Isoperla lunigera (Klapalek, 1923)

Judson, Sarah W. & Nelson, C. Riley, 2012, 3541, Zootaxa 3541, pp. 1-118 : 48

Isoperla lunigera (Klapalek, 1923)

SYNONYMY

Chloroperla lunigera Klapálek, 1923

Isoperla lunigera Claassen, 1940

TYPE LOCALITY: USSR: Irutsk.

DIAGNOSIS: The head mask of adults is distinctive, having an isolated, quadrate patch covering the interocellar area ( Fig. 331). No other pigmentation is present on the head with exception of the pedicel of the antennae. The pronotum has pale margins and a wide pale median stripe bordered by two dark sublateral stripes ( Fig. 331). The male has a distinctive large penial sclerite ( Fig. 333) that is symmetrical in the caudal view in contrast to I. altaica ( Fig. 313) and I. eximia ( Fig. 323) which both have a similarly shaped, but asymmetrical sclerite. The female subgenital plate is broadly joined at the base, with dark pigmentation along the anterior edge and a central bump that protrudes only slightly over segment 9 ( Fig. 334). Nymphs are superficially similar in coloration to I. altaica , with the majority of the head dark especially in the ocellar region and pale areas near the eyes and center of the clypeus ( Fig. 306). However, I. lunigera has fewer dark regions particularly on the thorax and is more pale overall.

DISTRIBUTION—Global: East Palearctic— Regional: AOB, IDB, POB*— Aimag: AR*, BU^, DO*, KhE*, KhG, SE, TO^, UB^, ZA*.

DISCUSSION: Specimens of this species were misidentified in historical collections as Isoperla flavescens (Zwick & Surenkhorloo 2005) and erroneously published as a new species record for Mongolia in Purevdorj et al. (2003). The yellow coloration, small size, and slenderness of this species can be easily confused with Chloroperlidae , specifically Haploperla lepnevae (Chloroperlidae) which has similar coloration, particularly the presence of an isolated dark mark on the head.