NEW SPECIES OF WINTER STONEFLIES, GENUS ALLOCAPNIA (PLECOPTERA, CAPNIIDAE ) HERBERT H. ROSS and WILLIAM E. RICKER Illinois Natural History Survey, Urbana and Fisheries Research Board of Canada, Ottawa Printed from the Transactions of the Illinois State Academy of Science, Vol. 57, No. 2-1964 NEW SPECIES OF WINTER STONEFLIES, GENUS ALLOCAPNIA (PLECOPTERA, CAPNIIDAE) HERBERT H. ROSS and WILLIAM E. RICKER Illinois Natural History Survey, Urbana and Fisheries Research Board of Canada, Ottawa ABSTRACT.-Six new species of winter are deposited in the collection of the stoneflies from the temperate deciduous forest area of eastern North America Illinois Natural History Survey, belonging to the genus Allocapnia are with a duplicate set of paratypes de- described as follows (with the states posited in the Canadian National of occurrence indicated): A. pechumani ( N.Y.), A. tennessa (Tenn.), A. frisoni Museum. ( N.Y., Pa., W. Va.), A. peltoides ( Ark., Okla.), A. mohri (Okla.), and A. ohio- SYSTEMATIC DESCRIPTIONS ensis (Ind., Ky., Ohio). Diagnostic characters of the male genitalia are il- The following new species of Allo- lustrated for each species. capnia are small, dark members of One of the most intriguing genera the family Capniidae remarkably of insects in eastern North America similar in superficial appearance and is the stonefly genus Allocapnia. The general characteristics to species al- aquatic nymphs mature in very late ready described. The diagnostic dif- autumn and early winter, and the ferences between these species are adults emerge, mate, and lay their found in the shape of a few sclerites eggs from late November to late and processes at the terminal end of March, sometimes being active into the body, associated with genitalic early April in the northern part of structures. Information concerning their range. The genus is known only related species may be found in the from the area occupied by the tem- detailed studies of Prison (1935, perate deciduous forest and its north- 1942), Hanson (1942), and Ricker ern ecotone area with the boreal (1952). coniferous forest. Allocapnia pechum.ani, new species Because of the restricted ranges of Male.—Length 5 mm. Color dark certain species in this genus, we brown to blackish, the cerci and Venter think that these little stoneflies con- light brown, the wing veins medium tribute valuable information to an brown and the membrane slightly smoky. General structure typical for understanding of faunal movements genus. Wings reaching only to fourth and dispersals associated with the tergite. Genitalia typical of the A. glacial events of the Pleistocene. In forbesi group, Figure 1 A, B, C. Process of seventh tergite high, conical from the accumulation of material further- lateral view, its apex cleft to form ing these studies, several species new distinct lateral lobes, Figure 1 B. Proc- ess of eighth tergite high, its apex to science have been discovered, and cleft to form a pair of wide lobes, Fig- six of them are described in this ure 1 C. Upper supra-anal process with paper. short, sagittate apical segment. Female.—Length of head and body Unless otherwise specified, the 6 mm. Color and general structure sim- types of all species described herein ilar to male. Wings extending slightly [ 88 ] Winter Stone flies 89 upper supra-anal process PECHUMANI B , - PECHUMANI //. C TENNESSA au • 110PainA pi"- PECHUMANI MOHR! 11r11.1 1111 FRISONI prird(ii OHIOENSIS PELTOIDES FIGURE 1.—Male genitalic structures of Anocapnia species. A, D, E, F, lateral aspect; B, seventh tergite, posterior aspect; C, G, H, eighth tergite, posterior as- pect; I, tip of lower supra-anal process, dorsal aspect. 90 Transactions Illinois Academy of Science beyond the tip of the abdomen. Genital Allocapnia tennessa, new species segments indistinguishable from those of A. maria Hanson (Ricker, 1952, Fig- Male.-Length, color, and general ure 116). structure similar to the preceding. Holotype male, allotype female, and Wings absent. Genitalia, Figure 1 D, 11 male and female paratypes.-Stark- having upper supra-anal process short, ville, Herkimer County, New York, its apical segment as long as basal Otsquago Creek, March 27, 1960, K. R. segment. Seventh tergite without a Chadwick. Paratypes - NEW YORK: raised, sclerous process. Process of Albany County, Trout Pond Creek, near eighth tergite moderately low, its lat- Hicks Pond, Rensselaerville, April 6, eral aspect pointed at tip and forming 1963, L. L. Pechuman, two males; a sharp angle with the posterior por- Cayuga County, Paines Creek at Route tion of the segment, its posterior aspect 90, Aurora, March 23, 1963, L. L. Pechu- evenly arcuate, almost exactly as in man, twelve males and four females; Figure 1 G. Greene County, tributary of West Kill, Female.-Length 7 mm, color and near Sprucetown March 31, 1963, L. W. general structure similar to male. All, one female; Schenectady County, Wings of allotype reaching almost to small stream three miles south of tip of abdomen, in paratypes varying junction of Route 30 and Route 159, from short (reaching only to fourth March 19, 1957, P. H. Freytag, four tergite) to long (extending slightly be- males; Schuyler County, tributary of yond tip of abdomen). Seventh and Taughannock Creek, one-tenth mile eighth sternites with their mesal area south of Mecklenburg, March 5, 1963, fused; eighth, ninth, and tenth tergites L. L. Pechuman, nine males and eight completely and heavily sclerotized. females; Tompkins County, Willow Holotype male, allotype female, and Creek, corner of Kraft and DuBois 4 male and female paratypes.-Three Roads, Ithaca, March 24, 1963, L. W. miles north of Fayetteville, Tennessee, All, three males and one female; Tomp- January 27, 1958, H. H. and J. A. Ross. kins County, Willow Creek waterfalls, Paratypes-TENNESSEE: Triune, Jan- five and seven-tenths miles north of uary 27, 1958, H. H. and J. A. Ross, Ithaca, Route 89, March 24, 1963, L. W. eight males; two miles south of Shelby- All, three males and one female; Tomp- ville, January 27, 1958, H. H. and J. A. kins County, Danby Creek, junction of Ross, two females; five miles northwest Route 96 Band Van Etten Road, Danby, of Shelbyville, on U.S. Alternate 41, March 29, 1963, L. W. All, 12 males and January 26, 1958, H. H. and J. A. Ross, 20 females; Tompkins County, Butter- two males and one female; Rutherford milk Falls State Park, Ithaca, March County, Overall Creek, near south of 16, 1963, L. L. Pechuman, eight males; Allisona, January 13, 1963, H. H. and Esperance, April 11, 1937, H. H. Ross, J. A. Ross, two females; Marshall Coun- one male; Fredonia, April 13, 1937, ty, East Rock Creek, five miles north of H. H. Ross, six males; Ithaca, Beebe Lewisburg, January 13, 1963, H. H. and Lake, March 11, 1959, S. E. Neff, one J. A. Ross, one male; Maury County, male; Ithaca, Beebe Lake, March 20, ten miles west of Columbia, February 1959, B. Lund, one female; Starkville, 11, 1962, Ross and Ross, one female; Otsquago Creek, March 27, 1960, K. R. Maury County, Duck River, February Chadwick, ten females and three males. 11, 1962, Ross and Ross, four males and Deposited in the collections of the Illi- two females. nois Natural History Survey, the Ca- This species is a close relative only nadian National Museum, Cornell Uni- of A. vivipara Claassen, differing versity, and the collection of P. H. Freytag, Columbus, Ohio. from that species in the short basal This species is most closely related segment of the upper supra-anal to A. forbesi Frison but differs in process, and the less extensive fusion having the process of the seventh of the female seventh and eighth tergite cleft and occupying the mid- sterna. dle or the front half of the tergite. From A. maria Hanson this species Allocapnia frisoni, new species differs in the wide lobes of the proc- Male.-Length, color and general structure similar to the preceding. ess of the eighth tergite. Wings reaching sixth segment. Seventh Winter Stone flies 91 tergite having no sclerous process. versity, and the collection of P. H. Eighth tergite, Figure 1 E, rising grad- Freytag, Columbus, Ohio. ually posteriorly, the lateral aspect of The small, setose processes below its dorsal process appearing as a fiat sloping area that is somewhat shield- the process of the eighth tergite in- shaped from dorsal view; below the dicate that of the described species tip of the process there is on each side of Allocapnia this species is most a short, small, prominent projection bearing fine hairs. Both arms of supra- closely related to A. granulata. From anal process short, the upper one having this species A. frisoni differs in the the apical and basal segments about equal in length. flat and somewhat shield-shaped area Female.-Length 6 mm, color and which represents the rugose dorsal general structure similar to male. process of the eighth tergite of the Wings extending beyond apex of abdo- men. Seventh and eighth sternites not male. fused, the mesal area of the posterior Allocapnia peltoides, margin of the eighth sternite having new species a wedge-shaped shining area, indistin- Male.-Distinguished from the pre- guishable at present from illustrations ceding species only in characters of of A. granulata (Claassen) (Frison, the genital segments, as follows, Figure 1935, Fig. 220). 1 F: dorsal process of eighth tergite Holotype male, allotype female, and larger, its lateral aspect with the tips 7 male and female paratypes.-Evans- of the rugose area more anterior to the vine, West Virginia, March 16, 1945, small haired processes than in A. fri- Frison et al. Paratypes.-NEW YORK: soni, the dorsal aspect forming a larger Cayuga County, Little Creek at Route shield; dorsal aspect of the upper supra- 90, Aurora, March 23, 1963, L.