3541 Author Judson, Sarah W. Author Nelson, C. Riley text Zootaxa 2012 2012-11-06 3541 1 118 journal article 1175­5334 505937B0-9F57-4068-82E6-8553826DD5AA Isoperla asiatica Šámal, 1939 SYNONYMY Isoperla asiatica Šámal, 1939 TYPE LOCALITY: Mongolia , Sogino , Tula . DIAGNOSIS: The adult head is pale overall, with dark pigmentation surrounding the interocellar region which contains a pale oval spot ( Fig. 316 ). This pale central mark is broadly rounded in I. asiatica , whereas in I. potanini ( Fig. 345 ) and I. mongolica ( Fig. 336 ) it is pointed anteriorly and in othe r Isoperla it is more narrow. The mesoscutum has golden-yellow markings anteriorly ( Fig. 316 ), similar to I. kozlovi Zhiltzova, 1972 ( Fig. 326 ), I. mongolica , and K. nigricauda , but distinct from I. potanini which has uniformly dark mesoscutum ( Fig. 345 ). Males have poorly sclerotized paraprocts that are oriented dorsally and do not curve anteriorly over the 10th tergum. The vesicle on the 8th sternum is rounded and sessile ( Fig. 318 ), most similar to I. potanini which entirely lacks a lobe and is smooth along the segment 8 ( Fig. 347 ). Isoperla asiatica males can also be distinguished from I. potanini by cercal segments which posses only a single long hair per segment, in contrast to I. potanini cerci which have a whorl of long hairs on each segment. The female has a short, broadly rounded or truncate plate ( Fig. 319 ) which is indistinguishable from I. mongolica ( Fig. 339 ), but is distinct from the notched plate of I. potanini ( Fig. 348 ). Nymphs have a pale central ocellar mark ( Fig. 303 ) and color patterns reminiscent of the adult. DISTRIBUTION—Global: East Palearctic— Regional: AOB, IDB^, POB*- Aimag: AR^, BU^, DO*, KhE*, KhG^, SE, TO, UB, ZA^. DISCUSSION: In Mongolia, I. asiatica is most commonly found in large, low gradient streams. From our collections, this species appears to be restricted to the Selenge River basin ( Fig. 320 ), but is predicted to occur in the eastern Khentii region where it has been documented historically (Zwick and Surenkhorloo 2005).