal and ventral limbs closely appressed and forming a single func- tional unit. Ancestor 8 gave rise to the vidua group and to Allocapnia. In both the vidua group (Fig. 6) and Allocapnia, the dorsal limb of the epiproct has a sharp bend or elbow some distance from the apex; at the apex there is a membranous area surrounding the gonopore, through which the eversible aedeagus is extruded; and the lower limb of the epiproct has a curious apical portion set off by a marked con- striction from the long base. The two parts are rigidly joined at the base as a stout curved structure. By force, the two parts may be separated without breaking to an angle of 20 or 30 degrees; when the force is released, the spring tension of the basal loop causes the two parts to snap back together again. It seems highly unlikely that such a complex mating structure would have evolved twice and, on this basis, the only reasonable assumption is that Allocapnia arose from a form very much like a primitive member of the vidua group. In the manitoba, columbiana, and vidua groups the male seventh tergite has a dorsal process but not the eighth; in Allocapnia the male eighth tergite always has a dorsal process and in all primitive species of the genus the seventh has none. It is evident that in Allocapnia the pri- mary dorsal process has moved from the seventh to the eighth segment, as has apparently happened also in some lineages of Capnaa. In the groups of Capnia having a simple epiproct (hingstoni group to elongata group in Fig. 4), the base of the ninth tergite has only a thin sclerous thickening along its lateral and dorsal margins (Fig. 7) ; in the manitoba and columbiana groups this basal thickening 1s slightly to moderately strengthened in the mesal region (Figs. 8, 9); in the vidua group the lateral portions of the basal thickening are wide, but the mesal part is absent and this portion of the dorsal margin is membranous (Fig. 10); in Allocapnia the basal thickening has wide lateral portions and a strong U-shaped sclerous mesal portion (Fig. 11). These structures also support the close affinity of the vidwa group and Allocapnia. It is a simple matter to construct a common ancestral form (Ancestor 8) roughly intermediate between the two and explain the existing structures by postulating an atrophy of the mesal portion in vidua and a strengthening and accentuation of this portion in Allocapnia. The chief morphological characteristic setting off Allocapnia from Capnia is the loss of the sutures of the praescuta on both the meso- and metathorax, together with an associated irregularity of wing venation. Both of these changes are apparently associated with greatly reduced flight potential in Allocapnia. The loss of the prae- 6 WINTER STONEFLY GENUS Allocapnia scutal sutures is probably associated with the atrophy of muscles in- volving flight, and the irregularities of venations are probably due to a reduction of selection pressures that would normally maintain the areodynamic pattern of fully functional wings. Despite its phylogenetic position as a branch of Capnia, we believe that Allocapnia should be designated as a separate genus because of the many distinctive features that have evolved. This designation of Allo- capnia as a separate genus without treating other branches of Capnia in like manner is an example of paraphyletic classification, strongly criticized by some (Hennig, 1966). There are, however, many well- known examples of it in classification; for example, the recognition of Mammalia, Aves, and Reptilia as separate classes. There is no doubt that paraphyletic classification is a convenience that will con- tinue to have frequent use. SYSTEMATIC TREATMENT OF ALLOCAPNIA GENUS ALLOCAPNIA CLAASSEN Capnella Claassen (1924:43). Type-species Capnella granulata Claas- sen. Name preoccupied. Allocapnia Claassen (1928:667). New name. Diagnosis. In general features, Allocapnia is typical of the family Capniidae. It differs from allied genera in that the meso- and meta- notum lack praescutal sutures. It differs from all other known members of the family, except Capnia vidua, in possessing a double epiproct of distinctive complex structure and from that species it differs in having a dorsal process on the eighth sternite of the male and in the pattern of sclerotization of the male ninth segment (Fig. 11). Unless otherwise noted in the species accounts, the 38 known species are uniform in shape, size, and color, as follows: length from tip of head to end of abdomen about 5 mm in the male and 6 mm in the female; color dark brown, the wings slightly smoky with brown veins; in the females the wings extend beyond the tip of the abdomen (Fig. 1); in the males the wings vary greatly in length within and among the species (Figs. 2, 3). Known diagnostic characters separating the species occur chiefly in the genital characters associated with the seventh and more posterior segments of the males, and in the seventh ‘ 8 WINTER STONEFLY GENUS Allocapnia and eighth sternites of the females. To date, reliable diagnostic charac- ters for the nymphs are unknown. Frison (1929, 1935) published considerable biological information concerning members of the genus. All known species of the genus except minima are restricted to the temperate deciduous forest of eastern North America and its ecotone areas with the coniferous forest immediately to the north. The excep- tional species minima occurs in Quebec almost to the northern limit of trees. The adult emergence of the species is tied closely to the winter season. In the southern states adults emerge from November into January; at the latitude of Illinois, from late November into March; and in southern Canada, principally in March and April with no evidence of an earlier fall emergence. This winter emergence is by no means a unique feature of Allocapnia; many other genera of stoneflies share it. Terminology. Names used in this paper for morphological structures are those employed by Hanson (1946). Parts of the genitalia or asso- ciated structures commonly used are indicated in Fig. 12 (male parts) and Fig. 51 (female parts). Distribution records. For all species the distribution records have been plotted on maps. If we have 10 or less localities from which a species is known, we have cited the complete collection data available. If we have more than 10 records, we have summarized the dates and ecological notes and listed the states and provinces of occurrence. In total we have records from about 3,000 localities (Fig. 87), but many of these are only a few miles apart and impossible to show on a small- scale map. Upon request, a detailed list of records is available from the Illinois Natural History Survey. Material studied. Material available for study includes the extensive winter stonefly collections assembled by the late T. H. Frison and large recent accessions gathered by the Winter Stonefly Club and our colleagues in the Section of Faunistic Surveys and Insect Identification of the Illinois Natural History Survey. The entire winter stonefly material assembled from eastern North America totals about 250,000 specimens, of which about 150,000 belong to the genus Allocapnia. Aside from type-specimens, whose depositories are stated specifically, the majority of this material is in the collection of the Illinois Natural History Survey. The remainder has been returned to the Canadian National Insect Collection, Cornell University, The United States National Museum, and the collections of Dr. S. W. Hitchcock, New Haven, Connecticut, and Dr. P. H. Freytag, Lexington, Kentucky. SYSTEMATIC TREATMENT OF Allocapnia 9 Voucher specimens of all but the rarest species have been deposited in the following collections: Academy of Natural Sciences, Philadelphia, Pennsylvania American Museum of Natural History, New York, New York Auburn University, Auburn, Alabama British Museum (Natural History), London, England California Academy of Sciences, San Francisco, California Canadian National Insect Collection, Ottawa, Ontario, Canada Cornell University, Ithaca, New York Field Museum of Natural History, Chicago, Illinois Florida Department of Agriculture, Gainesville, Florida Ohio State University, Columbus, Ohio Oregon State University, Corvallis, Oregon Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts North Carolina Department of Agriculture, Raleigh, North Carolina Purdue University, West Lafayette, Indiana University of Georgia, Athens, Georgia University of Kansas, Lawrence, Kansas University of Michigan, Ann Arbor, Michigan Use of the Keys to Species Characters used in the following keys to the males and females are based on the visibility of diagnostic structures as seen in well-extended specimens or specimens sufficiently pliable that the structures and segments to be seen can be manipulated into a satisfactory orientation. Shrunken specimens cannot be keyed satisfactorily. In the case of the males, satisfactory preparations can be obtained by macerating the abdomen in potassium hydroxide solution, sufficiently to dissolve the viscera to the point that they can be worked out of the specimen, but not enough to cause any drastic loss of color in the integumental structures. Bleaching of very dark specimens to a lighter shade can be accomplished by judicious use of a solution of hydrogen peroxide and ammonium hydroxide. Cleared specimens are best seen as free prep- arations in glycerine. Structures of the female are best seen on a well-extended, uncleared specimen. If the specimen is shrunken and difficult to manipulate, the abdomen can be macerated slightly with a potassium hydroxide solu- tion and a fairly satisfactory preparation obtained. 10 WINTER STONEFLY GENUS Allocapnia KEY TO SEXES Dorsum of terminal segments with a complex of structures including a forked sclerous epiproct and a dorsal scle- rous projection on at least the eighth tergite (Fig. 12) Dorsum of abdomen without any processes; eighth sternite modified into a simple subgenital plate of various shapes. (Wier. 51-83) 2. as. e.oxs ise ea tanews females KEY TO MALES 1 Apical segment of upper limb of epiproct longer than basal segment and massive; eighth tergite with a large, flat, cushionlike process and a small anterior process Cig 0) 2s owes. edocs hat cane virginiana = (p. 25) Apical segment of upper limb of epiproct either much shorter than basal segment (Figs. 38, 43) or not nearly so massive (Figs. 23, 24); eighth tergite either lacking anterior process or with posterior process not forming a larce cushion (Pies, 21-49). oc news. ce See sewe ees 2 a(t) Upper limb of epiproct extremely thin, curved up and pointed at tip; process of eighth tergite small and bittonlike (Wiei 19) ccus.s4 Ge adtindddes loshada_ (pp. 25) Upper limb of epiproct either much thicker, or straight, or depressed at tip (Figs. 15-18); process of eighth tergite either buttonlike: or otherwise. WINTER STONEFLY GENUS Allocapnia MISSISSIPPI EMBAYMENT The Coastal Plain of the southern and eastern United States is almost devoid of Allocapnia. The only known exceptions are certain hilly areas having spring-fed streams, including the Jackson Dome area and the area north of it in Mississippi; the Monroe Uplift and associated hill country of southern Arkansas, northern Louisiana, and nearby Texas; and the Conecuh County cave area in southern Ala- bama. In these exceptional areas are found recta, malverna, and gran- ulata. Otherwise the Coastal Plain appears to have acted as a rigid barrier for occupaney by Allocapnia. The Mississippi Embayment, simply a north-central lobe of the Coastal Plain, shares this barrierlike characteristic except for a few peripheral records of granulata and vivipara. It is evident from the ranges of various Allocapnia species that there is no free traffic of clear-stream species across this area. A comparison of the ranges of mohri (Fig. 89) and recta (Fig. 90) demonstrates the point decisively. THE ILLINOIS OZARKS CORRIDOR The area called the Illinois Ozarks is a small unglaciated band of hills with a maximum elevation of about 1,000 feet extending across the southern end of Illinois. The area has numerous, clear spring-fed streams in rocky defiles and in these several Allocapnia abound. This hill country is separated by only the Mississippi River valley from similar hill country in Missouri and by only the Ohio River valley from hill country in Kentucky that is lower in elevation but neverthe- less rich in artesian streams. The northern flatland area extends to the base of the hills on the northern side of the Illinois Ozarks and the Mississippi Embayment extends slightly north of the Ohio River in Illinois to their southern flank. The Illinois Ozarks thus constitute a unique corridor of suitable Allocapnia habitats connecting the Cumberland Plateau-Appalachian area with the Ozark-Ouachita area of Missouri and southwestward. In the few small-stream Allocapnia species occurring in both areas, this circumstance has produced ranges shaped like an hourglass (mystica, Fig. 96; rickeri, Fig. 102). THE NORTHEASTERN GATEWAY Because of the east-west position of the flatlands, the northern end of the Cumberland Plateau and the Appalachians form a corridor of varied Allocapnia streams connecting extensive northern and southern areas inhabited by Allocapnia. DISPERSALS AND TIME 77 Allecapnia Dispersal Patterns In attempting to adduce dispersal patterns in Allocapnia, one soon realizes that these patterns fall into two sharply defined categories. First are the instances in which a species occurs in a previously gla- ciated area; here it is obvious that the stonefly must have dispersed into the area since the last deglaciation. Second are the instances in which either the species does not now occur in a formerly glaciated area but for which there is evidence indicating a past range change, or that an ancestral form dispersed between two areas. In the first group both the approximate time and direction of dispersal are ob- vious — after the last major deglaciation and northward. In the sec- ond group neither time nor direction is immediately obvious. In order to bring both categories into a cohesive general pattern, some means must be found to equate as well as is possible the circum- stances of one category with those of the other. At this moment of writing the only equating factor is the amount of morphological dif- ference between various contrasting species or sets of species. Such an equating is in reality one of the most dangerous attempts in phy- logeny, that is, equating amount of change with duration of time. A high degree of probability is evident in Simpson’s (1944) demonstra- tion that rate of change normally varied modally within evolving lineages of a group, but that it might reach unexpectedly higher or lower values in a relatively small proportion of abnormally evolving lineages. On this basis, such correlations give as good an indication of the true course of events as is possible without additional data. Hypotheses advanced on such reasoning form a logical preliminary basis for summarizing present information. By means of this time-change correlation, the Allocapnia dispersals outlined in the preceding section may be categorized into the following classes: 1. Ranges now found well into previously glaciated areas. Pre- sumably post-Woodfordian (the last extensive glaciation of the Wis- consinan Ice Age). Examples include minima (Fig. 100), nivicola (Fig. 109), and zola (Fig. 103). 2. Extensive east-west ranges in which there is little or no variation between geographic extremes. Included are vivipara (Fig. 88), mystica (Fig. 96), and rickeri (Fig. 102). These ranges imply dispersals that probably occurred contemporaneously with those of Class 1. 3. Extensive north-south ranges along the axis of the eastern moun- tain chains in which there is little interpopulation variation. Included id 78 WINTER STONEFLY GENUS Allocapnia are virginiana (Fig. 92), loshada (Fig. 89), and aurora (Fig. 105). These ranges also probably involved local dispersals that occurred simultaneously with those of 1 and 2. 4. Ranges having pronounced disjunctions in which the disjunct populations differ slightly. Included are pygmaea (Fig. 104) and ill- noensis (Fig. 97). These disjunctions probably involved ancestral forms of the same age as the glacial maximum parents of Classes 1-3. 5. Ranges having disjunctions in which the disjunct populations differ sharply in one or more morphological characters. Included are recta (Figs. 90, 91) and granulata (Figs. 94, 95). The dispersing an- cestral forms of these species presumably occurred before those of Classes 1-4. 6. Distinct sister species occurring in different regional areas, such that an ancestral widespread species must have become disjunct. Ex- amples are the frisoni-peltoides pair, arising from Ancestor 25; the unzickeri-warreni pair, arising from Ancestor 24; and the ozarkana- forbesi pair, arising from Ancestor 26. The ancestors of these pairs of species must have dispersed prior to those of Class 5. 7. Ancestral forms occurring earlier in the family tree than those in Class 6, and necessarily representing widespread species that later became restricted and split into two or more offspring lineages. In this class are Ancestors 20, 15, and 27. On morphological grounds, the dispersals of these ancestors should have preceded those of Class 6. 8. Not included in the above categories except as implied phyloge- netic informants are several species that have small ranges (indianae, Fig. 107; ohioensis, Fig. 106; and cuwriosa, Fig. 98), and 14 species that classify as local endemies (e.g., brooksi, Fig. 88; polemistis, Fig. 89). It is possible to fit these into some sort of dispersal scheme only as this is developed for better-known species of the genus. Time Correlations Only a decade ago it might have seemed logical to fit the preceding dispersal classes into a simple rational correlation with the then- understood pattern of late Pleistocene events (Rosholt et al., 1961). This was suggested by H. H. Ross (1965) for certain Allocapnia species. This earlier pattern presupposed an extensive Wisconsinan glaciation having a relatively uniform cold temperature at least as far south as central or southern Illinois. More recent geologic researches (Frye et al., 1968, 1969; Willman and Frye, 1969) have established DISPERSALS AND TIME 79 that earlier concepts of midwestern Pleistocene events were an over- simplification of a much more complex glacial history. In the Midwest and presumably also in eastern North America gen- erally, Frye and his colleagues have unearthed evidence that the Wis- consinan had at least three successive warmer pulses alternating with three cold pulses, not including the shorter Valderan cold pulse of 11,000 years ago (Fig. 110). Previously this epoch had been consid- ered as only a single cold pulse. In the light of these new discoveries it is necessary to re-examine completely all previous ideas concerning Allocapnia Pleistocene dispersals. EARLY HISTORY OF ALLOCAPNIA The family Capniidae is primarily a boreal to subboreal group of stoneflies widely distributed across North America and Eurasia. From Fig. 4 it is seen that there have been many past dispersals of capniids between the two continents, including Ancestor 8, the parent of Allo- capnia and its sister branch, the vidwa group of Capnia. Going back further down the tree in Fig. 4, it is logical to conclude that Ancestor 5 was intercontinental and later its range was divided into two or more: the Eurasian and North American isolates. This probably occurred sometime in Pliocene or earlier when the temperate deciduous forest was fragmented in similar fashion. One North American isolate evolved into Ancestor 6, which subsequently gave rise to Ancestor 7 and the manitoba-columbiana lineage of Capnia and to Ancestor 8. Ancestor 7 was probably originally in western North America, An- cestor 8 in eastern North America. Ancestor 8 in turn dispersed from North America to Eurasia. The high probability that Ancestor 7 was western, coupled with the rigid restriction of Allocapnia to eastern North American and the implica- tion that its Ancestor 8 was also originally eastern, leads to the con- clusion that Ancestor 8 dispersed from eastern North America to western Europe, following a course around the northern end of the Atlantic. The ecological correlation of Allocapnia with the temperate decid- uous forest supports the surmises concerning the possible Phocene age of Ancestors 5, 6, and 8 of Fig. 4. Allocapnia would thus be a relatively young daughter genus arising from a branch of the older genus Capnia. TRANSATLANTIC DISPERSALS In recent years, most investigators have assumed that Cenozoic dis- persals between Eurasia and North America occurred by way of the wm 0 WINTER STONEFLY GENUS Allocapnia Bering Bridge, from eastern Asia to western North America and vice versa. But gradually a surprisingly long list of instances has accu- mulated in which a transatlantic route appears more feasible. In addi- tion to the vidua group cited above, several examples occur in the Trichoptera or caddisflies (Ross 1956). The Rhyacophila stigmatica group occurs only in Europe; its sister Rhyacophila glaberrima group occurs only in eastern North America. In the genus Agapetus, the celatus group occurs only in North America, the related fuscipes and comatus groups only in Europe. Additional examples occur in other eroups of insects. It now seems indicated that a considerable traffic of north temperate organisms o¢curred between eastern North America and Europe more or less contemporaneously with the spread of capniid Ancestor 8. These dispersals were probably at a period when the land areas of the North Atlantie were either still contiguous or closer together than at present (Dietz and Holden, 1970), and when temperate climates were more northerly than now. THE APPALACHIAN-OZARK CORRIDOR According to C. A. Ross (1963, 1965), during early or middle Plio- cene when ancestral Allocapnia presumably evolved, the terrain be- tween the Appalachians and the Ozarks was a relatively gently sloping surface and probably had few if any streams in which the genus could have survived. During the Pliocene (the epoch before the Pleistocene) , considerable crustal uplift occurred, greatest along the Rocky Moun- tains and Appalachians and decreasing irregularly to the Mississippi Embayment and Gulf Coast areas. Local uplift occurred in the Ozark- Ouachita region and parts of the Cincinnati Arch. The elevation of the raised surfaces increased the gradient and promoted rapid erosion. The erosion produced many steep-sided valleys, breached the previous water table, and greatly increased the groundwater outflow in springs. These events produced the series of special aquatic habitats suitable for Allocapnia that form an almost continuous corridor from the Ap- palachians to the Ozarks. The Illinois Ozarks are the narrowest part of this development. Smaller areas southward in the Mississippi Embayment such as the Jackson Dome of Mississippi and the Monroe Uplift of southern Ar- kansas and northern Louisiana produced local areas having rocky, spring-fed streams, but these did not form a continuous southern corridor affording an Allocapnia dispersal route between the southern Appalachians and the Ouachitas. DISPERSALS AND TIME Sl It is almost certain that no Allocapnia species dispersed from the Appalachians to the Ozarks until the corridor of deep valleys and spring-fed streams had come into being. On this basis, Ancestor 3 of Fig. 86 might represent this first Appalachian-Ozarkian dispersal, and be considered late Pliocene in age. It is possible that the first Ozark colonist preceded Ancestor 3 and has become extinct, but of this we have no record. LATER DISPERSALS From the existence of Ancestor 3, with its possible dating of latest Pliocene or very early Pleistocene, there is a maximum of eight an- cestral forms (including Ancestor 3) from Ancestor 3 to the immediate ancestor of any existing species. The evolution of all the known species of the genus therefore requires a minimum of only eight periods in which Allocapnia species expanded their ranges and underwent range division that resulted in isolated portions separated from each other long enough to become species. The minimum number would be the actual number if ancestors at comparable levels of sequential speciation had indeed speciated at the same time. For example, if all speciations now represented by two species had come from ancestors that split up synchronously, then Ancestors 19, 22, 24, 25, 26, 30, and 34 would have existed and each split up at the same time. The amount of difference between the species in each pair is roughly comparable, lending support to the probability of ancestral synchrony. Similar circumstances are found at the next possible level of ancestral synchrony, involving Ancestors 2, 21, 28, 27, 29, and 33. In addition to a rough measure of morphological similarity, ecolog- ical comparisons add support to the idea of ancestral synchrony. Thirty-four of the 88 species of Allocapnia have the same general ecological requirements —a small, clear, rocky stream. The excep- tional four species are scattered through the family tree (vivipara, granulata, minima, and pygmaea in Fig. 86), indicating that each species evolved its different ecological characteristics independently from an ancestor having ecological requirements similar to most of the 34. From this conclusion there is a good hkelihood that all the numbered ancestors in Fig. 86 had nearly the same ecological toler- ances, and could be expected to have reacted synchronously to chang- ing environmental conditions. If we admit this evidence as substantial support for considerable synchrony of speciation in various lineages, we must still account for 82 WINTER STONEFLY GENUS Allocapnia nine successive periods, each conducive to speciation. Each period would need to provide (for Allocapnia) : 1. A cooler and presumably wetter period that would displace pop- ulations or allow them to disperse to new areas, and 2. A warmer and drier period that would cause breaks in the ex- panded ranges, the breaks continuing sufficiently long that the newly isolated populations evolved into distinct species. Functionally these circumstances are illustrated by several species. The populations of recta involving ancestral and derived forms in Alabama illustrate a circumstance in which the first step occurred but the duration of the isolation step was too short to allow time for the evolution of genetic and sexual isolation. As a result, the recta popu- lations of southern Alabama are a hybrid flock of the two morpholog- ical types (Figs. 90,91). Widespread granulata is a similar, but more complex, example of the same phenomenon (Figs. 94, 95). The two sister species ohioensis and indianae (Figs. 106, 107) illustrate an instance in which the second step was sufficiently long that the once- isolated populations became distinct species (Ross and Freytag, 1967). Glacial Stages and Speciation. There are three obvious possibilities to account for the nine or more speciation pulses needed to explain the phylogeny of Allocapnia since late Pliocene time: intraglacial specia- tion (occurring within a particular glacial stage), interglacial speci- ation (requiring a full glacial stage and its succeeding warm intergla- cial stage), or some combination of the two. Intraglacial speciation. Regarding Allocapnia, we have detailed morphological and geographic data that appear to indicate a correla- tion with certain intra-Wisconsinan events, but none that have any firm correlation with earlier intraglacial events. The discussion of intraglacial speciation is based therefore only on the Wisconsinan. A set of conditions that might account for Allocapnia speciation is the alternation of climatic pulses occurring within each glacial stage. Four of these are well documented for the Wisconsinan in both North America and Europe (Butzer, 1964; Frye et al., 1969), not counting Recent (Fig. 110). Each pulse is associated with a glacial advance of 8,000-10,000 years and a nonglaciated period of about the same length. Computed ocean paleotemperatures indicate that temperatures during the unglaciated periods were lower than those of today. Studies in Wisconsin by Black (1964, 1965) suggest that the climate there during the Farmdalian interglacial substage was considerably cooler than today. DISPERSALS AND TIME 83 If these calculations are correct, then we can make a reasonable reconstruction of the behavior of certain Allocapnia species during the Wisconsinan. The climates of the last 6,000 years are good examples of possibly the warmest interglacial periods within the Wisconsinan. If another glacier were to descend, with accompanying colder weather, the more northern extensions of widespread species that now extend into previously glaciated areas would disintegrate but populations to the south would probably be little affected. During the next warmer spell the same species would repopulate the deglaciated northern areas. There are virtually no present-day ranges that such an oscillation would break into new isolated segments for a long period of time. It is likely that such past intrastage oscillations produced the hybrid flock of ancestral and derived recta in southern Alabama (Fig. 91). If so, presumably only two of the four warm-cool pulses of the Wis- consinan affected these populations. Perhaps this apparently restricted oscillation of recta indicates that the differential climatic effect of intrastage pulses was almost completely suppressed at that distance from the glacial fronts. If the peregrinations of granulata occurred within the Wisconsinan, they would seem to be correlated with all four of the warm-cool pulses. The case of granulata is puzzling, because its western populations evolved modest morphological differences, whereas in equally wide- spread species such as mystica and rickeri no such phenomenon occurs. As suggested earlier, this discrepancy is easily explained if mystica and rickert occupied a relatively compact or small contiguous range throughout most of the Wisconsinan, then dispersed relatively rapidly in either later Wisconsinan or post-Wisconsinan. The intraspecific variation in recta and granulata supports the idea that, in Allocapnia, distinctive species did not evolve during the Wis- consinan but required longer periods of geographic isolation. Interglacial speciation. The conventional Pleistocene calendar (Fig. 111) accounts for only 314 long-term pulses (not including glacial oscillations within the Wisconsinan). If the Pleistocene had followed earlier glacial oscillations beginning in the Pliocene, we might attribute the needed 514 temperature pulses to pre-Pleistocene perturbations in the Pliocene. Beard (1969) presents evidence from deep-sea cores in the Gulf of Mexico that the Pleistocene began abruptly about 2.8 million K-Ar years ago, thus indicating that some other explanation is necessary to account for the early climatic pulses needed to explain the Allocapnia speciation pattern. Combined intraglacial-interglacial speciation. A possible answer S4 WINTER STONEFLY GENUS Allocapnia involves a point stressed by Frye et al. (1969) concerning Pleistocene investigations in general. They point out that as new study techniques have become available, at least with reference to terrestrial data, we have been able to detect greater detail of glacial and temperature oscillations in the geological record. It may very well be that the Illinoian, Kansan, and Nebraskan glacial stages (4, 3, and 5 times as long as the Wisconsinan, respectively) may each have consisted of two or more long-term pulses of cold and warm climates, pulses not detect- able by present analytic techniques. It is possible that most if not all the nine cold-warm pulses required to explain the Allocapnia speciation pattern did occur during the cal- culated 2.8 million years comprising the Pleistocene (Beard, 1969). This surmise does not rule out the possibility that some of the earlier Allocapnia speciations may have occurred during wet-dry cycles or as vet undetected cold-warm cycles of the 12 million years comprising the Pliocene. If most of the Allocapnia speciation pattern occurred during the Pleistocene, then many of the upper-level ancestors of Fig. 86, includ- ing Ancestors 19, 22, 24, 25, 26, 30, and 34, dispersed during the Ilh- noian glacial stage (Fig. 111). Their ranges were broken and the parts isolated during the Sangamonian interglacial stage. The resul- tant two species arising from each of Ancestors 22, 30, and 34 dis- persed and became sympatric during the Wisconsinan glacial stage (Figs. 108, 109). Carrying this account into the future, certainly the range of nivicola will be fragmented if the future climate of eastern North America is a hot one like that of the Sangamonian interglacial. POST-WOODFORDIAN DISPERSALS Up to this point we have made no mention of the possible effect on Allocapnia evolution of the climatic cycles that occurred after the last major and extensive ice advance, the Woodfordian substage (Fig. 110). Smith (1957) and others have demonstrated the use of postu- lated post-Woodfordian climates for interpreting the dispersal of ver- tebrates into previously glaciated terrain. The question arises as to whether these same events, encompassing the last 12,000 years, can shed light on either dispersals or other evolutionary developments of Allocapnia. There is a good possibility that the isolated population of nivicola in Wisconsin (Fig. 109) resulted from a dispersal via spring-fed streams from central Indiana, around the base of the Great Lakes, and northward into Wisconsin. Springs now devoid of Allocapnia and others on record but now destroyed could have been strategic stepping- DISPERSALS AND TIME (oa) Or stones along such a route. The dispersal of rickeri into its present northwestern outposts (Fig. 102) was undoubtedly post-Woodfordian, and may have occurred during a recent pluvial period in a stream-by- stream progression up the Mississippi Valley before man tampered seriously with the environment. In light of the marked morphological differences between different populations of recta and granulata, here thought to have evolved during the Wisconsinan, it is odd that the isolated Missouri population of pygmaea is so similar to the others. The disjunction producing this isolation was at first considered to date from early Wisconsinan (Ross et al., 1967). Now there is need to consider the possibility that pyg- maea dispersed from the East into its present northern range (Fig. 104) during the Farmdalian or Two-creekan substages and moved from Minnesota and Wisconsin into Missouri during the ensuing glacial substage. Concerning granulata, the last meeting of the eastern and western strains in eastern Missouri and western Illinois and possibly in Louisi- ana was undoubtedly during a pluvial part of post-Woodfordian time. The small amount of hybridization now in evidence indicates that the contact was either of short duration or involved only small numbers of individuals. EVOLUTION OF LOCAL ENDEMICS One circumstance indicating considerable pre-Wisconsinan evolution of Allocapnia concerns endemic species. Of the 38 species known, 14 classify as local endemics occurring considerably south of the maxi- mum glacial fronts: brooksi and tennessa (Fig. 88) polemistis (Fig. 89) fumosa, unzickeri, warreni, and peltoides (Fig. 93) zekia (Fig. 96) ozarkana (Fig. 98) jeanae (Fig. 101) cunninghami, perplexa, sandersoni, and stannardi (Fig. 103) In addition, mohri and loshada (Fig. 89) have relatively small ranges also well south of the maximum glacial fronts. None of these 16 species gives any indication of range movements in the immediate past. All but three seem to be restricted rigidly to artesian streams. The three exceptions are brooksi, fwmosa, and stannardi, restricted, or nearly so, to cascades in the Great Smoky Mountains, an unusual habitat from the standpoint of Allocapnia. 86 WINTER STONEFLY GENUS Allocapnia It appears that all 16 species have become so narrowly adapted to the locations where they occur as to be unable to disperse from them. This means that they are unable to survive in streams fed chiefly by surface run-off in those areas. It has been suggested that chemical composition of the water is the cause of this ecological restriction. It seems more reasonable to suppose that the cause of restriction is uni- formity of temperature throughout the entire year. Underground water usually issues at the mean annual temperature for the region, varies extremely little from winter to summer, and if the stream is undiluted the temperature effect carries a considerable distance down- stream. The deeper, narrower, and more heavily wooded is the valley, the greater is the distance of uniform temperature in the stream. Ecological specialization to the degree exhibited by these local en- demics seems to be explainable only by a lack of genetic plasticity concerning temperatures other than those in the occupied habitat. Interspecific competition might be invoked, but seems not to apply because the more widespread species occur abundantly in the same streams as do the local endemics. The simplest way to explain the situation is to suppose that each endemic originated from a widespread parent such as the present-day mystica or rickert (Figs. 96, 102) that spread to areas of artesian streams during a climatic period such as the present. Subsequently the climate became much warmer and/or drier, causing nonartesian streams to become markedly warmer in summer or to dry up in sea- sons of decreased rainfall. The range of the parent species would then be broken into isolated fragments, some situated in an artesian area. In each artesian area, any individuals dispersing out of the area would not reproduce. As a result, the population in each isolated segment would build up a genetic constitution adapting it only to the isolated area occupied by the population. The adaptive tolerance of the population would tend toward a much narrower spectrum than that possessed by the widespread ancestral form that was the original parent of the isolated population. In time, through negative selection, the entire colony would end up with an ecological tolerance only great enough to succeed in the world of restricted artesian temperatures. The longer the period of hot climates, the more dependent would be the isolated population on the artesian habitat. If the dependence were sufficiently great, when the climate became cooler or wetter, the sea- sonal temperature fluctuations inherent throughout the Allocapnia range would be a barrier to the dispersal of the artesian-adapted species. 0,2) a | DISPERSALS AND TIME The model best suited for such a series of adaptive changes in Allo- capnia would be a correlation with the hot interglacial stages (Fig. 111). Each of these would have provided warm surface streams in which Allocapnia could not survive, and would have lasted long enough to exert the above-postulated selection pressures for a period of at least 50,000 years. In this model, temperature and not decreased rainfall would have been the critical factor. The model requires an abundance of artesian water throughout the period, and this water originally comes from rain- fall in or within a few hundred miles of the occupied area. Presumably the rainfall was adequate to provide the necessary artesian flow. If these local endemics had dispersed and evolved during the sub- stages of the Wisconsinan (Fig. 110), there would need to have been temperature conditions during these mid-Wisconsinan substages as high as or higher than those occurring now. Evidence so far at hand indicates the opposite (Black, 1964, 1965). Also, if these endemics had been of intra-Wisconsin origin we should expect to find more isolated outposts of some of the species, as for zllinoensis (Fig. 97), or a larger number of closely related sister species. To make the model operable on a continuing basis, one more postu- late must be made. The local isolation and selection pressures de- scribed would seem to drive the evolution of the genus in the direction of an assemblage of local endemic species having no power to disperse again. Yet the genus now contains 17 species that have been able to disperse into previously glaciated regions, 10 of them extensively. Two circumstances appear to be involved. First, some lineages appear to have maintained linear ranges extending north of the Appalachians and southward through them. Each of these species would presumably live in many varied habitats, considering the ranges as a whole, and would therefore be under selection pressures favoring a wide ecological tolerance. During a cold glacial period these genetically labile species would be those dispersing widely in the area south of the glaciers, as in rickeri (Fig. 102) and pygmaea (Fig. 104), and their southern out- post populations would be stranded by the next interglacial period with the possibility of forming new local endemic species. Second, some restricted species may in some fashion have gained or regained a wider ecological tolerance. Such events are suggested by rickeri, vivipara, and mystica. Each has a wide present range (Figs. 88, 96, 102) but no trace of geographic variation. Their relatives have small ranges. Altogether, these circumstances suggest that each evolved as a small population and became able to disperse widely while their relatives did not. SUMMARY The stonefly genus Allocapnia occurs only in eastern North America. It is associated with the temperate deciduous forest except for the species minima that reaches the northern tree line. All species emerge as adults during the winter or early spring. The genus represents a branch of the large and worldwide genus Capnia. Thirty-eight species of Allocapnia are known, of which a few pairs hybridize. On the basis chiefly of male and female genital characters, a highly probable fam- ily tree of Allocapnia has been constructed. When geographic distribution was integrated with this phylogeny, dispersal paths for present species and hypothetical ancestral species were adduced. The genus apparently evolved primarily in association with the Appalachian Mountain system, its neighboring ridges, and areas northeast of them. Six ancestral lineages spread to the Ozark- Ouachita Mountain region, but not synchronously, and the resultant western isolated populations evolved into distinct lineages, one of which spread to the Appalachians and reversed the process. A summation of geologic and paleoecologic evidence indicates that Allocapnia probably arose in the Pliocene from an eastern ancestor that also spread by a circumatlantic route to western Europe, the seg- regate there evolving into the vidua group of Capnia. The continuing eastern North American form evolved into Allocapnia. The evidence ) ( (ora) SUM MARY 89 at hand suggests that all the phylogenetic developments of the genus that we can deduce started late in the Pliocene when tectonic uplifts in central North America and subsequent intensified erosion had pro- duced an avenue of spring-fed streams that allowed dispersal of the genus between the Appalachian and Ozark-Ouachita systems. The evidence further suggests that the speciation pattern of Allocapnia is associated with the alternation of cold glacial and warm interglacial periods of the Pleistocene and comparable climatic oscillations occur- ring in late Pliocene. According to this suggested model of speciation, the genus as we know it is three or four million years old. ACKNOWLEDGMENTS In our studies of Allocapnia and the preparation of this report we have received a great deal of help from many persons. Without the wholehearted cooperation of the collectors we fondly call the Winter Stonefly Club we could not have begun to assemble the vast collection on which the study is based. The club membership is as follows: 90 D. W. Adams, University of Richmond, Richmond, Va. Lloyd E. Adams, Kittanning, Pa. L. Aggus, Fayetteville, Ark. Harold Alexander, Norfolk, Nebr. Lambert W. All, Cornell University, Ithaca, N.Y. R. T. Allen, University of Arkansas, Fayetteville, Ark. Connie Arnold, Southwest Texas State College, San Marcos, Tex. S. E. Banash, Wisconsin Conservation Dept., Antigo, Wis. T. C. Barr, University of Kentucky, Lexington, Ky. R. G. Beard, Cornell University, Ithaca, N.Y. Dan Benjamin, University of Wisconsin, Madison, Wis. C. O. Berg, Cornell University, Ithaca, N.Y. R. L. Blickle, University of New Hampshire, Durham, N.H. Anthony Bodola, Pennsylvania State University, University Park, Pa. ACKNOWLEDGMENTS 91 E. Bond, Canada Agricultural Research Institute, London, Ont., Canada Marvin E. Braasch, University of Kansas, Lawrence, Kans. W.S. Brooks, Ripon College, Ripon, Wis. W.L. Burger, Franklin College, Franklin, Ind. G. W. Byers, University of Kansas, Lawrence, Kans. J. M. Campbell, Entomology Research Institute, Ottawa, Ont., Canada Kelley R. Chadwick, R.R. 2, Richfield Springs, N.Y. Leland Chandler, Purdue University, Lafayette, Ind. William Childers, Illinois Natural History Survey, Urbana, III. J. A. Clark, Indiana Department of Conservation, Indianapolis, Ind. R. E. Cleary, State Conservation Commission, Des Moines, Iowa H. F. Clifford, University of Alberta, Edmonton, Alta., Canada R. H. Cohan, Franklin, Ind. K. W. Cooper, Dartmouth Medical School, Hanover, N.H. W. D. Countryman, Norwich University, Northfield, Vt. H. B. Cunningham (also C. H. and J. E. Cunningham), Auburn Uni- versity, Auburn, Ala. R. Dunean Cuyler, Rt. 1, Box 52, Durham, N.C. D. M. DeLong, Ohio State University, Columbus, Ohio R. J. Dicke, University of Wisconsin, Madison, Wis. W. H. Dieffenbach, Missouri Department of Conservation, Columbia, Mo. R. C. Dobson, Purdue University, Lafayette, Ind. T. C. Dorris, Oklahoma State University, Stillwater, Okla. C. K. Dorsey, West Virginia University, Morgantown, W.Va. S. W. Edwards, Southwest Texas State College, San Marcos, Tex. W. R. Enns, University of Missouri, Columbia, Mo. R. A. Evers, Illinois Natural History Survey, Urbana, Ill. Marjorie and T. M. Favreau, The American Museum of Natural History, New York, N.Y. R. L. Fischer, Michigan State University, East Lansing, Mich. William Flick, Cornell University, Ithaca, N.Y. Oliver Flint, U.S. National Museum, Washington, D.C. F. M. Ford, Austin Peay State University, Clarksville, Tenn. P. H. Freytag, University of Kentucky, Lexington, Ixy. Glenn Gentry, Game & Fish Commission, Nashville, Tenn. S. G. Gesell, Pennsylvania State University, University Park, Pa. R. C. Graves, Flint Community Junior College, Flint, Mich. J. F. Greene, State Department of Agriculture, Raleigh, N.C. J. D. Hall, Oregon State University, Corvallis, Ore. [a bo WINTER STONEFLY GENUS Allocapnia J. A. Harris, Raleigh, N.C. E. I. Hazard, Gainesville, Fla. M. M. Hensley, Michigan State University, East Lansing, Mich. R. E. Hesselschwerdt, Canberra, Australia J. W. Hines, Ohio State University, Columbus, Ohio S. W. Hitcheoek, Connecticut Agricultural Experiment Station, New Haven, Conn. Otis and Maxine Hite, Arkansas State University, State College, Ark. R. L. Hoffman, Radford College, Radford, Va. G. P. Holland, Entomology Research Institute, Ottawa, Ont., Canada J. R. Holman, Clemson University, Clemson, §.C. K. E. Hyland, Jr., University of Rhode Island, Kingston, R.I. F. P. Ide, University of Toronto, Toronto, Ont., Canada B. G. Isom, Tennessee Valley Authority, Wilson Dam, Ala. W. W. Judd, University of Western Ontario, London, Ont., Canada K. D. Kappus, Atlanta, Ga. E. W. King, Clemson University, Clemson, 8.C. J. M. Kingsolver, U.S. National Museum, Washington, D.C. D. Klinepeter, Purdue University, Lafayette, Ind. G. F. Knowlton, Utah State University, Logan, Utah L. V. Knutson, Cornell University, Ithaca, N.Y. C. E. Koelling, Hlinois State Museum, Springfield, Il. C. A. Kouskolekas, Auburn University, Auburn, Ala. L. A. Krumholz, University of Louisville, Louisville, Ky. M. E. Lea, Franklin, Ind. J. W. Leonard, University of Michigan, Ann Arbor, Mich. R. E. Lewis, Iowa State University, Ames, lowa L. A. Lueschow, Wisconsin Committee on Water Pollution, Madison, Wis. B. Lund, Cornell University, Ithaca, N.Y. J. F. McAlpine, Entomology Research Institute, Ottawa, Ont., Canada V.H. McCaskill, Clemson University, Clemson, 8.C. Rosemary MacKay, McGill University, Montreal, P.Q., Canada René Malouin, 8.J., Seminary of Quebec, Quebee City, P.Q., Canada J. E. H. Martin, Entomology Research Institute, Ottawa, Ont., Canada A. H. Mason, State Entomologist’s Office, Durham, N.H. D. L. Matthew, Purdue University, Lafayette, Ind. Mrs. W. Minshall, University of Louisville, Louisville, Ky. E C — .L. Mockford, Illinois State University, Normal, Ill. . Mohr, Atlanta, Ga. O° ACKNOWLEDGMENTS Me) [eN) . Moll, Eastern Illinois University, Charleston, Ill. . Moore, University of Michigan, Ann Arbor, Mich. . Morris, Department of Agriculture, St. John’s, Newfoundland . Morse, Wisconsin Conservation Department, Madison, Wis. .and R. A. Morse, Cornell University, Ithaca, N.Y. 1. Murvosh, Nevada Southern University, Las Vegas, Nev. . Narf, University of Wisconsin, Madison, Wis. nN V. Nebeker, National Water Quality Laboratory, Duluth, Minn. Mr. and Mrs. J. K. Neel, Potamological Institute, Louisville, Ky. S. E. Neff, Virginia Polytechnic Institute, Blacksburg, Va J. R. Nursall, University of Alberta, Edmonton, Alta., Canada D. R. Oliver, Entomology Research Institute, Ottawa, Ont., Canada A. Payne, Clemson University, Clemson, 8.C. L. Pechuman, Cornell University, Ithaca, N.Y. K. Peters, Franklin, Ind. V. Peterson, Research Entomology Laboratory, Guelph, Ont., Canada Martin Pfeiffer, New York Conservation Department, Ray Brook, N.Y. C. D. Pless, University of Tennessee, Knoxville, Tenn. E. C. Raney, Cornell University, Ithaca, N.Y. E. L. Reeves, University of California, Riverside, Calif. D. W. Renlund, Wisconsin Conservation Department, Madison, Wis. W. R. Richards, Entomology Research Institute, Ottawa, Ont., Canada C. A. and June Ross, Western Washington State College, Bellingham, Wash. Jean A. Ross, Athens, Ga. J.C. Roth, University of Michigan, Ann Arbor, Mich. G. L. and Anne Rotramel, University of California, Berkeley, Calif. R. J. Rubelmann, Maryland Water Pollution Control Commission, Annapolis, Md. M. W. Sanderson, Illinois Natural History Survey, Urbana, III. G. W. Saunders, University of Michigan, Ann Arbor, Mich. E. G. Schmieder, University of Pennsylvania, Philadelphia, Pa. I. M. Seligman, University of Illinois, Urbana, III. G. M. Simmons, Jr., Virginia Commonwealth University, Richmond, Va. R. M. Sinclair, State Department of Public Health, Nashville, Tenn. C. F. Smith, North Carolina State University, Raleigh, N.C. P. W. and Dorothy Smith, Illinois Natural History Survey and Uni- versity of Illinois, Urbana, Il. wea emaS Ie L. Ant B. 94 WINTER STONEFLY GENUS Allocapnia P. W. Smith, Wisconsin Department of Agriculture, Madison, Wis. K. M. Sommerman, U.S. Public Health Service, Fairbanks, Alaska A. H. Squires, U.S. Department of Agriculture, West Haven, Conn. L. J. Stannard, Illinois Natural History Survey, Urbana, III. Roland Stewart, Wisconsin Department of Conservation, Spooner, Wis. D. L. Thomas, University of Illinois, Urbana, III. EK. J. Udine, Pennsylvania State University, University Park, Pa. J.D. Unzicker, Illinois Natural History Survey, Urbana, III. R. L. Vannote, Tennessee Valley Authority, Chattanooga, Tenn. J. R. Vockeroth, Entomology Research Institute, Ottawa, Ont., Canada M. Wall, University of Arkansas, Fayetteville, Ark. H. D. Walley, Sandwich, Ill. J. F. Wanamaker, Principia College, Elsah, III. L. O. Warren, University of Arkansas, Fayetteville, Ark. R. E. Waters, Auburn University, Auburn, Ala. D. W. Webb, Illinois Natural History Survey, Urbana, III. D. A. Webster, Cornell University, Ithaca, N.Y. G. B. Wiggins, Royal Ontario Museum of Zoology, University of Toronto, Toronto, Ont., Canada J. R. Williamson, Department of Agriculture, St. John’s, Newfound- land R. B. Willson, Michigan State University, East Lansing, Mich. D. M. Wood, McMaster University, Hamilton College, Hamilton, Ont., Canada D. L. Wray, State Department of Agriculture, Raleigh, N.C. Steve Wunderle, Eastern Illinois University, Charleston, Ill. W. D. Youngs, New York Conservation Department, Ray Brook, N.Y. Valuable study efforts and curatorial assistance were provided by T. Yamamoto, G. Rotramel, T. L. Harris, and R. T. Allen. Expert clerical assistance was afforded by Mrs. Bess White, Mrs. Bernice P. Sweeney, and Mrs. Dorothy Gailus. Figures 1-3 were done by Dr. C. O. Mohr, the illustrations of the male genitalia by Mrs. Alice Prickett, those of the female genitalia by Mrs. Diana Slavens, and the maps were executed by Mr. Richard Sheets. Mrs. Prickett was invaluable in assembling the plates. Although they are not responsible for the conclusions we reached, we received valuable geological advice from Drs. J. C. Frye, H. B. Willman, and J. Kempton of the Illinois Geological Survey and Dr. ACKNOWLEDGMENTS 95 GC. A. Ross of Western Washington State College. Welcome advice and encouragement were received from Drs. H. B. Mills, P. W. Smith, and George Sprugel, Jr., of the Illinois Natural History Survey. Financial support for a considerable part of the project was afforded by the National Science Foundation. To all these and to others whose names we may have omitted inad- vertently we extend our sincere thanks. LITERATURE CITED Bearp, J. H. 1969. Pleistocene paleotemperature record based on planktonic foramin- ifers, Gulf of Mexico. Gulf Coast Assoc. of Geol. Soc., Trans. 19:535-553. Buack, Ropert F. 1964. Periglacial phenomena of Wisconsin, north central United States. 6th Intern. Congress on Quarternary. Report vol. 4, Periglacial sect., pp. 21-28. 1965. Ice-wedge casts of Wisconsin. Trans. Wis. Acad. Sci., Arts and Letters 54:187-222. Brown, R. J. E. 1965. Factors influencing discontinuous permafrost in Canada. Int. Assoc. Quart. Res., 7th Int. Congress, Abstract Genl. Sessions, p. 47. BURMEISTER, HERMAN 1839. Plecoptera, in Handbuch der Entomologie 2:863-881. T. C. F. Enslin, Berlin. Burzer, K. W. 1964. Environment and archeology. Atoline Publ. Co., Chicago. 524 pp. CLAASSEN, P. W. 1924. New species of North American Capniidae (Plecoptera). Can. Ent. 56 (2) :43-48. 1928. Additions and corrections to the monograph on the Plecoptera of North America. Ann. Ent. Soc. Am. 21 (4) :667-668. 96 LITERATURE CITED 97 1940. A catalogue of the Plecoptera of the world. Cornell Univ. Exp. Sta. Memoir 232:1-235. Dietz, Rosert §., and JoHN C. HoLpEN 1970. The breakup of Pangaea. Sci. Am. 223 (October): 30-41. FERNALD, M. L. 1925. Persistence of plants in unglaciated areas of Boreal America. Mem. Am. Acad. Arts, Sei. 15:257-342. Fircu, A. 1847. Winter insects of eastern New York. Am. J. Agr. and Sci. 5:274-284. Frison, T. H. 1929. Fall and winter stoneflies or Plecoptera of Illinois. Bull. Ill. Nat. Hist. Surv. 18(2) :340-409. 1935. The stoneflies, or Plecoptera, of Illinois. Bull. Ill. Nat. Hist. Surv. 20(4) :275-471. 1942. Studies of North American Plecoptera with special reference to the fauna of Illinois. Bull. Ill. Nat. Hist. Surv. 22(2) :236-355. Frye, JoHN C., H. D. Grass, J. P. Kempron, and H. B. WitLMAan 1969. Glacial tills of northwestern Illinois. Ul. State Geol. Surv. Cire. 437 :1-45. Frys, JoHN C., H. D. Guass, and H. B. Wittman 1968. Mineral zonation of Woodfordian loesses of Illinois. Ill. State Geol. Surv. Cire. 427:1-44. Hanson, J. F. 1942. Studies on the Plecoptera of North America. III. Allocapnia. Bull. Brooklyn Ent. Soc. 37:81-88. 1946. Comparative morphology and taxonomy of the Capnidae (Plecop- tera). Am. Midland Naturalist 35:195-249. 1960. A case of hybridization in Plecoptera. Bull. Brooklyn Ent. Soc. 55: 25-34. Hanson, J. F., and J. AUBERT 1952. First supplement to the Claassen catalogue of the Plecoptera of the world. The Authors, U.S.A. HENNIG, W. 1966. Phylogenetic systematics. Univ. of Illinois Press, Urbana. 265 pp. fpLies, J. 1960. Phylogenie und Verbreitungsgeschichte der Ordnung Plecoptera. Verhandlung Deuts. Zool. Gesellschaft in Bonn, 1960:585-594. 1965. Phylogeny and zoogeography of the stoneflies. Ann. Rey. Ent. 10: 117-140. 1966. Katalog der rezenten Plecoptera. Das Tierreich 82. 632 pp. JENNESS, J. E. 1960. Late Pleistocene glaciation of eastern Newfoundland. Bull. Geol. Soc. Am. 71:161-179. NEWPORT, GEORGE 1851. On the anatomy and affinities of Pteronarcys regalis Newm.: with a postscript, containing descriptions of some American Perlidae, together with notes on their habits. Trans. Linn. Soe. London 20(3) :447-452. 98 WINTER STONEFLY GENUS Allocapnia Ricker, W. E. 1935. New Canadian perlids (part II). Can. Ent. 67 (12) :256-264. 1938. Notes on specimens of American Plecoptera in European collections. Roy. Can. Inst. Trans. 22:129-256. 1950. Some evolutionary trends in Plecoptera. Proc. Indiana Acad. Sci. 59 :197-209. 1952. Systematic studies in Plecoptera. Indiana Univ. Publ. Sci. Series no. 18, 1-200. RosuHo tt, J. N., C. Em1iant, J. Geiss, F. F. Koczy, and P. J. WANGERSKY 1961. Absolute dating of deep-sea cores by the Pa™/Th* method. J. Geol. 69:162-185. Ross, C. A. 1963. Structural framework of southernmost Illinois. Illinois State Geol. Surv. Cire. 351. 23 pp. 1965. Late Cenozoic topography and climatic changes. Pp. 584-585, in The Quarternary of the United States (H. E. Wright, Jr., and D. G. Frey, eds.). Princeton Univ. Press, New Jersey. x + 922 pp. Ross, H. H. 1956. Evolution and classification of the mountain caddisflies. Univ. Illi- nois Press, Urbana. vi + 213 pp. 1964. New species of winter stoneflies of the genus Allocapnia (Plecoptera, Capniidae). Ent. News 75(7) : 169-177. 1965. Pleistocene events and insects. Pp. 583-596, in The Quarternary of the United States (H. E. Wright, Jr., and D. G. Frey, eds.). Princeton Univ. Press, New Jersey. x + 922 pp. Ross, H. H., and P. H. Freytac 1967. Remarkable sympatry in the winter stoneflies Allocapnia indianae and A. ohioensis, a pair of sister species. Ohio J. Sci. 67 (4) :228-252. Ross, H. H., and W. E. Ricker 1964. New species of winter stoneflies, genus Allocapnia (Plecoptera, Cap- niidae). Trans. Ill. Acad. Sei. 57 (2) :S8-93. Ross, H. H., G. L. Rorramet, J. E. H. Martin, and J. F. McA.pine 1967. Postglacial colonization of Canada by its subboreal winter stoneflies of the genus Allocapnia. Can. Ent. 99(7) :708-712. Ross, H. H., and T. Yamamoto 1966. Two new sister species of the winter stonefly genus Allocapnia (Plecoptera, Capniidae). Ent. News 77 (10) :265-267. 1967. Variations in the winter stonefly Allocapnia granulata as indicators of Pleistocene faunal movements. Ann. Ent. Soc. Am. 60(2) :447-458. Srarpson, G. G. 1944. Tempo and mode in evolution. Columbia Univ. Press, New York. 237 pp. SmIitTH, P. W. 1957. An analysis of post-Wisconsin biogeography of the prairie peninsula region based on distributional phenomena among terrestrial vertebrate populations. Ecology 38:205-218. LITERATURE CITED 99 Wats, B. D. 1862. List of the Pseudoneuroptera of Illinois contained in the cabinet of the writer, with descriptions of over 40 new species and notes on their structural affinities. Proc. Acad. Nat. Sei. Phila. pp. 362-367. WitimaN, H. B., and JoHN C. FryYE 1969. High-level glacial outwash in the driftless area of northwestern Illi- nois. Ill. State Geol. Surv. Cire. 440:1-21. WyYNNE-Epwarps, V. C. 1937. Isolated arctic-alpine floras in eastern North America: . 2° € €& . €€€ E = oS Sn ise so 56 6s. rm 2 ly 2. WwZWEe SS Tris SS in S | Tot ES wi: Ps ee ee | ee a) ee) ces ee ee: ee) ee ee es ee ec | | Pape oeece eo | I ~) ) a a thsi Q | SG i fee a ee = Saas Soe | Si aot Orage <— 2 = > = TMH! CGS Fa EL Q sSlioe SS ,vFPslagsgra mS TEQg BAS Ses ToS EH SG S F€ISS LSESSELSS SSB 2 2 TCGOPtWH KC€SSceEsssesgesSs Q (8) | Epiproct (6) snap-like ’5) Epiproct forke: Ai ay ‘Tergite 7 with proci Aplee BY Ventral lobe lost 3) Mesofurcasternum a triangular @ Metafurcasternum reduced ‘Hind wing Capniid lacks R3z and Rs Ancestor Fic. 4. Preliminary phylogenetic outline of the family Capnidae. Fur., Eu- rasian; Hol., Holarctic; N. Am., North American. we \ \ SS Sa = bt Fic. 5. Terminal segments of male Capnia columbiana Claassen, illustrating V-shaped epiproct. (After Nebeker and Gautin.) Fic. 6. Terminal segments of male Capnia vidua Klapalek, illustrating the double-limbed epiproct of the appressed type. (After Aubert.) Fic. 7. Dorsal aspect of ninth segment of male Capnia glabra Claassen. bt, basal thickening (in Figs. 8-11 also). Fic. 8. Basal thickening of ninth tergite of male Capnia manitoba Claassen. Fic. 9. Basal thickening of ninth tergite of male Capnia columbiana. Fic. 10. Dorsal aspect of male ninth segment of Capnia vidua. Fic. 11. Dorsal aspect of male ninth segment of Allocapnia loshada. 108 ——— ——-—-—dorsal process _-epiproct base \ “————upper limb dorsal process~ — —~ — lower limb DORSAL VIEW vivipara Fic. 12. Terminal abdominal segments of male Allocapnia vivipara. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth ter- gite; D, posterior aspect of dorsal hump of seventh tergite. 109 Fics. 13, 14. Terminal abdominal segments of male Allocapnia brooksi and tennessa. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 110 Fias. 15, 16. Terminal abdominal segments of male Allocapnia malverna and mohri. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal pro- cess of eighth tergite. polemisis o Fics. 17, 18. Terminal abdominal segments of male Allocapnia recta and polemistis. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D-H, variants of dorsal process of eighth tergite, lateral aspect. D, ancestral type; G, H, derived type; F, F, intermediate types. loshada virginiana Fics. 19, 20. Terminal abdominal segments of male Allocapnia loshada and virginiana. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 113 fumosa rs > granulata : <=} Fics. 21, 22. Terminal abdominal segments of male Allocapnia fumosa and granulata. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 114 warren unzickert Fias. 28, 24. Terminal abdominal segments of male Allocapnia warreni and unzickeri. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 115 frisonl Fics. 25, 26. Terminal abdominal segments of male Allocapnia frisoni and peltoides. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 116 Fias. 27, 28. Terminal abdominal segments of male Allocapnia wrayi and zekia. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite. 117 Fias. 29, 30. Terminal abdominal segments of male Allocapnia mystica and illinoensis. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. ~ -~ D forbesi D ozarkanag 32 . Terminal abdominal segments of male Allocapnia forbesi and Fics; ol,.3 9 ozarkana. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal el process of ghth tergite; D, posterior aspect of dorsal hump of seventh tergite. 119 Fic. 33. Terminal abdominal segments of male Allocapnia pechumani. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. 120 minina 35) Fics. 34, 35. Terminal abdominal segments of male Allocapnia maria and minima. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. Fics. 36, 37. Terminal abdominal segments of male Allocapnia curiosa and jeanae. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. D 2 Scunninghami Fics. 38, 39. Terminal abdominal segments of male Allocapnia sandersoni and cunninghami. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of sev- enth tergite. C rickerl D stannarad Fias. 40, 41. Terminal abdominal segments of male Allocapnia rickeri and stannardi. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. 124 perplexa C—— , Fias. 42, 43. Terminal abdominal segments of male Allocapnia zola and per- plexa. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite; £, dorsal aspect of lower hmb of epiproct (normally hidden under upper limb) ; F, dorsal aspect of variant eighth tergite. ————— C aurora Fias. 44, 45. Terminal abdominal segments of male Allocapnia pygmaea and aurora. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite, showing two variants (see text). Indianae Fias. 46, 47. Terminal abdominal segments of male Allocapnia ohioensis and indianae. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh tergite. D smitht D hivicola Frias. 48, 49. Terminal abdominal segments of male Allocapnia smithi and nivicola. A, lateral aspect; B, dorsal aspect; C, posterior aspect of dorsal process of eighth tergite; D, posterior aspect of dorsal hump of seventh ter- gite; H, variant of epiproct, dorsal aspect. 128 50B fennessa brooksi Fic. 50. Apical tergites of female Allocapnia. A, tennessa; B, brooksi. st aa SR ee ksi S| broo ny bat a recta 54 loshada 55 129 \ ‘ } it J ohri . eaten, NaN FARE fi Nye \ f Sy \* QR: j we ; ' jd PY it i \ d \ 4 7 fai i L's % virginiana 56 Fics. 51-56. Apical sternites of female Allocapnia. 51, brooksi; 52, vivipara; 53, mohri; 54, recta; 55, loshada; 56, virginiana. 6, 7, 8, sternites. \ gees oe 0 Tr aaeeeetaeT he e em oa - ei hi Ri re } \ See he oh my C ee sO , if j > B . £456 unzickeri ° UNZICKEI 584 \ X 590A | Ses frisont frisoni 598 —peltoides ©° Fias. 57-60. Apical sternites of female Allocapnia. 57, granulata; 58A, B, variants of wnzickeri; 59A, B, variants of frisoni; 60, peltoides. 131 se ea LDU yp, a UE — ree, oe x 4 s 4 i: u # ul ; 4 j 4 b a ilinoensis °° Xe , forbesi © Fics. 61-66. Apical sternites of female Allocapnia. 61, wrayi; 62, mystica; 63, illinoensis ; 64, forbesi; 65, ozarkana; 66, pechumant. pechuman/ © * : of 4 X ; x ~\ - f : PL sf By Jeanae °° — sandersoni "\cunninghami’* Fics. 67-72. Apical sternites of female Allocapnia. 67, maria; 68, minima; 69, curiosa; 70, jeanae ; 71, sandersoni; 72, cunninghami. 153 Stannard ° rickeri °° Woh f 76 l \ sug j pygmaea he Fics. 73-77. Apical sternites of female Allocapnia. 73, rickeri; 74, stannardi; 75, zola; 76, perplexa; 77, pygmaea. Inset at side, profile of seventh and eighth sternites. perplexa 134 a el ; 78 Qurorda a ; 4 { (aS _ ihe She | a a. A. : + pea e ao % neat sages . a : 4 a : % SS 2 4 3 indianae ®' smithi 82 — nivicola ® Fics. 78-83. Apical sternites of female Allocapnia. 78, aurora; 79, ohioensis ; 80, 81, variants of indianae ; 82, smithi; 83, nivicola. ©, ¢ : 4 135 oo. pean C ha Fic. 84. Male genitalia of Allocapnia granulata. Upper row (a), typical of eastern populations; lowest row (c), typical of Ozark-Ouachita populations; middle row (6), intermediate type. (From Ross and Yamamoto, 1967.) if Vi / \N Fic. 85. Terminal abdominal segments of Allocapnia minima (A), maria (E), and three apparent hybrids (B, C, D). (From Hanson, 1960.) 137 sbuim .O 61) vivipara fennessa brooks/ sg puosy (12) (2) jO1Btysan loshada polemistis recta. mohri ma/verna virginiana 189 22) aj010das Sg pud SZ re) mo| ‘j0NI10 18 0 sBuim Buo| ze) aAISSOW (02) sqqouy A\jo1paw pasny fumosa warren’ unzickerl granulata peltoides frisont zekia wray! mystica /Minoensis pajDaaja 18 9 (©) aytuoiusnd an e2 \ © G2) | (r2) (S) (9) 18,0 mestcy abuoys ou (6) é ssad0ud |oSsu0p (01) YIM 12 O eed. ‘an @) forbes/ (3) ozarkana curiosa. pechumani = maria minima Jeanae stannaral (8) ricker! sandersoni cunningham zola perplexa pygmaea gurora , ohioens!s indianae smithi nivicola G2) | @!) @2) pasny Ajjo1jsa0d Sg puo SZ 180 / i I @!) aAalssow ‘ybiy (2) paqqouy Ot sg puosz & Pe n jo ay wit’? pasny Ai pros } do y joo1do UyIMS8 JOPIM PP Ge) ayOyuspl4y 18,9G>) oe) Fic. 86. Phylogenetic chart of Allocapnia. Numbers refer to hypothetical ancestral species explained in the text (number 31 not used). — Co (04) ph ming TI OCU LUPLAUAVLTIL SOIL Y' y i Ad dack Mountains Ap jalachian Mountains' + Ar Arbuckle Mountains CA Cincinnati Arch cP Cumberland Plateau 7 DA Driftless Area 10 Illinois Ozarks NU Northeastern Uplands: Ou Ouachita Mountains OP Ozark Plateau PP. Piedmont Plateau eet Wichita Mountains , Z Wisconsinan Glacial Lobes Previous Glacio Lobes’ Fic. 87. The bulk of the distribution records for all species of Allocapnia. Negative records are not shown, including many localities at which other genera of winter stoneflies were collected, west through South Dakota and southwest to Brownsville, Texas. For more northern and eastern records, see Figs. 99 and 100. 139 aes Ui, | Y YY yes: Se L// et s Fo -viviennn = We aro0Kst_ “STENNESSA | 0 i H Mississippi) Embayment Ad Adirond gins Ap Appalachian M Ar Arbuckle Mo CA Cincinnati Arch cP Cumberland Plateau DA Driftless o 0 Illinois O NU ~ Northeaster PP Piedmont Plateau Wi Wichita Mountains Wisconsincn Glacial Lobes Previous Glacial Lobes Fra. 88. Distribution of the Allocapnia vivipara group. 140 | YY Adirondack Mountains . cp’ \ \ \ PP “Ar NN Ap» Appalachian Mountains . Ap \ Ar Arbuckle Mountains POLEMISTIS ‘ CA Cincinnati Arch , H CP»Cumberland Plateau H | cerasian WS { DA Oriftless Area i ' H ¥ 10 IMinois Ozarks ox H A—MALVERNA NU Northeastern Uplands aan ‘ \ Ou Ouachita Mountains { c fo) \ in -\ oP Ozork Plateau 7 ' aes aia Se PP. Piedmont Plateau | Soe 1 Wi Wichita Mountains | ck ! aor CA Wisconsinan Glacial Lobes | Previous Glacial Lobes | Fic. 89. Distribution of the Allocapnia recta group except for recta. 141 Adirondack Mountains Appalachian Mountains Arbuckle Mountains Cincinnati Arch Cumberland Plateau Oriftless Area Iinois Ozarks ) Northeastern Uplands Ouachita Mountains H 7 a \ = fe Ozark Plateou \ =~ ee meas : Piedmont Plateau / z | « ) 4 Wichita Mountains (£44 Wisconsinan Glacial Lobes 4 ES Previous Glaciol Lobes Fic. 90. Distribution of Allocapnia recta. Circles with crosses are hybrid flocks of ancestral and derived forms, solid circles are the derived form only. 142 ANCESTRAL FQRM DERIVED FORM \:/ ee Fic. 91. Postulated stages in the evolution and dispersal of the ancestral and derived forms of Allocapnia recta (see also Table p. 62). For explanation, see text (p. 63). 145 y, , te) App, Yj y, i Yi VW Z Y x Y A i Hy ‘ y 4 x S 4 i 4 } { ‘ , { y 5 i t i v re Yi Ga yy 4 > 2, AN ’ === === Gy Eeu MMMJI\ Pea Spe a N Ad»-Adirondack Mountains Ap. Appalachian Mountains Ar Arbuckle Mountains CA Cincinnati Arch CP: Cumberland Plateau DA Driftless Area 10 Wlinois Ozarks NU~-Northeostern Uplands Ou Ouachita Mountains oP Ozark Plateau PP Piedmont Plateau Wi Wichita Mountains aa Wisconsinan Glacial Lobes ISS Previous Glaciol Lobes Fria. 92. Distribution of Allocapnia virginiana. SESSA °d0 ; = | AM oa ‘Ou | "UNZICKERI : Ad Adirondack Mountains 4 ‘ {* e NCS Ap» Appalachian Mountains Te BEIT IDES | F ef Ap \ ; ie Arbuckle Mouniaia ae ‘ a > ¢ CA Cincinnati Arch | CP-Cumberland Plateau i) ——— H tone é DA Oriftless Area H | - 10 Iinois Ozarks | H e NU--Northeastern Uplands ‘ { Ou Ouachita Mountains{ oP ‘Ozork Plateau ? PE Piedmont Plateau: \ Wi ‘Wichita Mountains Wisconsinan Glacial Lobes! Previous Glacial Lobes, ~ j Fic. 93. Distribution of the Allocapnia granulata group except for granulata. 145 Adirondack Mountains Appalachian Mountains Arbuckle Mountoins Cincinnaty Arch Cumberland Plateau Oriftless Areo Ilinois Ozarks Northeastern Uplands Ouachita Mountains Ozark Plateau Piedmont Plateau Wichita Mountains Wi (3A Wisconsinan Glacial Lobes Previous Glacial Lobes oN. a SS NN ay Ne ~ » 20 Vos Fic. 94. Distribution of Allocapnia granulata. For explanation of numbers, see text (pp. 29-80) and Fig. 95. | } =o Cae Oe Aa eae, | a Fra. 95. Postulated stages in the evolution and dispersal of the four popula- tions of Allocapnia granulata (see Fig. 94). For explanation, see text (pp. 29-30, 64-65). ey SSsa““vr Fic. 96. Distribution of the Allocapnia mystica group. Adirondack Mountains Ap Appalachian Mountains Ar Arbuckle Mountains CA Cincinnati Arch cP. Cumberland Plateau DA Oriftless Area 10 IMinois Ozarks NU Northeastern Uplands Ou Quochita Mountains oP Ozark Plateau PP Piedmont Plateau wi Wichita Mountains A Wisconsinon Glacial Lobes Previous Glaciol Lobes 148 Adirondack Mountains Ap--Appalachian Mountains Ar Arbuckle Mountains CA Cincinnati Arch CcP»-Cumberland Plateau DA Oriftless Area ile} Minois Ozarks NU--Northeastern Uplands Ou Quochita Mountains oP Ozark Plateau PP Piedmont Plateau Wi Wichita Mountains Wisconsinan Glacial Lobes BY Previous Glacial Lobes ae Fic. 97. Distribution of Allocapnia illinoensis. Arrows indicate probable post- Pleistocene dispersals. 149 SS SS SE VZ i, iy A 4 } j u Ay i \ f O (acd I Mississippi Emba sees ——- \ ; i : ----& Ad Adirondack Mountains i Wi t Ap Appalachian Mountains ' Ar Arbuckle Mountains i cA Cincinnati Arch { cP Cumberland Plateau : DA Oriftless Area ' Te) Mlinois Ozarks ! NU Northeastern Uplands 7 Ou Quochita Mountains oP Ozark Ploteou PP. Piedmont Piateou Wi Wichita Mountains ZA Wisconsinan Glacial Lobes ISS) Previous Glacial Lobes Fig. 98. Distribution of Allocapnia curiosa, forbesi, and ozarkana. 95° Fic. 99. Distribution of Allocapnia maria and pechumani. Hybrid populations are denoted by a number, representing an approximation of the percentage of genetic preponderance of the species indicated by the symbol. 151 Fic. 100. Distribution of Allocapnia minima. me CLL 2 NAS q u oe, & ------ ~~ pare ences = Zs ( \ a ) a& i om ey ¥ GQ > [Pte Grew Sees ee x 4 SoS Adirondack Mountains Ap» Appalachian Mountains Ar Arbuckle Mountains CA Cincinnoti Arch’ CP-Cumberland Plateau = * DA Driftless Areo ile} Mlinois Ozarks * NU» Northeastern Uplands 1 Ou Ouachita Mountains | op Ozark Plateau PP Piedmont Plateau Wi Wichita Mountains EA Wisconsinan Glacial Lobes SS) Previous Glacial Lobes Fria. 101. Distribution of Allocapnia jeanae. 153 S77 Adirondack Mountains Appalachian Mountains Arbuckle Mountains Cincinnati Arch Cumberland Plateau Oriftless Area Ilinois Ozarks Northeastern Uplands Ouachita Mountains Ozark Plateau Piedmont Plateau Wichita Mountains = CA Wisconsinan Glacial Lobes Previous Glacial Lobes fe my i —. /] S aN NN Fra. 102. Distribution of Allocapnia rickeri. 154 XS WO ely SANDERSONI __PERPLEXA cp | \ Ad Adirondack Mountains Ap Appalachian Mountains Ar Arbuckle Mountains CA Cincinnati Arch cP. -Cumberland Plateau DA Oriftless Area 10 Iinois Ozarks NU Northeastern Uplands Ou Ouachita Mountains 52 op Ozark Plateau | 7 oe PP. Piedmont Plateau Wi Wichita Mountains EA Wisconsinan Glacial Lobes SS) Previous Glacial Lobes Fic. 103. Distribution of other members of Allocapnia rickeri group. The record for perpleza is the light area in the middle of the dots for cunninghami. Fic. 104. Distribution of Allocapnia pygmaea. Arrows indicate probable routes of post-Pleistocene dispersal. — or [op) | 54 y 2% Sow “Ar Ad Adirondack Mountains Ap» Appalachian Mountains Ar Arbuckle Mountains CA Cincinnati Arch CP»-Cumberland Plateau DA Driftless Area 10 Mlinois Ozarks NU--Northeastern Uplands Ou Ouachita Mountains op Ozark Plateau pp Piedmont Plateau wi Wichita Mountains EA Wisconsinan Glacial Lobes Previous Glacial Lobes Fic. 105. Distribution of Allocapnia aurora (open circle). The “x” ’s are popu- lations of nivicola having possible aurora x nivicola hybrids. 157 Arch Cumberland Plateau Ilinois Ozarks NU Northeastern Uplands Ozark Plateau Oriftless Area Piedmont Ploteau Cincinnati Wichita Mountains aa Wisconsinan Glacial Lobes Arbuckle Mountains Ouachita Mountains Previous Glacial Lobes Ad Adirondack Mountains Ap Appalachian Mountains Ar CA cP DA 10 Ou op PP Wi a Mississippi) Embayment RUSE NNEC at LOENSIS . tribution of Allocapnia oh 1S D Fia. 106. 158 Slee OO , y 7 t | ite FL 2 Be) %% ee oP ee a hed De LLU Mn «~ ty Y My ™ S RO SSAA Ad» Adirondack Mountains ~ ApAppalachian Mountains f Ar Arbuckle Mountains or CA ~Cincinnati Arch CP»Cumberland Plateau ee Driftless Area a Illinois Ozarks NU--Northeastern Uplands Ou Ouachita Mountains soo Ozark Plateau Piedmont Plateau Wichita Mountains Wisconsinan Glacial Lobes Previous Glaciol Lobes yu ) a GILBERT Fic. 111. A EVENTS FIELD PLANKTONIC FORAMINIFERS: YEARS WAR' Il \ MW Yl \ CONTINENTAL GLACIATION Frye, 1962 POST GLACIAL WISCONSINAN ILLINOIAN YARMOUTHIAN KANSAN ~-—---- -4 AFTONIAN NEBRASKAN PLIOCENE APPROXIMATE CONTINENTAL mina FIELD wont FIELD peveict & summary of pertinent features concerning dating, climates, PLANKTONIC DATUMS GULF OF MEXICO LAST COMMON GLOBOQUADRINA HEXAGONA LAST ABUNDANT GLRT. TRUNCATUL/NO/DES 95% LEFT COILING SPHAEROIDINELLA DEHISCENS UNCOMMON ABOVE THIS LEVEL EXTINCTION OF DISCOASTERS EXTINCTION GLOBOROTALIA MIOCENICA AND COILING CHANGE GLRT. MENARDI// COMPLEX INITIAL APPEARANCE GLRT. TRUNCATULINOIDES EXTINCTION GLOBOQUADRINA ALTISPIRA INITIAL APPEARANCE GLRT TOSAENSIS INITIAL APPEARANCE SPHAEROIDINELLA DEHISCENS (WITH FLANGE LIKE MULTIPLE APERTURES) EXTINCTION GLOBOROTALIA MARGARITAE and name correlations for the Pleistocene and late Phocene in southeastern North America, based on planktonic organisms in cores from the Gulf of Mexico. (From Beard, 1969.) INDEX Names printed in italics are synonyms. Numbers in italics indicate principal references. Agapetus celatus group, 80 Agapetus comatus group, 80 Agapetus fuscipes group, 80 Alabama, 24, 26, 32, 41, 46, 49, 76, 83 Allocapnia, 2, 3, 4, 5, 6, 79; ancestor of, 52; diagnosis, 7; early history of, 79 Allocapnia speciation pattern, 84 Amount of change, 77 Ancestral synchrony, 81 Ancestral types, 73 Appalachian area, 70, 73, 76 Appalachian Mountains, 64, 66, 68, 76, 80, 81, 88, 89 Appalachian-Ozark corridor, 80 Appalachian-Ozark dispersal, 81 Arbuckle Mountains, 29, 30, 65 Arkansas, 22, 23, 27, 29, 32, 34, 40, 41, 73, 76, 80 Arkansas Ozarks, 64 atra group, 4 aurora, Allocapnia, 15, 17, 46, 58, 71, 73, 78 Avalon Peninsula, 69 Aves, 6 Bering Bridge, 80 bifrons group, 4 brooksi, Allocapnia, 11, 17, 19-20, 54, 61, 78, 85 Caddisflies, 2, 80 Capnella, 3, 7 Capnia, 3, 4, 5, 6, 51, 88 Capniidae, 2, 3, 79; ancestral, 3 Capnioneura, 4 Cenozoic dispersals, 79 Cincinnati Arch, 61, 67, 70, 71, 80 Coastal Plain, 76 Cold glacial periods, 89 Collembola, 1 columbiana group, 4, 5 Conecuh County, 76 Connecticut, 37, 38, 44, 45 cornuta, Allocapnia, forbesi var., 35, 36 Crane flies, 2 Cumberland Plateau, 28, 61, 64, 72, 76 Cumberland River Valley, 28 cunninghami, Allocapnia, 12, 17, 42-40, 57, 70, 85 curlosa, Alloecapnia, 138, 17, 39, 56, 67, 78 165 164 WINTER STONEFLY GENUS Allocapnia Derived character condition, 50 Disjunct populations, 78 Distribution records, 8 District of Columbia, 21, 24, 29, 32, 41, 45, 46, 49 Downstream transport, 60 Duration of time, 77 East, 85 Eastern Asia, 80 Eastern North America, 80 Ecology, comparative, 74 elongata group, 4, 5 Epiproct, 52 Eucapnopis, 4 Eurasia, 79 Europe, 82 excavata group, 4 Farmdalian substage, 82, 85 Females, key to, 15 Female sternites 7 and 8, 51 forbesi, Allocapnia, 14, 15, 35-36, 56, 67, 78 forbesi group, 53; dispersal, 67; phylog- eny, 56; taxonomy, 34 frisoni, Allocapnia, 12, 18, 30, 64, 78 fumosa, Allocapnia, 11, 26-27, 55, 64, 85 Gaspé Peninsula, 69 Georgia, 24, 26, 32, 41, 46 granulata, Allocapnia, 12, 18, 27, 28-30, 56, 64, 75, 76, 78, 82, 83, 85; intraspe- cific variation, 64 granulata, Capnella, 7, 28 granulata group, 27, 53; dispersal, 64; phylogeny, 55; taxonomy, 26 Grasshoppers, 1 Great Lakes, 84 Great Smoky Mountains, 27, 42, 64, 70, 85 gregsonl group, 4 Gulf Coast, 80 Gulf of Mexico, 83 Gulf of St. Lawrence, 69 hingstoni group, 4, 5 Hybridization, 68, 73 Hybrid origin, 58 Hybrids, indianae x ohioensis, 12; ma- ria X minima, 13; maria x pechumani, 13, 36, 68; nivicola x aurora, 14, 46, 49, 73; nivicola x smithi, 49 Hybrid swarms, 37 Ice blocks, 60 illincensis, Allocapnia, 13, 16, 17, 33, 55, 78 illinoensis group, 63; dispersal, 66; phy- logeny, 55; taxonomy, 33 Illinoian glacial stage, 84 Illinois, 21, 24, 29, 32, 38, 35, 48, 49, 65, 67, 71, 72, 75 Illinois Ozarks, 76, 80 Ulinois Ozarks corridor, 76 incisura, Capnella, 38 Indiana, 21, 24, 29, 32, 35, 41, 47, 49, 67, 75 indianae, Allocapnia, 12, 17, 47, 58, 72, 73, 75, 78, 82 Interglacial stages, 87 Interspecific competition, 86 Intra-Wisconsinan events, 82 Iowa, 21, 29, 41, 71 Isceapnia, 4 Jackson Dome area, 76, 80 jeanae, Allocapnia, 15, 40, 85 jeanae group, 53; dispersal, 70; phylog- env, 57; taxonomy, 39 Kansan glacial stage, 84 Kansas, 21, 29, 41, 75 Kentucky, 21, 24, 29, 30, 32, 35, 39, 41, 43, 44, 45, 47, 48, 49, 73, 76 Keys to species, use of, 9 Leafhoppers, 1 Leuctridae, 2,3 Local endemics, evolution of, 85 loshada, Allocapnia, 10, 19, 25, 54, 62, 78, 85 Louisiana, 22, 29, 65, 76, 80 Maine, 24, 33, 37, 38, 44, 45 Male eighth tergite, 51 Male seventh tergite, 51 Males, key to, 10 malverna, Allocapnia, 11, 19, 22-23, 51, 52, 54, 62, 76 Mammalia, 6 manitoba group, 4, 5 Man-made discontinuities, 71 maria, Allocapnia, 13, 18, 37-38, 56, 57, 67, 68, 70 Maryland, 21, 24, 29, 33, 37, 39, 41, 45, 46, 49 Massachusetts, 24, 37, 38, 45, 49 Mean annual temperature, 86 Michigan, 21, 29, 38, 45 Midwest, 79 Mid-Wisconsinan substages, 87 minima, Allocapnia, 11, 18, 37, 38-39, 56, 68, 74, 77, 88 minima?, Capnia, 22 minima, Perla, 38 minima, tachytely in, 68 Minnesota, 21, 29, 33, 38, 41, 45, 71, 85 Mississippi, 24, 26, 29, 41, 76, 80 Mississippi Embayment, 76, 80 Mississippi River Valley, 76, 85 Missouri, 21, 23, 29, 32, 41, 45, 65, 72, 73, 75, 76, 85 mohri, Allocapnia, 10, 19, 23, 54, 62, 85 Monroe Uplift, 76, 80 mystica, Allocapnia, 15, 19, 32, 55, 56, 58, 66, 75, 76, 77, 86, 87 mystica group, 34, 53; dispersal, 65; phylogeny, 55; taxonomy, 31 nana complex, 51 Nebraskan glacial stage, 84 Nemocapnia, 4 Nemouridae, 2, 3 New Brunswick, 36, 37, 38, 44, 45, 49 Newfoundland, 38, 69, 70 New Hampshire, 24, 37, 38, 45 New Jersey, 29, 41, 49 New York, 21, 24, 29, 30, 33, 36, 37, 38, 39, 41, 44, 45, 47, 49 nigra group, 4 nivicola, Allocapnia, 14, 17, 46, 49, 58, 71, 72, 73, 77, 84 nivicola, Perla, 49 North America, 79, 82 North Carolina, 24, 26, 27, 32, 41, 42, 46, 49 Northeastern Gateway, 76 North temperate organisms, 80 Nova Scotia, 24, 36, 37, 38, 45, 49 Occam’s razor, 71 Ocean paleotemperatures, 82 oenone group, 4 Ohio, 21, 24, 29, 30, 32, 33, 35, 41, 44, 47, 48, 49, 67, 75 chioensis, Allocapnia, 12, 17, 46-47, 58, 72, 73, 78, 82 Ohio River Valley, 76 Oklahoma, 21, 23, 29, 30, 41, 65 Ontario, 21, 24, 29, 33, 38, 41, 45 ozarkana, Allocapnia, 14, 15, 34-35, 56, 67, 78, 85 Ozark-Ouachita Area, 62, 66, 73, 76, 80, 88, 89 INDEX 165 Ozark-Ouachita Mountains, 65 Ozarks, 67, 70, 72, 81 Paracapnia, 4 pechumani, Allocapnia, 13, 18, 36-37, 56, 67, 68 peltoides, Allocapnia, 12, 18, 30, 64, 78, 85 Pennsylvania, 21, 24, 29, 30, 37, 41, 44, 45, 49 perplexa, Allocapnia, 11, 16, 44, 57, 70, 85 Phaeognathus hubrichti, 63 Plecoptera, 2 Pleistocene, 81, 84, 89 Pleistocene associations, 60 Pleistocene calendar, 83 Pleistocene events, 78 Pleistocene glaciations, 60 Phocene, 79, 80, 81, 84, 88, 89 polemistis, Allocapnia, 10, 19, 24-25, 54, 62, 78, 85 Post-Wisconsinan dispersals, 74 Post-Wisconsinan time, 62, 66, 71 Post-Woodfordian, 77; dispersals, 84 pygmaea, Allocapnia, 1, 15, 17, 38, 45-46, 47, 58, 71, 74, 78, 87; misidentification, 45, 46, 49 pygmaea group, 53; dispersal, 71; phy- logeny, 58; taxonomy, 44 pygmaea, Semblis, 45 Quebec, 21, 24, 29, 33, 36, 37, 38, 45, 49, 69 Rapid evolution, 68 Recent, 82 recta, Allocapnia, 10, 19, 23-24, 54, 62, 75, 76, 78, 82, 83, 85 recta, Capnella, 23 recta, forms of, 62, 63 recta group, 52; dispersal, 61; phylog- eny, 54; taxonomy, 22 Reptilia, 6 Rhede Island, 45, 49 Rhyacophila glaberrima group, 80 Rhyacophila stigmatica group, 80 rickeri, Allocapnia, 14, 16, 41-42, 46, 57, 70, 75, 76, 77, 85, 86, 87 rickerl group, 53; dispersal, 70; phylog- eny, 57; taxonomy, 40 Rocky Mountains, 80 Salamander, 63 166 WINTER STONEFLY GENUS Allocapnia sandersoni, Allocapnia, 14, 16, 40-41, 57, 70, 85 Sangamonian interglacial stage, 69, 84 Scorpionflies, 2 Sexes, key to, 10 smithi, Allocapnia, 14, 17, 47, 48-49, 58, 72,73 South Carolina, 24, 26, 32, 46 Speciation, glacial stages and, 82 Springtails, 2 stannardi, Allocapnia, 13, 16, 17, 42, 57, 70, 85 Stoneflies, winter, 2 Tachytely, 68 Taeniopterygidae, 2, 3 Takagripopteryx, 3 Temperate deciduous forest, 8, 88 tennessa, Allocapnia, 11, 15, 20-21, 54, 61, 85 Tennessee, 21, 24, 27, 28, 29, 30, 32, 35, 41, 42, 43, 44, 46, 49, 73 Terminology, 8 Texas, 22, 76 Time-change correlation, 77 torontoensis, Allocapnia, 45 Trichoptera, 80 Two-creekan substage, 85 unzickeri, Allocapnia, 12, 18, 27-28, 64, 78, 85 Vagility, 59 Vermont, 24, 37, 45, 49 Vertebrates, 84 vidua group, 4, 5, 79, 80, 88 Virginia, 21, 24, 26, 29, 32, 37, 41, 44, 45, 46, 49 virginiana, Allocapnia, 10, 18, 25-26, 63, 64, 78 virginiana group, 53; dispersal, 63; tax- onomy, 25 vivipara, Allocapnia, 11, 15, 21-22, 51, 61, 75, 77, 87 vivipara, Capnella, 21 vivipara group, 52, 57; dispersal, 61; phylogeny, 54; taxonomy, 19-22 Warm interglacial periods, 89 warrenl, Allocapnia, 12, 27, 28, 64, 78, 85 Western North America, 80 West Virginia, 21, 24, 29, 30, 32, 35, 37, 39, 41, 44, 45, 49, 73 Wichita Mountains, 29, 65 Wings, 6, 52 Winter insects, 2 Wisconsin, 21, 29, 41, 45, 49, 71, 84, 85 Wisconsinan glacial stage, 66, 68, 77, 78, 82, 83, 87 Wisconsinan time, 62, 69, 70, 71 Woodfordian substage, 84 wrayl, Allocapnia, 15, 19, 32, 33, 55, 66 zekia, Allocapnia, 15, 32-33, 55, 66, 85 zola, Allocapnia, 138, 16, 43, 57, 70, 77 A Note on the Authors Herbert H. Ross, professor of entomology at the University of Georgia in Athens, formerly was professor of entomology at the University of Illinois and head of the Section of Faunistie Surveys and Assistant Chief of the Illinois Natural History Survey. William E. Ricker, Chief Scientist with the Fisheries Research Board of Canada in Nanaimo, British Columbia, is a distinguished biometri- cian, wildlife biologist, limnologist, and entomologist. ” ~ ” ePperen Pentre 3 ‘ v ‘ 7 ax asin t ' ‘ ‘ ) Het aT K Wat