Arcynopteryx altaica, Teslenko, Valentina A., 2012

Teslenko, Valentina A., 2012, A taxonomic revision of the genus Arcynopteryx Klapálek, 1904 (Plecoptera, Perlodidae), Zootaxa 3329, pp. 1-18 : 8-11

Arcynopteryx polaris Klapálek, 1912 .

( Figs 22–29 )

Klapálek 1912: 20 ( Arcynopteryx dichroa var. polaris ); Zapekina-Dulkeit 1960: 667, 668, figs 6−10 ( Arcynopteryx altaica sp. nov.); Zhiltzova & Zapekina-Dulkeit, 1986: 182, figs 2, 3, 5, 6 ( Arcynopteryx altaica ); Zhiltzova 1995: 7 ( Arcynopteryx polaris Klapálek, 1912 = Arcynopteryx altaica Zapekina-Dulkeit, 1960 , syn. nov.); Teslenko & Zhiltzova 2009: 26, figs 126−128.

Diagnosis. Tergum 9 is rather smooth without notch posteriorly ( Fig. 23 ). A. polaris can be distinguished from other species by the simple shape of hemitergal lobe, which is elongated, flattened, directed medially. A knob is absent ( Fig. 25 ). Each lateral sclerotized band interiorly of the cowl of the epiproct is widened basally, with a triangular-rounded extension medially ( Fig. 24 ). The stylet of the epiproct resembles a long, fine bristle directed upward and backward; is arched in a loop with well sclerotized, triangular-shaped base, and is attached between triangular extensions of the lateral sclerotized bands at the bottom of the cowl ( Fig. 24 ). The aedeagus ( Fig. 23 ) is large, with pair of large lateral lobes dorsolaterally; one prolonged carrot-shaped lobe presents between lateral lobes and bears a small swollen knob dorsomedially; the membranous apex resembles a small hook. The carrot-shaped lobe is covered with fine erect clear spinules which are grouped below the small swollen knob laterally, except for a mesal membranous narrow band. Egg is smaller than other Arcynopteryx species. The sides of collar appear knitted; shoulder is not pronounced ( Figs 27 & 28 ). The chorion is covered with hexagonal FCI’s; flat floors contain 7−13 punctations the same depth as on the walls ( Fig. 29 ).

Adult habitus. The head ( Fig. 22 ) is wide, transverse, with M-shaped dark brown band between antennal bases, M-line is pale. In front of the M-line a distinct arrow-shaped brown spot projects onto the clypeus, the tentorial pits are brown, lateral margins of the clypeus are pale. The interocellar area exhibits a pale spot pointed anteriorly that does not reach the median ocellus and continues to the occiput medially. Pair of the tentorial pits in front of the lateral ocelli and pair of small oval patches laterally to lateral ocelli is pale. Behind each compound eye is a posterolateral spot with brown callosities ( Fig. 22 ). The antennae and palpi are brownish; the basal antennal segments are brown. The submental gills are rounded and short or very short. The pronotum is the same width as head width under compound eyes, brownish, quadrangular, with rounded angles, the lateral margins are straight; a median pale band occupies 1/5 of pronotal width, expanding posteriorly ( Fig. 22 ). The pronotal rugosities are dark brown, lateral fields are light brown. Meta- and mesonotum are brown with thin incomplete pale band medially. Arms of mesosternal ridge meet anterior corners of furcal pits. The abdomen is covered by colorless hairs, pronounced on the last abdominal terga posterolaterally. The anterior margin of femur is dark brown, the distal edge is pale; tibia is light brown with thin dark brown stripe basally. The cerci are longer than abdomen, with brownish hairs; the basal cercal segments are brown, segments in the middle of the cercal length are brown with narrow pale basal ring. The forewing is long, narrow, transparent, and sometimes clay-colored, with brown veins. The venation includes an irregular net near the apex, occasionally consisting of three rows of cells. The hind wing anal area is large, and A1 and A5 are forked. Brachypterous and long-winged specimens occurred together the same sampling site.

Male. Body length of full-winged male 11.2−15.2 mm, forewing 9.1−13.0 mm, wingspan 19.2–27.5 mm; forewing of male with shortened wings 2.5−6.0 mm, wingspan 6.6–13.5 mm. Abdominal tergum 9 is straight posteriorly, without notch (or with very shallow medial notch); two weak submedial swellings are present. These swellings are covered by small stout setae and long fine colorless hairs posteriolaterally ( Fig. 23 ). Sternum 9 is scoop-shaped, extended backward and curved upward, posterior margin is pale medially. Tergum 10 is pale, divided into two hemiterga. The hemitergal lobes in a dorsal view are simple, elongated, flattened and directed medially. The knobs are absent ( Figs 23 & 25 ). The posterior margins of the hemitergal lobes are smooth and pale, less sclerotized than anterior ones, mesal edges bluntly rounded ( Fig. 25 ). The cowl is membranous folded resembles a deep pouch between and under hemitergal lobes, and is attached around the base of epiproct and the internal basal anchor. The dorsolateral edges of the cowl are supported by flat and darkly sclerotized paragenital plates. In dorsal view, the arrow-like sclerites of the internal basal anchor are black, fragile, hidden under tergum 9, and reach the tergal margin anteriorly. In lateral view, the lever arm is stout, hemispherical, and hollowed ( Fig. 24 ). Two sclerotized lateral bands are fastened to the lever ventrally and support the cowl ventrolaterally. Each lateral sclerotized band is widened basally, has a triangular-rounded extension medially ( Fig. 24 ). The stylet of the epiproct resembles a long, fine bristle directed upward and backward. The stylet is arched in a loop, the basal plate of the loop is a triangular-shaped, well sclerotized, and attached between triangular extensions of the lateral sclerotized bands at the bottom of the cowl ( Fig. 24 ). In dorsal view, everted aedeagus ( Fig. 23 ) is large, membranous, wide medially, with pair of lateral rounded lobes at dorsolateral margins, lobes not be fully everted; one prolonged carrot-shaped lobe is between lateral lobes and bears a small swollen knob dorsomedially and ends by a small hook-shaped membranous apex. The carrot-shaped lobe is covered with fine, erect, clear spinules which are grouped below the small swollen knob laterally, except for a narrow mesal membranous band ( Fig. 23 ).

Female. Body length 11.8−18.5 mm, full-winged, length of forewing 12.8−16.5 mm, wingspan 27.1–33.9 mm; shortened wings, length of forewing 4.6−5.3 mm, wingspan 10.6–12.3 mm. Sternum 8 without spots anteriorly, the subgenital plate is large, relatively short, extends laterally from the sides of sternum 8, and does not exceed half of the length of the sternum 9 ( Fig. 26 ). The posterior margin of the subgenital plate is straight or exhibits a shallow notch that separates two triangular, short, sloped laterally, and rounded lobes. The subgenital plate is covered with small, colorless setae. Sternum 9 is pale medially, with two brown circular spots mesolaterally ( Fig. 26 ).

Egg is ovular ( Fig. 27 ) and circular in cross-section, smaller than other Arcynopteryx species, 395 x 293µm. Anchor mushroom-shaped does not cover the collar ( Fig. 27 ), the globular bodies are grouped closely to the margin of the anchor plate. The collar short, sides of collar appear knitted; shoulder is not pronounced ( Figs 27 & 28 ). The chorion is covered with hexagonal FCI’s ( Figs 27 & 29 ); the FCI walls are raised with thin, deep furrows; flat floors often contain 7-13 punctations, the depth of flat floor’s punctation is the same as the wall’s depth ( Fig. 29 ).

Row of micropyles is subequatorial; orifices small with indistinct lips, some set on very low micropylar mounds are surrounded by pentagon rosettes ( Fig. 29 ).

Material examined. Type, male, lectotype, male, Lena River, mouth, Bykov peninsula, 14.07.1902, coll. Brusneva, det. Klapálek. Paralectotypes: female, the same place, 12.07.1902; 2 males, 1 female, Priayanskaya tundra, 25− 26.06.1902, coll. Brusneva. Khabarovskiy Region, 12 males, 3 females, Uyka River, 0.5 km from Ayan Airport, 21- 26.07.1999, coll. T. Tiunova; 7 males, 6 females, Bulginka R., Okhota R. Basin, Bulgin settlement, 26.06.1999, coll. Т. Тiunova; 17 males, 7 females, the same place, 3.07.1999, coll. T. Tiunova; 5 males, 1 female, Petin stream, Nemptu R. Basin, Amur R. Basin, 21.06.1998, coll. V. Тeslenko; Chukotka peninsula, 11 males, 2 females, Nevedimka stream, Whalen settlement vicinity, 11.08.1973, coll. I. Chereshnev.

Distribution. A. polaris extends to Siberia (Altai and Sayan Mountains) the Russian Far East, including Wrangel Island, as well as in Mongolia, China ( Teslenko 2006), and Korea ( Zwick 2010).

Figures

FIGURES 22 – 26. Arcynopteryx polaris: 22. Head and pronotum of male. 23. Male abdominal tip with aedeagus, dorsal. 24. Cowl: sclerites of the internal basal anchor, lever arm, paragenital plate, hemitergal lobe, stylet and loop of the epiproct, and two lateral sclerotized bands, lateral. 25. Male left hemitergal lobe, dorsal. 26. Female abdominal tip, ventral. Scale (mm): 24, 25 = 1.0.

FIGURES 27 – 29. Arcynopteryx polaris, egg: 27. Habitus: anchor, chorion structure, lateral. 28. Collar and anchor, lateral. 29. Chorion structure, micropylar orifice, mound, and pentagon rosettes, dorsal view.