Claassenia drukpa, 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 : 303-305

Claassenia drukpa sp. n.

( Figs. 1-11 )

Material examined. Holotype ♂ and 2♂, 1♀ paratypes from Bhutan, Punakha, Dungkhar Rongchhu , 27° 29’ N, 89° 46’ E, 1370 m, 24 April 2006, H. Malicky ( PMSL).

Adult habitus. General color tan patterned with darker brown. Head with dark pigment in ocellar triangle invaded by pale pigment ( Fig. 1 ); lappets dark brown but most of head pale brown. Basal antennal segment brown, segments 2-3 dark brown and remainder of flagellum pale brown. Pronotum margined laterally, posteriorly, anteriorly and along median suture with dark brown pigment; disk pale brown. Femora mostly pale brown, tibiae dark at knee but pale brown over most of surface ( Fig. 5 ). Wings with pale brown tint.

Male. Brachypterous, forewing length ca. 5 mm. Hemitergal lobes short, finger-like, projecting upward in lateral aspect and slightly forward of median in dorsal aspect ( Figs. 2-4 ); apical third and dorsal margin of hemiterga dark brown. Tergum 9 bearing a median hump covered with a circular patch of small sensilla basiconica ( Fig. 2 ).

Female. Macropterous, forewing length ca. 26 mm. Subgenital plate projects over base of sternum 9 as a short triangular process with shallow median notch on posterior margin ( Fig. 6 ). Vagina a membranous flattened bag with rectangular outline and short, partially fused accessory glands at anterior angles; anterior margin of vagina bearing a median sclerite and posterior half sparsely lined with fine setal spines ( Fig. 7 ). Spermatheca swollen, balloon-like and attached to vagina by a short, slender stalk.

Larva. Unknown.

Egg. Outline oval, length ca. 420 μm, equatorial width ca. 354 μm ( Fig. 8 ). Collar button- like, set on a raised, disc-like platform ca. 100 μm in diameter; margins irregularly crenulate and bearing short, obscure vertical struts ( Figs. 8-10 ); anchor a relatively plain membranous bell-shaped structure with short cylindrical pedicel ( Fig. 9 ). Chorionic surface punctate throughout, but mesal band including mixed larger, regularly spaced punctations and smaller irregularly spaced ones ( Fig. 11 ); punctations on anterior pole shallow, fine and barely discernable at 500X. Micropylar row subequatorial, set ca. 135 μm from anterior end.

Etymology. The species name, used as a noun in apposition, is based on the Bhutanese word for dragon people, and honors the people and history of Bhutan.

Diagnosis. Males of this species are distinguished by the short, upwardly directed hemiterga and females by the triangular, projecting and apically notched subgenital plate. This species is the only known Claassenia in which the egg form varies from the usual spindle shape.

Figures

Figs. 1-7. Claassenia drukpa structures. 1. Head and pronotum. 2. Male genitalia, dorsal. 3. Male hemitergum and cercal base, lateral. 4. Male hemitergum, lateral. 5. Foreleg. 6. Female abdominal sterna 8-9. 7. Vagina and spermatheca.

Figs. 8-11. Claassenia drukpa egg. 8. Egg, lateral. 9. Collar end with anchor. 10. Collar end, apical aspect. 11. Chorionic detail.