Rhyacophila Pictet, 1834

Genus: Rhyacophila Pictet, 1834 View in CoL

Type species: Rhyacophila vulgaris Pictet, 1834 View in CoL (designated by Ross, 1944: 32)

Ross, 1956 & Schmid, 1970

Branch: Rhyacophila divaricata View in CoL

Subbranch: Rhyacophila curvata

Group: Rhyacophila tarkiya Group

Rhyacophila sivaramakrishnani sp. nov. Ali, Hussain, Majeed ( Figs 1 A‒D View FIGURE 1 )

Holotype male: INDIA, Himachal Pradesh, Panchpulla ; 32°31'33.8"N 75°59'21.7"E; 28.v.2022, 1999 amsl; 1 male GoogleMaps . Paratype: 2 males, same data as for holotype. Leg. Tabraq Ali, Aquib Majeed, Zahid Hussain GoogleMaps .

Diagnosis.

The male genitalia of Rhyacophila sivaramakrishnani sp. nov. are similar to those of Rhyacophila tarkiya Schmid, 1970 (reported from Sikkim, India) but (1) the dorsal margin of segment IX is nearly convex in R. sivaramakrishnani sp. nov. whereas it is dorso-posteriorly rounded in R. tarkiya ; (2) segment X of R. sivaramakrishnani sp. nov. is posteriorly triangular with blunt apex n lateral view but posteriorly bilobed in R. tarkiya in lateral view; (3) notch in caudal margin of bilobed apical segment deeper in in R. sivaramakrishnani than in R. tarkiya ; (4) dorsal lobe of apical segment broad and rounded apically in R. sivaramakrishnani sp. nov. whereas dorsal lobe of apical segmentr shorter in R. tarkiya ; (5) ventral lobe of apical segment stout and apically rounded in Rhyacophila sivaramakrishnani sp. nov. whereas directed ventrad and triangular with blunt apex in R. tarkiya ; (6) phallus is regularly tapering and pointed in R. sivaramakrishnani sp. nov. but broad in the proximal 2/3 rds and tapering in the distalmost 1/3 rd towards the apex in R. tarkiya .

Description. Adult male ( Fig. 1 C View FIGURE 1 ). Color in alcohol brown, head dorsally dark brown, antennae brown, legs light brown. Length of each antenna 4.4 mm. Wings fuscous; length of each forewing 7.2 ± 0.3 mm (n=3); fork II arises before fork I; ( Fig. 1 D View FIGURE 1 ). Body length from tip of head to apices of folded forewings about 9 mm.

Male genitalia ( Figs. 1 A‒B View FIGURE 1 ). In lateral view, tergum of segment IX slightly convex and longer than sternum. Anal sclerite dorso-posteriorly triangular. Segment X in lateral view stout, apically somewhat triangular with blunt apex; in dorsal view sclerotised, 1/3 rd from base narrow, cylindrical, 2/3 rd broad, rounded apically with small indent in inner margin; segment X posteriorly with deep U-shaped emargination. Inferior appendages in lateral view with basal segment ½ from base stout, distal half rectangular and slightly convex apically and apical segment shorter than basal segment, bilobed with broad U-shaped emargination, dorsal lobe smaller than ventral and both lobes rounded apically. Phallotheca asymmetrical, directed caudo-ventrad. Dorsal appendage of phallic apparatus dorso-mesally convex, preapically notched, curved antero-dorsad and pointed apically. Endotheca membranous, broad and sinuous laterally. Phallus strong, broad at base, tapering towards apex and pointed apically. Parameres regular, run parallel with phallus, equal in length with phallus and pointed apically.

Distribution: India, Himachal Pradesh.

Etymology: The species is named in honor of Dr. K. G. Sivaramakrishnan, Professor in the Department of Zoology, Madras Christian College, Tambaram East, Chennai, India, in recognition of his exceptional contributions to entomology, and the biodiversity of aquatic insects of India in particular.