Isoperla ornata Zhiltzova, 1988

Isoperla ornata Zhiltzova, 1988 View in CoL

Figs. 71–80 View FIGURES 71–80

Material examined. Russia, Far East, Primorsky Krai: 4♀, Komissarovka River, Khanka Lake basin, near Dvoryanka village , 23– 25.06.1994, coll. Bulavsky ; 1♀, Barabashevka River , light trap, 06.07.2021, coll. E. Gorovaya ; 4♂ 4♀, Komissarovka River, Komissarovo village , 28– 29.05.1998, coll. V. Teslenko ; 1♂ 1♀, Tigrovaya River, opposite Khmelnitskie Shcheki, Partizanskaya R. basin, 11 06.1998, coll. V. Teslenko ; 1♂ 1♀, Razdolnaya River near Fadeyevka village , 31.05.1998, coll. T. Vshivkova ; 1♂, 1♀, Razdolnaya River, near the border with China , coll. T. Vshivkova ; 4♂ 6♀, Shkotovka River , 25– 29.05.2015, reared, V. Teslenko .

Egg. The egg of I. ornata is described here for the first time. Egg pear-shaped, posterior ⅔ triangular in cross-section, anterior ⅓ square, with distinct cross-shaped ridges ( Figs. 71–72, 78–79 View FIGURES 71–80 ); anterior pole square, slightly concave ( Fig. 78 View FIGURES 71–80 ). Length 263‒269 µm, width 181‒192 µm (n=5), chorion thickness 3.1 µm. Collar well developed, elevated with irregular and raised longitudinal ridges; rim flanged, serrated, or wavy; collar base offset with pits ( Figs. 74–75 View FIGURES 71–80 ). Anchor mushroom-shaped, with small globular bodies concentrated into groups of 2–5 and located mainly in a peripheral area along the anchor edge, top deeply embedded and covered with single globular bodies; anchor covers the collar completely ( Fig. 73 View FIGURES 71–80 ). Hexagonal FCI’s ridges slightly raised and thickened, floors flat with numerous (about 16) punctations ( Fig. 80 View FIGURES 71–80 ); eclosion line absent. Micropyles small and weakly visible, arranged singularly on follicle cell ridges near the anterior ⅓ of the egg ( Fig. 77 View FIGURES 71–80 ). Orifices set in small, oval, cup-shaped depressions; sperm guides poorly visible ( Figs. 71–72, 77 View FIGURES 71–80 ).

Distribution. East Asian species with limited distribution in the south of the Russian Far East, including the Jewish Autonomous Region, Khabarovsk Krai, and Primorsky Krai.