Bulletin STATE OF ILLINOIS HENRY HORNER, Governor DEPARTMENT OF REGISTRATION AND EDUCATION DIVISION OE THE NATURAL HISTORY SURVEY THEODORE H. PRISON, Chief Volume 21 BULLETIN Article 4 Descriptions of Nearctic Caddis Flies (Trichoptera) With Special Reference to the Illinois Species HERBERT H. ROSS PRINTED BY AUTHORITY OF THE STATE OF ILLINOIS URBANA, ILLINOIS March 1938 STATE OF ILLINOIS Henry Horner, Governor DEPARTMENT OF REGISTRATION AND EDUCATION John J. Hallihan, Director BOARD OK NATURAL RESOURCES AND CONSERVATION John J. Hallihan, Chairman William Trelease, D.Sc, LL.D., Biology Henry C. Cowles, Ph.D., D.Sc, Forestry L. R. HowsoN, B.S.C.E., C.E., Engineering Edson C. Bastin, Ph.D., Geology Arthur Cutts Willard, D.Eng., LL.D., President of the University of Illinois William A. Noyes, Ph.D., LL.D., Chem.D., D.Sc, Chemistry NATURAL HISTORY SURVEY DIVISION URBANA, ILLINOIS Scientific and Technical Staff Theodore H. Frison, Ph.D., Chief SECTION OF ECONOMIC ENTOMOLOGY W. P. Flint, B.S., Chief Entomologist C. C. CoMPTON, M.S., Associate Ento- mologist M. D. Farrar, Ph.D., Research Ento- mologist J. H. Bigger, B.S., Associate Ento- mologist S. C. Chandler, B.S., Southern Field Entomologist L. H. Shropshire, M.S., Northern Field Entomologist W. E. McCaulev, M.S., Assistant Entomologist C. W. Kearns, Ph.D., Research Fellow in Entomology DwiGHT Powell, M.S., Research Fellow in Entomology Arthur E. Ritcher, B.A., Research Fellow in Entomology SECTION OF INSECT SURVEY H. H. Ross, Ph.D., Systematic Ento- mologist Carl O. Mohr, Ph.D., Associate Ento- mologist, Artist B. D. Burks, Ph.D., Assistant Ento- mologist This paper i SECTION OF AQUATIC BIOLOGY David H. Thompson, Ph.D., Zoologist George W. Bennett, M.A., Limnologisl D. F. Hansen, M.A., Assistant Zoologist SECTION OF GAME RESEARCH AND MANAGEMENT R. E. Yeatter, Ph.D., Game Specialist W. H. Leigh, M.A., Assistant Zoologist C. T. Black, M.S., Research Fellow SECTION OF WILDLIFE EXPERIMENTAL AREAS A. S. Hawkins, M.S., Game Technician F. C. Bellrose, B.S., Assistant Game Technician C. H. Muller, Ph.D., Plant Ecologist SECTION OF APPLIED BOTANY AND PLANT PATHOLOGY L. R. Tehon, Ph.D., Botanist J. C. Carter, Ph.D., Assistant Botanist G. H. Boewe, M.S., Field Botanist SECTION OF FORESTRY James E. Davis, M.F., Extension For- ester SECTION OF PUBLICATIONS James S. Avars, B.S., Editor m the Section of Insect Survey (44257—1300—12-37) FOREWORD This paper, describing new species of caddis flies from Illinois and other localities in North America, is the initial report on a project of the Illinois Natural History Survey pertaining to these aquatic in- sects. A complete report treating of the Illinois fauna is planned tor later publication. This latter, more comprehensive faunistic study will be fashioned after some recent Survey reports on insect groups and will include keys to the adults and larvae, illustrations of the diagnostic characters, and data on the biology and distribution of these insects occuring in Illinois. The role of these insects in the economy of our lakes and streams makes their study of special interest. This investigation was started as a major enterprise of the Insect Survey Section during the summer of 1931. Dr. Cornelius Betten of Cornell University was employed by the Illinois Natural History Sur- vey during the summer of that year to initiate the extensive field work and acquaint the systematic entomological staff of the survey with the characters used in the classification of caddis flies and, in so far as possible, with the identity of the various species inhabiting the waters of our state. Since 1931, Dr. H. H. Ross, Systematic Entomologist of the Illinois Natural History Survey, has been responsible for the con- tinuation of this project. In addition to the great assistance received from Dr. Betten, our studies have profited greatly by Dr. Ross' study of the Hagen and Banks types in the Museum of Comparative Zoology, Cambridge, Massachusetts, kindly made available for detailed study and designation of lectotypic specimens by Dr. Nathan Banks. As these studies progressed, it became apparent that a study of the entire North American fauna would be necessary to identify properly the Illinois species. Therefore, specimens were assembled from localities representing as many parts of the continent as possible. Some of this material was obtained by Illinois Natural History Survey field trips, whereas other material was submitted for study by outside individuals and institutions. When all of this material was finally determined, it was found that a large proportion of it represented new species. It now seems advisable to describe these forms new to science so that the names may be known to others and made available tor use in future publications of the Survey. T. H. FRISON Kankakee River near Momence, Illinois Many of Illinois' rarest and most interesting species of caddis flies have been found in this clear, fast-flowing stream. ILLINOIS NATURAL HISTORY SURVEY BULLETIN VOL. 21, ART. 4 MARCH 1938 Descriptions of Nearctic Caddis Flies (Trichoptera) With Special Reference to the Illinois Species HERBERT H. ROSS DESCRIPTIONS of the new species of caddis flies (Trichoptera) treated in this paper are based for the most part upon specimens collected by various members of the Illinois Natural History Survey. They are based in part, also, upon other collec- tions sent to the Survey by the follow- ing members of other institutions: G. F. Knowlton, Utah State Agricultural College, Logan, Utah; J. W. Leonard, Institute of Fisheries Research, Ann Arbor, Michigan; D. C. Mote and R. E. Dimick, Oregon State Agricultural Col- lege, Corvallis, Oregon; R. W. Kaiser, Oklahoma Agricultural College, Still- water, Oklahoma; and various staff members ot the LTniversity of Wisconsin, Madison, Wisconsin. I wish to thank these individuals and others who have been of assistance to me at various times for their welcome cooperation. In several cases, notably in Hydro- psyche, the differences used to separate the adults into species will appear slight. Collections of thousands ot specimens and the association ot larvae with adults, however, have shown that these small differences are (1) constant and visible through the large series I have studied, (2) correlated with marked differences in the larvae, (3) correlated with distinct ecological habits and dis- tribution patterns and (4) trequently associated with distinct differences in the color pattern of the males. Many ot the species herein described have been reared. The descriptions ot the larvae and pupae will not be pre- sented now but will be treated in the torthcoming report on the caddis flies ot Illinois. These descriptions will be much more valuable when taken up in conjunction with a synopsis ot the entire Illinois group. Most of the drawings have been made by Dr. C. O. Mohr, of the Illinois Natural History Survey, to whom I wish to express my deep gratitude. The drawings ot genitalia in all cases have been made from genital capsules cleared in caustic potash (KOH) solu- tion, washed in distilled water and mounted in glycerin. Many structures necessary for accurate identification cannot be seen clearly unless the speci- men is treated in this manner. Except for the few paratypes other- wise noted, the types ot the species described in this paper are deposited in the collection of the Illinois Natural History Survey. The structures hitherto called preanal appendages, socii, anal appendages, etc., appear to be indubitably associated with the lateral margins of the tenth tergite. For this reason they are con- sidered the true cerci. In many of the more primitive genera there is no doubt that these cerci are homologous to the same structure in Hymenoptera, Me- coptera and other orders. The general order of families and genera is, with few exceptions, that used in Dr. Cornelius Betten's Caddis Flies of Neiv York Slate. Wherever reference 102 ILLINOIS NATURAL HISTORY SURVEY BULLETIN Vol. 21, Art. 4 is made in the text to "Betten (1934)" this book is the one indicated.' Family RHYACOPHILIDAE Rhyacophila fenestra new species This handsome species, fig. 1, is re- lated to members of the Carolina group but differs from previously described forms in the digitate spurs on the lateral arms ot the oedagus as well as in other points of the genitalia. Male.—Length 11 mm. Head straw color with a quadrangular dark brown spot between the ocelli; antennae and palpi dark brown; eyes black. Thorax brown with the venter, prothorax and lateral sutures yellowish. Abdomen straw color, the dorsum with a purplish cast. Legs straw color with the tarsi suffused with brown. Front wings gray with white markings in the membrane, each marking supplemented with a Oedagus ^ (J Genitalia Fig. 2. — Rhyacophila fenestra patch of silvery pubescence on the dorsal side; these light markings are all situated between the darker veins and are so arranged that they form more or less diagonal bands of spots across the wing. Hind wings uniform bluish- gray. The various warts, raised areas and the veins on the wings are provided with rows or clusters of long setae which are either brown, golden or a mixture of these two colors. The blue-gray patches of the front wings are clothed with minute, dark setae matching the color of the wing membrane. The pubescence of the legs is straw color. General structure typical for genus. Tibiae with small, straw colored spines in addition to the usual number of very long ones. Front wing with fork of R2+3 distinctly beyond fork of R4+S; Mi+2 branching very close to margin; M3+4 branching midway between 7n-cu and margin of wing. Seventh sternite with a small, pointed mesal projection. Genitalia as in fig. 2. Claspers rel- atively short and broad, the dorsal margin of the apical segment subequal to the dorsal margin of the basal seg- Fig. 1. — Rhyacophila fenestra, adult 9 York State Mu Bulletin 292. December. March 1938 ROSS: NEARCTIC CADDIS FLIES 103 >^;i^s5^ Fig. 3. — Rhyacophila fenestra, larva ment; the apical segment incised for one-third its lateral and one-tourth its mesal length; both lobes straight and rounded, the dorsal one small and the ventral one large. At the base of the segment there is a mesal incurving lobe; most of the apical segment and this lobe are covered with short, dark setae. Tenth tergite narrow, the dorsal lobe cleft down the meson for more than one- half its length; the lateral lobes so pro- duced have convex dorsal margins with a rather short, sharp apical point; below these the segment is produced into two closely appressed concave plates which articulate with the dorsal band of the oedagus. Oedagus consisting of a basal bandlike structure that articulates with the tenth segment and an apical cluster of structures at the end of a membranous tube. This cluster is composed of (1) a semimembranous pair of arms arising at its base, these arms enlarged at the apex and bearing usually five large, incurved spines, each surrounded by small spines; (2) a dorsal, sclerotized median process which is thin and blade- like from the dorsal view and from lateral view is divided into two sinuate rods; and (3) a mesal structure that has a vertical membranous connection with a pair of fanlike ventral lobes which are thin, colorless, only semisclerotized and together are slightly concave on the meson. Fem.'^le.—Length 12 mm. Color and general structure exactly the same as for male. Sixth sternite with a narrow process on the meson. Eighth segment tubular, the dorsum carinate, the apical opening circular except for the emargi- nation caused by the dorsal carina. Holotype, male.—Herod, Illinois: May 12, 19.56, reared from Gibbons Creek, Ross & Mohr. Allotype, female.—Same data as for holo- type. Paratypes.—Illinois.—Herod: May 29, 1935, Ross &' Mohr, IcT; pupae collected May 5, Ross & Mohr, adults emerged at Urbana, May 7-12, 19.?6, 40^, 19; pupae collected May 12, Mohr & Burks, adults emerged at Urbana, May 14-June 6, 1936, 18c?', 179; pupae col- lected May 13, Prison & Ross, adults emerged at Urbana, May 17-24, 1937, lOd', 119. The larvae, fig. 3, are common in the rocky streams of the Ozark region in southern Illinois. Rhyacophila iranda new species This species most closely approaches MJixa Milne but differs radically in the elongate apical portion of the oedagus, fig. 4. Male.—Length 9 mm. Head and thorax black; the setiferous warts and antennae dark brown. Abdomen with Rhyacophila iranda 104 ILLINOIS NATURAL HISTORY SURVEY BULLETIN Vo\. 21, Art. 4 venter straw color and dorsum purplish. Legs with coxae and femora dark brown; remaining parts yellowish-brown. Wings dark brown with light patches in the membrane at the end of each apical cell and in the subcostal, cubital and anal cells; the pubescence dark brown except over the light areas, where it is almost white. General structure typical for genus. Genitalia as in fig. 4. Ninth segment with ventral portion narrower than dorsal. Clasper with basal segment about as long as depth of ninth segment, its dorsal and ventral margins slightly convex; the apical segment is slightly more than twice as long ventrally as dorsally, the apical margin scooped out and evenly concave, the dorsal angle slightly but sharply produced. Tenth tergite short, the dorsal angle produced into a pair of short points, the ventral angle produced into a pair of truncate lateral areas; most of the surface covered with sparse setae. Apical portion of oedagus with a pair of narrow lateral processes which taper to a thin curved apex, this extreme apical portion with a row of fine setae on the mesal margin; the mesal portion sclerotized, divided into a thin ventral process and a wide, somewhat spatulate, dorsal process. Holotype, male.—Mount Baker, Washing- ton: July 21, 1936, along Razorhone Creek, H. H. Ross. Rhyacophila manistee new species Belonging to the same small group as minora Banks, this species differs from it in the narrower tenth tergite and in the arrangement of the dorsal setae at the apex of the oedagus in two regular, parenthesislike bands, fig. 5. Male.—Length 9 mm. Color dark brown, the legs below coxae yellowish brown, the wings with membrane lighter than the venation, with slightly lighter spots at the ends of the apical cells; most of setae dark brown, intermixed with patches of golden setae. General structure typical for genus. Genitalia as in fig. 5. Tenth tergite, seen from above, almost twice as long as wide, the apex divided into two short, somewhat pointed lobes; laterally tergite is produced into a postero-ventral lobe with the apex pointed. Claspers with api- cal segment slightly shorter than basal one; basal segment almost twice as long as wide, the ventral margin straight; apical segment of ventral margin straight at base and upturned at apex; dorsal margin sinuate, so that the clasper is rounded off to a short apical lobe. Oedagus composed of two distinct parts: (1) a short compact basal portion which is sclerotized and has one ventral and three short, apical dorsal projec- tions and (2) a membranous extensile tube at the apex of which is situated a semisclerotized ovate structure which is hollowed out dorsally and has a con- spicuous band of small, black setae bordering margin of depression. Female.—Length 10 mm. Color and general structure same as for male. Genitalia very simple; eighth segment cf Genitalia Fig. 5. — Rhyacophila manistee tubular, tapering evenly from base to apex; the remaining segments of the ab- domen extensile, tubular and sub- membranous. Holotype, male.—Grayling, Michigan: May 21, 1936, along Manistee River near town, Prison & Ross. Allotype, female.—Same data as for holo- type. Paratypes.—Michigan.—Grayling: Same data as for holotvpe and allotype, 74 cf, 569. Lovells: May 22, '1936, along Au Sable River, Prison & Ross, 3(^. Rhyacophila melita new species This is distinct from all other North American species not only in the poorly set off and ovate terminal segment of March 1938 ROSS: NEARCTIC CADDIS FLIES 105 the clasper but also in the oedagus with its short, heavy, five-tined process, shown in fig. 6. Male.—Length 11.5 mm. Head dark brown with setiferous warts and anten- nae light brown. Remainder of body c? Genitalia Fig. 6. - Rhyacophila ynelita dark brown, with the legs and venter of the abdomen straw color. Wings uni- formly brown, the veins and stigmal region darker. General structure same as for genus, the diagnostic differences being almost entirely in the genitalia. Genitalia as in fig. 6. Seventh sternite with the small, triangular mesa! projection just above apex. Ninth segment cylindrical, onK- slightly longer dorsally than ventrally. Claspers only one-tenth longer than depth of ninth segment; the basal seg- ment has the ventral margin slighth' more than twice as long as the dorsal margin, the two being parallel; the apical segment, viewed lateralh', appears egg shaped, the dorsal side longer than the ventral side, the basal suture in- distinct dorsally, the inner margin with the dorso-basal region thickly set with long, stout setae. Tenth tergite, viewed laterally, appears short and beaklike; the dorsal aspect is divided into two halves, each one tapering toward apex and produced near meson into a short, pointed projection; the entire surface is sparsely set with setae. Oedagus as illustrated, the ventral process con- sisting of a narrow mesal style with a pair of semimembranous flaps at base; the dorsal portion is a heavily sclerotized structure with a single mesal spine at base and with the apex divided into a pair of bifid processes. Holotype, male.—Crawford County, Miclii- yan: June 16, 1935, north branch ot Au Sable River", J. \V. Leonard. Rhyacophila perda new species This species closely resembles monlana Carpenter and lobifera Betten, but differs from both in the dorsal prolonga- tion of the ninth segment which con- sequently overhangs the basal segment of the clasper. Male.—Length 13 mm. Head with lower portion yellowish brown, dorsal portion black with setiferous warts brown, antennae brown with a tawny ring at the base of each segment. Thorax light brown with the scutal lobes darker in the middle. Abdomen yellowish brown, the dorsum with a purplish tinge. Legs entirely yellowish brown. Wings completely infuscate with pur- plish brown, the veins darker; the mem- brane around the edge of the wing and in the radial area has small pale areas which do not contrast much with the darker part of the wing. General characteristics same as for genus. Front wing with fork of Ri+.i slightly before fork of R4+S. Genitalia as in fig. 7. Ninth segment with the dorsal portion twice as long as the ven- tral half and forming a quadrate angle into which fits the basal segment of the clasper. Clasper (lateral view) with basal half slightly longer than its width at apex; both upper and lower margins concave. Apical segment with its greatest diagonal length almost equal to basal segment and with a dorso- apical incision which forms a long, narrow dorsal lobe and a wide, truncate ventral lobe iuttina: out considerablv Genitalia Fig. 7. Rhyacuphila perdu 106 ILLINOIS NATURAL HISTORY SURVEY BULLETIN Vol. 21, Art. 4 beyond the dorsal lobe; the entire lateral face sunken except for the dorsal, basal and ventral margins. Tenth tergite fitting beneath meso-dorsal pro- jection of ninth; it is a relatively small, padlike area, appearing somewhat heart- shaped when viewed from above and as a plate when seen from the side. Oeda- gus has apical portion composed of two main parts: (1) a pair of slender lateral appendages set with small setae at apex and (2) a mesal sclerotized process which bears approximately the same parts as illustrated for fenestra but which have become so completely fused that they appear as a single structure. Holotype, male.—Mount Baker, Washing- ton: July 21, 1936, along Razorhone Creek, H. H. Ross. Agapetus artesus new species Practically identical with minutus and ////;// in size and general characteristics, this species differs in the short tenth tergite, particularly the vasiform side Fig. 8. — Agapetus artesus pieces or lateral pieces which have no spines on their distal margin. Male.—Length 5 mm. Color identi- cal with illini (see below), the body brown and the legs a lighter shade. General characteristics, such as spurs, antennae, ocelli and wings, typical of genus. The abdomen has the usual ovate organ on the fifth sternite and the long tapering process on the sixth. Genitalia as in fig. 8. Claspers short and deep; seen from the ventral aspect they appear to have a wide base and abruptly narrowed apex, the apical half having a pair of dark, sclerotized points, the larger on the ventral margin, the smaller near the dorsal margin, the two connected by a sclerotized ridge. Tenth tergite composed of two vasi- form lateral plates markedly narrowed and pointed at apex, connected by mem- branous folds. Cerci narrow at base, broader and almost truncate at apex; slightly more than one-third the length of the claspers, pointed latero-caudad and with a cluster of long setae on their lateral face. Oedagus simple with the apex slightly enlarged. Female.—Slightly larger than male, similar to it in color and general struc- ture. To date no distinguishing charac- ters have been found between this female and that of iUini. Holotype, male.—Greer Spring, Missouri: June 7, 1937, H. H. Ross. Allotype, female.—Same data as for holo- type. Paratypes.—Missouri.—Greer Spring: Mar. 28, 1937, T. H. Frison, 1 cf ; same data as for holotype, 1 cf, 3 9 Agapetus illini new species This species is indistinguishable from minutus except on the basis of genitalia. It is characterized by the longer tenth tergite with a smaller cluster of spines at its apex and a short apical spur on the clasper, fig. 9. Male.—Length 5 mm. Body dark brown, clothed with brown setae. Legs with basal half dark brown, apical half lighter, clothed with straw colored setae. Wings dark brown with slightly lighter setae. Spurs, antennae, ocelli and wings typical of genus. Fifth sternite with a bulbous organ and sixth with a stout mesal projection which is slightly longer than the segment itself. Genitalia as in fig. 9. Claspers nar- rowed toward apex, the upper margin convex; the mesal margin armed with two heavily sclerotized points, one on the dorsal and one on the ventral mar- gin, connected by a sclerotized ridge. Cerci curved outward and bearing on their lateral surface long setae. Tenth tergite composed of a dorsal membran- ous region and a pair of ventro-lateral sclerotized plates; these are truncate at the apex, which is armed with many spiny projections; the tenth tergite has at its base a pair of dorso-lateral sclerotized projections which can be readily seen only from the dorsal aspect. Female.—Slightly larger than male, March 1938 ROSS: NEARCTIC CADDIS FLIES 107 Fig. 9. — Agapetus illini similar to it in color and general struc- ture; middle tibia and basi-tarsus com- pressed. Filth, sixth and seventh stern- ites with a crescentic ridge running from the baso-lateral corner through the meso-apical region. Sixth sternite with a definite mesal projection at apex. Genitalia consists of a simple type of sclerotized tube with the apical seg- ments invaginated. Holytype, male.—Herod, Illinois: May 1, 19,^6, Ross cV- Mohr. Allotype, female.—Same data as tor holo- type. Paratypes.— Illinois.—Eichorn: May 11, 1935, C. O. Mohr, 4cf. Herod: Same data as for holotvpe, 24 d'; May 29, 1928, along Gibbons Creek, T. H. Prison, llcT; May 10, 1935, C. O. Mohr, 11 cf, 19: May 29, 1935, Ross & Mohr, 11 cf, 79; July 11, 1935, Ross & DeLong, 1 cT ; May 12, 1936, Mohr & Burks, 7cr, 39; May 13, 1937, Prison & Ross, 70cf , 7?. Agapetus medicus new species Another species indistinguishable from the miniitus group on the basis of general characteristics but radically different on the basis of genitalia, having the claspers long and truncate and the tenth tergite also long and truncate but lacking the apical dentation of minntiis and illini. Male.—Length 5 mm. Color and general structure as given for illini. .'Abdomen and genitalia as in fig. 10. Tenth tergite bilobed from base, each lateral lobe long and deep but narrow; truncate at the apex and bladelike, the ventral and apical margins without serrations or teeth, the upper margins concave and joined by membranous folds. Cerci slender and slightly sinuate; the apex narrowly rounded and the dor- sal half bearing a cluster of long, slender setae; the appendage attaining half the length of the lobes of the tenth tergite. Claspers, seen from the side, rectangu- lar, four times as long as high, the apex truncate except for a slight production near ventral margin and having a sclerotized ridge running across the mesal face at apex. Seen from above, the clasper is fairly uniform in thickness for about three-fifths its length, beyond which it tapers to a rounded tip rein- forced mesally by the apical sclerotized ridge. The oedagus is a simple tube, as in the other species of the group. d" Genitalia Fig. 10. Anapelui medicus Holotype, male.—McFadden Springs, .Ar- kansas: June 5, 1937, H. H. Ross. Paratypes.—.Arkansas.—Same data as for holotype, ic^ . Agapetus pinatus new species .Although this species is indistinguish- able from some previously described forms in color and general structure, the genitalia are markedly different. Male.—Length 5 mm. Body light brown, the antennae and legs even paler. Color and general characteristics same as for other members of the genus. Genitalia as in fig. 11. Claspers long and narrow. Seen from ventral view, they appear to have a rather long, rec- tangular basal portion tapering to a fairly sharp point; the sclerotized points on either side of the mesal ridge appear almost in line from this aspect. Tenth tergite with a dorsal semisclerotized portion composed of two flat plates obliquely truncate at apex anei almost 108 ILLINOIS NATURAL HISTORY SURVEY BULLETIN \'ol. 21, Art. 4 Fig. 11. — Agapetus pinaius touching on the meson; and with a ventral portion consisting of two long, sclerotized rods fused at the base with this dorsal portion and extending con- siderably beyond it, their apices abrupt- ly turned dorso-laterad and divided into two lobes visible from the dorsal aspect. The lateral one ot these apical lobes is divided into two small points, the mesal one clavate with several small, spiny processes. Cerci long, curved outward near apex and having a cluster of long setae along their dorso-lateral margin. The cerci and the ventral rods of the tenth tergite seem to be fused with each other and with the remainder of the tenth tergite at their base. Oedagus simple, composed of a basal tube in which articulates a slender sclerotized rod. Holotype, male.—Elkmont, Tennessee: June 12, 1935, H. H. Ross. Agapetus debilis new species This species is readily distinguished from other members of the group by the long and bidigitate claspers combined with the short tenth tergite. Male.—Length 6 mm. Body dark brown; the raised areas of the head and thorax, most of the anterior aspect of the head and legs below coxae straw color (except spurs, which are dark brown). Wings uniformly dark brown, the veins darker than the membrane. General characteristics as forjgenus except as follows: Front wings with radial crossvein oblique but with vein R2+3 hardly at all angled at that point; base without a large specialized area such as in Glossosoma. Legs with tibial spurs very long, all of them simple, their count being 2-4-4. Fifth sternite of abdomen without the usual compli- cated platelike appendage but with a raised area on each side connected by a raised line which runs transversely across the segment about one-third the distance from the apex. Sternites 6 and 7 with only small raised processes ending in a small point at apex. Genitalia as in fig. 12. Ninth segment cylindrical. Tenth tergite divided on meson for almost its entire length. Seen from lateral view, it appears wide at base, gradually tapering to a narrow, depressed, blunt apex; seen from above, the apices seem to diverge slightly from the main axis of the segment. Claspers very long, projecting three-fourths of Fig. 12. — JgnpclHS debilis their length beyond the remainder of the genitalia; the basal portion, or "handle" (comprising .6 of the entire length), is bowed, increasing in depth beyond the middle of the arc. Beyond this "handle" the clasper is divided into two long, fingerlike processes, both of them almost straight, the upper one slightly fusiform, the lower one tapering slightly from base to apex, each one surmounted by a group of setae, the setae on the dorsal process modified into flat spindles. The entire clasper is covered with scattered setae, those on the "handle" longest; it is concave mesally and turned in so that the ventral margin is considerably mesad of the March 1938 ROSS: NEARCTIC CADDIS FLIES 109 dorsal margin. Oedagus and its as- semblage very small, composed of short, needlelike processes articulating as a group with the tenth tergite andcTaspers. Holotype, male.—Logan Canvon, Utah: June 27, 1937, \V. P. Nye. This species brings up some interest- ing questions in relation to the genera ot the Glossosomatinae. It is placed here in Jgapetns but lacks the lateral plate on the fifth segment, which con- dition should exclude it from Agapetus. On the other hand, the straight tibial spur excludes it from Mystrophora anti the lack of a callosity on the front wing wing excludes it from Glossosonia. The venation, especially the oblique radial crossvein, is somewhat suggestive of Mystrophora. Here, then, we have a species set oft' from almost every known genus in the subfamily by the lack of a specialized development of the male. It may well be that a new genus should be erected for this. At present I am placing it in Agapetiis on the basis of general resemblance of genitalia. I be- lieve, however, that this species should be set oft" as a distinct subgenus. Per- haps, when the females are associated with more species in this group, we shall find it necessary to express many of the groups as subgenera and not genera. Anagapetus new subgenus Differs from Agapetiis s. st. in the fol- lowing characters in the male: Lateral platelike structures on the fifth abdomi- nal sternite represented only by small callous elevations which do not have an internal lamellate structure. No stern- ites with long, fingerlike mesal projec- tions. Front wing with the radial crossvein diagonal, joining R2+3 just basad of the fork of this vein. Other characters typical of the genotype. Genotype. — Agapetiis debilis new species (by original designation). Glossosoma excita nt^ species This species is distinguished from all others in the genus by the claspers, which are very wide at the base and taper to an apex that appears narrow and up- turned when viewed from the lateral cJ Genitalia OEDAGUS Fig. 13. ssosomii excUa aspect anel truncate when seen from the ventral. Male.—Length 7 mm. Color and general structure almost exactly as described (or veloiia (below), the diagnos- tic characters occurring chiefly in the genitalia. Genitalia as in fig. 13. Genital parts in repose shielded by lateral extensions of the ninth segment. Clasper very broad at base, ventral margin slightly sinuate, the dorsal margin arcuate, the clasper narrowing abruptly about two- thirds the distance from the base and turned up at its extreme apex; the ventral margin angled meso-dorsad so that the clasper has a wide mesal shelf with its meso-apical corner sharply angled; only the apex of the clasper has setae, these relatively short. Tenth tergite stocky, the dorsal margin de- clivous, the dorsal part of the apex forming a sharp, curved process, the portion beneath this rounded; from the extreme lateral portion of this region there arises a pair of cylindrical, tusk- shaped processes which bear no setae; mesad of these are a pair of fingerlike processes only half as long as the lateral ones and sparsely covered with setae. Oedagus long and simple, its apex nar- rowed and pointed, articulating by two ribbonlike structures which extend from the extreme base of the oedagus to near the lateral corner of the claspers. Holotype, male.— Pringle Falls, Oregon: May 26, 19JS, N. V. Canova. Glossosoma velona new species Although this species is closely re- lated to the parviiliiiii group, it is readily distinguished by the shorter cerci and claspers. no ILLINOIS NATURAL HISTORY SURVEY BULLETIN Vol. 21, Art. 4 abruptly angled at its apex, the apex arising free from the segment. Oedagus with a large mesal rod articulating with the tenth tergite at one end and with the remainder of the oedagus at the other; from near the base of this struc- ture arise two stout, sclerotized pro- cesses which appear almost fused at their base but are distinct and taper toward the slender and sharp apex. Female.—Length 7 mm. Similar in color and general characteristics to the male, differing chiefly in that the mid- tibiae and tarsi are enlarged and flatten- ed. Genitalia as in fig. 14. Sixth sternite with a raised meso-apical process. Eighth sternite produced at the base into a humplike keel, the apex flattened. Eighth tergite hoodlike, only slightly incised dorsally; remainder ofgenitalia a simple extrusible tube with thin, sclerotized supporting rods attached to base of clasper. Holotype, male.—Centralia, Washington: July 26, 1936, H. H. Ross. Allotype, female.—Same data as for holo- type. Paratypes.—Montana.—Ennis: July 8, 1936, along Madison River, H. H. Ross, TcT, 39. Oregon.—Arlington: July 29, 1936, along Columbia River, H. H. Ross, 19. Washington.—Same data as for holotype, 19. Glossosoma verdona new species The absence of hoodlike projections of the ninth segment groups this species with penitum Banks. It differs from penitum, however, in the ventral portion of the claspers and the subquadrate tenth tergite. Male.—Length 7.5 mm. Color and general characteristics exactly as de- scribed for velona. The distinguishing * CLASPER Fig. 14. — Glossosoma velona Male.—Length 6.5 mm. Head, in- cluding palpi and scape, dark brown, remainder of antennae straw color. Thorax and abdomen a slightly lighter shade of brown than the head. Legs straw color, the coxae and femora fre- quentlv suffused with brown. Wings brown,' the portion below the stigrna slightly darker than the rest, the veins in this region also darker than the others. General structure typical for genus as follows: Antennae slightly shorter than wing, broadest at base and tapering greatly to apex. Ocelli well separated from eye, postocellar region with two pairs of setiferous warts. Legs with a spur count of 2-4-4. The spurs on the front tibiae very short, on the middle and hind tibiae very long. Venation typical for genus. Sixth sternite with a broad, flat ligula arising on meson; seventh sternite with a small, stubby process on the meson. Genitalia as in fig. 14. The entire assemblage in repose enclosed by a hood- like extension of the ninth segment. Claspers with basal half broad, apical half suddenly narrowed, the apex slightly clavate and provided with a mesa! brush of stout setae. Tenth tergite held at right angles to longitudinal body axis, divided into two lobes; each of these has the apical portion sharply pointed and bears a lateral enlargement which is probably the cercus; this appendage has a large tooth at its base and is (J Genitalia Fig. 15. — Glossosoma verdona March 1938 ROSS: NEARCTIC CADDIS FLIES 111 characteristics occur only in the genital apparatus. Genitalia as in fig. 15. Claspers fairly long, basal half narrow, apical half con- siderably widened, the apical margin practically truncate, seen from either the lateral or ventral aspects; the apical half clothed with long setae and having a mesal lobe abundantly provided with setae. Tenth tergite almost as deep as long; the meso-apical corner is produced into a sharp, curved point; the ventral portion ends in a very broad, curved point and within this is a flaplike lobe; the entire structure is sparsely covered with setae, those on the apical margin being very Jong. Oedagus anchored at the base by two ribbonlike, sclerotized bands which are fashioned laterally near the base ot the claspers; the apical por- tion ot the oedagus is composed of two tapering, sclerotized rods; from the cen- tral portion of the oedagus arises an erect process with its apex enlarged into a knoblike structure which is densely covered with short, straight setae. Holotype, male.— Pinedale, Wyoming: July 6, 1936, along Green River north of town, H. H. Ross. Paratypes.—Utah.—Big Cottonwood Can- yon: April 24, 1937, G. K. Knowlton & F. C. Harmston, 5 d' . Wyoming.—Same data as for holotype, 2c?'. The five paratypes from Utah differ trom the others in being uniformly darker in color, and in having the dorso- mesal point of the tenth tergite of the male reduced or absent. The extreme similarity of all other points of the genitalia leaves no doubt, however, that the two series are the same species. Paragapetus celsus new species This species is most closely related to nearcticus Banks, but differs in lacking a long, palmate dorsal process on the tenth tergite. Male.—Length 4 mm. Color, in- cluding wings, legs and other ap- pendages, uniformly blackish brown. General structure: Antennae about 24-segmented, two-thirds length of lorewing. Maxillary palpi stocky, 5- segmented, first two segments short, third subequal in length to first two together, fourth slightly shorter than d* Genitalio DORSAL VIEW Fig. \6.- Pani^iipeliis celsus third, fifth slightly shorter than fourth, pointed at apex, fig. 16. Ocelli present, the median one situated between anten- nal sockets, the lateral pair midway between antennal sockets and posterior margin of head. Tibial spurs 2-4-4, none modified. Tarsal claws curved, fig. 16, all of them similar in shape. Wings with typical, simple, Rhy- acophilid venation; front wing with Rs and M having two symmetrical di- chotomies; Sci and basal abscissa of Sc2 variable. Abdomen has a sclerotized thickening just before apex on sternites 5-7; that on the seventh has a small, pointed thickening on meson. Genitalia as in fig. 16. Most of the parts seem fused at the base with the genital capsule. The lateral margin is prolonged dorso-apically into a forked 112 ILLINOIS NATURAL HISTORY SURVEY BULLETIN V'ol. 21, Art. 4 process; the upper prong ot the fork bears a row of stout, fairly longsetae on its dorsal margin, and a long, fingerlike process branches from its base, which may he seen dorsally; the lower branch is shorter, with only a few setae, and is situated almost directly beneath the upper. The ventral margin is produced apically into a pair of lateral lobes bearing scattered setae on their inner margin toward apex. Tenth tergite rounded and slightly upturned at apex. Oedagus submembranous, short and thick, with a sclerotized area on its ventral surface; the apex membranous. Female.—Length 4.5 mm. Similar in color and general structure to male. Abdomen simple in structure. Segments 1-7 normal, remainder retracted into abdomen to form an extensile tube. Bursa copulatrix as in fig. 16. Holotype, male.—Newfound Gap, North Carolina: lune 13, 1935, along Little Pigeon River, H."H. Ross. Allotype, female.—Same data as for holo- type. Paratypes. — North Carolina.—Same data as for holotype, 54 d', 109. Protoptila Banks On the basis of their small size and long fringe of hair on the anal margin of the wings, the small insects belonging to this genus would key out to the Hydroptilidae. Certain other charac- ters, however, such as the immature stages, lack of setation on the abdomen and the structure of the male and fe- male genitalia, present conclusive evi- dence that the genus belongs in the Glossosomatinae of the family Rhy- acophilidae. The adults of Protoptila may be keyed out from the Hydroptili- dae on the basis of always having ocelli which are distant from the eye. Protoptila jeanae new species This and the following three species differ from previously described mem- bers of the genus in lacking a produced, furcate apical sternite. Male.—Length 3.5 mm. Head and dorsum of body brown; antennae white with apical eight segments blackish brown; palpi, legs and venter whitish; tibial spurs brown; wings brown with a narrow, white transverse band two- thirds distance from base. General structure: Head robust and ovoid, with a pair of caudal warts, three prominent ocelli and a pair of larger warts between the lateral ocelli. Max- illary palpi five segmented; the first and second segments subequal and together subequal to the third; the third, fourth and fifth subequal; the entire palpus short and stocky. Antennae filiform, the two basal segments thicker than the rest. Tibial spurs 0-3-3. Abdomen membranous with only few setae except on genitalia. Genitalia as in fig. 17. Ninth tergite incised on margin, the lateral lobes pointed, fig. 17. Superior appendages with heavy setae along margins, apex surmounted by a rounded, sclerotized process. Claspers sinuate in lateral view, with no setae, the apex roughened and dark. Between these two pairs of appendages are exserted two narrow and pointed processes, and within the body can be seen an erect, somewhat hook-shaped appendage associated with the oedagus. Female—Size and general structure as in male. Apex of abdomen as in fig. 17, the ultimate segment rounded, the apex bearing a pair of fingerlike pro- cesses, the surface covered with fine setae pointing basad. Penultimate seg- ment broad and short, with two lateral slits, under which may be seen the broad, roughened bursa copulatrix. Holotype, male.—Sevierville, Tennessee: June 11, 1935, J. A. & H. H. Ross. Fig. 17. — Pioloplilii jennae March 1938 ROSS: NEARCTIC CADDIS FLIES 113 Allotype, female.—Same data as for holo- type. Paratypes.—Kentucky.—Livingston: June 16, 1935, along Rockcastle River, J. A. & H. H. Ross. 19. North Carolina.—Cherokee; June 14, 1935, J. A. & H. H. Ross, 21 cj', 39. Tennessee.—Same data as for holotvpe, 9cr, 39. Protoptila erotica new species In characters of tibial spurs and ven- ation, this species belongs to the ma- ciilata group but difters in lacking a , d" Tergites Fig. 18. — Proloplila erotica conspicuous and large ventral plate in the male. Male.—Length 3.0 mm. Color and general structure typical for genus. Middle and hind tibiae have four spurs of about equal length. Hind wings ex- cavated along the anterior margin be- yond the middle of the wing. Genitalia as in fig. 18. Tenth tergite divided into two lateral arms which together appear in somewhat the shape of a horseshoe. Ventral plate small, short and narrow, with a few apical setae. What appear to be the claspers are short, stubby processes angled at the apex and closely attached at the base to a plate bearing a paired mesal process which protrudes slightly beyond the claspers. Oedagus large, consisting of a large knoblike portion within the body cavity and an exterior portion. This consists of a central piece, which is angled and widened near its middle and tapers to its apex; arising from its base are two membranous arms, each bearing an elongate hook sheathed with membrane around the base. Female.—Similar in size, color and general structure to male. Holotype, male.—Parco, Wyoming: July 5, 1936, along North Platte River, H. H. & j'. A. Ross. Allotype, female.—Same data as for holo- type. Paratypes.—Illinois.—Momence: May 26, 1936, along Kankakee River, H. H. Ross, 124 d"; Aug. 21, 1936, Ross & Burks, 6cr. Wisconsin.—Chetek: June 5, 1936, Frison & Ro.ss, Icf, 3 9. Merrill: July 1 ,1933, along Wisconsin River, Frison & Mohr, 1 rf". Spooner: June 5, 1936, along Namekagon River, Frison & Ross, 1 cf. Wyoming.—Madison Junction, Yellowstone National Park: July 8, 1936, H. H. Ross, along Gibbon River, 5 cf. Parco: Same data as for holo- type, 8cr. Protoptila cantha new species Differs from other members of the genus in combining the characters of a single preapical spur on the hind tibiae with an incised hind wing, and in de- tails of the genitalia. Male.—Length 3.0 mm. Color and general structure t\'pical for genus. Head with only one pair of warts, situ- ated close to the posterior margin. Hind wing with anterior margin incised beyond middle, the wing therefore saberlike. Middle and hind tibiae with three short spurs, the single preapical Ventral Plate Fig. 19. — Proloplila canllui 114 ILLINOIS NATURAL HISTORY SURVEY BULLETIN \'ol. 21, Art. 4 spur being the same size as tiie two apical ones. Genitalia as in fig. 19. Tenth tergite horseshoelike, the apices appearing sharp and stout when seen from the side. Ventral plate bilobed in the center, the lateral angles having three small points. Claspers short, the apex ot each blunt. Oedagus contained in a hoodlike struc- ture which is somewhat triangular and extends the full width of the genital capsule. Oedagus a simple, heavy, sclerotized rod sharply bent at the base. Below the oedagus is a curved mesal process with a sclerotized dorsal portion and a membranous ventral border. Holotype, male.—Parco, Wyoming: Aug. 1, 1936, along North Piatt River, H. H. Ross. Paratypes.—Idaho.—Caldwell: July 30, 1936, H. H. Ross, along Boise River, Icf. Maryland.—Plummet's Island: June 24, 1902, H. S. Barber, 8cf . Wyoming.—Same data as for holotype, 1 cf. Protoptila thoracica new species Distinguished from other members of the genus by the enlarged scutal lobes and details of the genitalia. Male.—Length 3.0 mm. Color and -:=z:ZJ