Claassenia, Stark & Sivec, 2010

Stark, Bill P. & Sivec, Ignac, 2010, Systematic Notes On The Genus Claassenia Wu (Plecoptera: Perlidae), With Description Of A New Species, Illiesia 6 (24), pp. 303-314 : 312-313

Claassenia ChC

( Figs. 32-35 )

Material examined. China: [Sichuan Province], 50 miles NW Chengtu [= Chengdu], 1910, W.N. Ferguson, 1♂, 1♀ ( BMNH) .

Adult habitus. General color brown, head yellowish but with triangular dark brown ocellar spot, pronotum uniformly brown without distinctive rugosities. Legs uniformly brown.

Male. Macropterous, forewing length 29 mm. Hemitergal lobes slender, finger-like, but slightly swollen near mid length and positioned parallel to one another for most of length ( Fig. 32 ); inner margins of hemiterga in dorsal aspect bearing a prominent grouping of thick sensilla basiconica along most of length ( Fig. 33 ).Tergum 9 armed with a prominent circular patch of sensilla basiconica, tergum 8 without obvious sensilla basiconica patch.

Female. Macropterous, forewing length 40 mm. Subgenital plate produced as a small triangular projection bearing an apical, triangular notch ( Fig. 34 ). Intersegmental membrane between sterna 9-10 with a patch of microtrichia. Vagina broad near orifice and strongly narrowed in anterior third ( Fig. 35 ); spermatheca a large membranous structure on a long slender pedicel.

Egg. Spindle shaped with low button-like collar. No specimens available for scanning electron microscopy.

Larva. Unknown.

Comments. This is another intriguing, and apparently distinctive, species from Sichuan Province. The female subgenital plate is similar to, but much smaller than that of the Bhutanese species, C. drupka , described above, and the parallel position and prominent sensilla basiconica of the male hemiterga also appear to be distinctive. Unfortunately, several of the types of Claassenia species known from Sichuan province are unavailable to us.

Figures

Figs. 32-35. Claassenia ChC structures. 32. Male genitalia, dorsal. 33. Male hemitergum, dorsal. 34. Female abdominal sterna 8-9. 35. Vagina and spermatheca.