Rhytidothorax ramakrishnai, Hayat, Mohammad & Kazmi, Sarfrazul Islam, 2011

Hayat, Mohammad & Kazmi, Sarfrazul Islam, 2011, On some Encyrtidae (Hymenoptera: Chalcidoidea) from Namdapha Tiger Reserve in Arunachal Pradesh, India, Zootaxa 2830, pp. 1-19 : 7-9

Rhytidothorax ramakrishnai sp. nov.

( Figs 15–21 )

Female. Holotype. Length, 1.91 mm. Body completely dark brown to black; frontovertex bluish green, scrobal impression and malar space slightly violet; mesoscutum with a slight bluish shine; scutellum purple, slightly greenish on sides; metanotum, propodeum and gaster black. Antenna ( Fig. 15 ) with radicle brown; scape brownish yellow, brownish at base and apex; pedicel and F1–4 dark brown; F5 brown in basal half; apical half of F5, F6 and clava yellow. Fore wing ( Fig. 16 ) subhyaline, lightly infuscate below distal third of submarginal and distal veins, and beyond venation with a strongly infuscate broad band in anterior half and an infuscate streak in posterior half. Hind wing hyaline, lightly infuscate in apical third. Legs with mid coxa black, but otherwise yellow to brownish yellow with brownish suffusions.

Head. Eyes nearly reaching occipital margin posteriorly; scrobes U-shaped, with rounded margins; antennal toruli slightly less than their heights to mouth margin (9.5: 8) and their upper margins slightly above lower margin of eyes ( Fig. 18 ); ocellar triangle with apical angle right angle or slightly obtuse triangle; posterior ocellus about one ocellus diameter to occipital margin, and slightly less than one diameter to eye margin; POL about 2.61x as long as OOL, and about 2.12x as long as OCL; frontovertex with fine, slightly raised polygonal reticulations and with small setigerous punctures on vertex, and a line of punctures along each eye margin; eyes setose, setae hyaline, and each seta clearly longer than a facet. Mandible with one pointed tooth, a receding ventral tooth, and a small, receding dorsal truncation. Maxillary palp 4-segmented, labial palp 3-segmented. Antenna as in Fig. 15 ; scape nearly 6x as long as broad; F1 longer than pedicel and 5x as long as broad; clava slightly longer than F5 and F6 combined. Relative measurements — head dorsal width, 50; frontovertex width at anterior ocellus, 20.5; eye height, 33; malar space, 15; POL, 8.5; OOL, 3.25; OCL, 4; AOL, 5.5.

Mesosoma. Mesoscutum with irregular polygonal reticulations and fine setigerous punctures; scutellum with very fine reticulations hardly deeper than on mesoscutum except sides and apex narrowly smooth; mesopleuron smooth; propodeum with a median ridge and an inwardly curved ridge mesal to each spiracle ( Fig. 19 ); setae on thoracic dorsum brown, but those on sides of propodeum silvery white. Fore wing ( Fig. 16 ) 3.23x as long as broad; venation extending 0.51x wing length; marginal vein clearly longer than postmarginal vein or stigmal vein. Hind wing 4.46x as long as broad; venation extending 0.6x wing length; marginal cell with a line of moderately long setae. Fore leg with last tarsal segment with a short comb of setae. Relative measurements — mesoscutum length (width), 33 (50); scutellum length (width), 35 (26.5); propodeum median length, 14; (paratype, slide) — median length of propodeum: scutellum length = 14: 32.5.

Gaster about 0.64x as long as mesosoma; hypopygium with apex rounded and with a small median notch; third valvula distinctly articulated with second valvifer ( Fig. 17 ). Relative measurements (paratype, slide) — TVII length, 45; ovipositor length, 35; third valvula length, 6; mid tibia length, 82; mid basitarsus length, 24; mid tibial spur length, 27.5.

Male. Similar to female in colour, but smaller (about 1.5 mm) and as follows. Frontovertex 0.45x head width; antennal toruli with lower margins above lower margins of eye, and separated from mouth margin by a distance greater than (8) torulus height (6.75). Antennal formula, 1, 1, 6, 1 ( Fig. 20 ); pedicel subtriangular; F1 longer than pedicel; F1–6 with long setae. Genitalia ( Fig. 15 ) with parameres absent; digiti short, each digitus with a denticle; phallobase shorter than mid tibial spur (15.5: 22.5).

Material examined. Holotype, female (on card) labelled “ INDIA: Arunachal Pr. Namdapha Tiger Reserve, Road to Ranijheel, 11.xi.2009, P.M.Sureshan” (“ NZSI 12342/H3” on a red ticket).

Paratypes. 1 female (on slide, No. EH 1313, one antenna missing), 1 male (on slide, EH 1312, one clava missing) with same data as holotype. ( ZDAMU, Registration No. HYM. CH. 619).

Host. Unknown.

Distribution. India: Arunachal Pradesh.

Comments. This species is placed in Rhytidothorax because it has a majority of the characters of this genus, but with some hesitation because of the presence of distinctly articulated third valvulae (= gonostyli). Except for the presence of articulated third valvulae, it is similar to R. nigrum Singh & Agarwal (1993a , b), but differs from it in the characters given in the key. Earlier, Hayat et al. (2002) described R. callistus with articulated third valvulae (see key to species).

Etymology. This species is named after Dr. Ramakrishna, former Director, Zoological Survey of India, for providing encouragement to collect animals in remote areas of the country.

Figures

FIGURES 15 – 21. Rhytidothorax ramakrishnai sp. nov., female, except Figs. 20 and 21: 15, antenna; 16, fore wing; 17, ovipositor; 18, head, front view; 19, distal part of mesosoma; 20, male antenna; 21, male genitalia.