Tyloperla barog, Stark & Sivec, 2014

Stark, Bill P. & Sivec, Ignac, 2014, Three New Species Of Tyloperla Sivec & Stark (Plecoptera: Perlidae) From India, Illiesia 10 (4), pp. 32-42 : 36-38

Tyloperla barog sp. n.

( Figs. 13-20 )

Material examined. Holotype ♂ and 1 ♀ paratype, India, Himachal Pradesh, Barog, Solan District , 1550 m, 17 July 1992, J.M. Julka, B. Bala ( PMSL).

Adult habitus. General color brown, patterned with yellow-brown. Head with an area of dark brown pigment between ocelli which extends to anterior ocellus and laterally, forward of callosities; lappets without dark pigment, antennae brown ( Fig. 13 ). Pronotum with pale brown pigment over most of disc, but with a narrow, pale median band and numerous rugosities.

Male. Forewing length 19 mm. Abdominal sterna 4–7 bearing hair brushes. Hemiterga with well developed, oval basal callus bearing small sensilla basiconica on inner margins ( Fig. 14 ); anterior process of hemiterga slender, tapered to a rounded apex and bearing a few sensilla scattered along the dorsoapical surface. Tergum 9 unmodified, tergum 8 with a small mesal projection and a median patch of numerous sensilla basiconica. Aedeagus armed with a few, relatively large apical spines and thin setal-like spines form a row along the ventrolateral margin of the sac and a small patch near the ventrolateral margin of the tube; tube mostly membranous and swollen near midlength ( Fig. 15 ).

Female. Forewing length 23 mm. Subgenital plate on sternum 8 projecting over about half of sternum 9, triangular with a small median notch ( Fig. 16 ).

Egg. Outline oval. Length ca. 320 μm, equatorial width ca. 265 μm ( Fig. 17 ). Collar short, height ca. 20 μm, width ca. 139 μm; rim of collar flanged and irregularly incised, sides bearing ca. 8 vertical ridges in lateral aspect ( Fig. 18 ). Surface coarsely pitted in a broad zone ca. 124 μ wide surrounding collar ( Figs. 17-20 ) and in a similar zone ca. 96 μm wide on lid ( Fig. 20 ); equatorial zone without pits ( Fig. 17 ). Eclosion ring absent. Micropyles not observed. Only three poorly cleaned and broken eggs were suitable for SEM study.

Larva. Unknown.

Etymology. The species name, based on the type locality, is used as a noun in apposition.

Diagnosis. This species is generally similar in hemitergal structure to T. attenuata (Wu & Claassen) and T. schmidi Stark & Sivec , but differs from both in lacking a sensilla basiconica patch on tergum 9 ( Wu & Claassen 1934; Stark & Sivec 1991). In addition, the new species may be separated from T. attenuata by the acute hemitergal apices in that species and from T. schmidi by the presence of prominent lateral lobes on the aedeagus of that species. Females for these congeneric species are unknown, however the female subgenital plate is similar to that of T. formosana (Okamoto) , although the median notch in that species is deeper and the plate reaches beyond midlength of sternum 9 ( Sivec et al. 1988). The eggs of the new species are the only known for the genus in which the chorion is coarsely pitted around both polar areas, but smooth over the equatorial zone.

Figures

Figs. 13-16. Tyloperla barog structures. 13. Head and pronotum. 14. Male terminalia, dorsal. 15. Aedeagus, lateral. 16. Female terminalia, ventral.

Figs. 17-20. Tyloperla barog egg structures. 17. Entire egg, lateral aspect. 18. Collar end. 19. Chorionic detail, lid. 20. Lid.