Centistidea yamu Ranjith & Priyadarsanan sp. nov.

(Figures 13–14)

urn:lsid:zoobank.org:act: 2938672F-EA05-47CF-9D33-1AB9CD2EC936

Material examined. Holotype. ♀ INDIA: Arunachal Pradesh, Ramsing, 28°65.538’ N, 94°97.543’ E, 2087 m.a.s.l., secondary evergreen forest, Malaise trap, 9–12.v.2022, coll. Ranjith, A.P. (AIMB).

Description. Female

Body measurements. Length of body 2.2 mm, length of fore wing 2.5 mm.

Head. Antenna with 14 antennomeres, all antennomeres longer than wide (Fig. 13A). First flagellomere 1.1 × as long as second flagellomere. First, second and penultimate flagellomeres 4.8, 4.6 and 2.4 × as long as wide. Maxillary palp with four segments (Figs 13A, B), fourth segment 1.2 × as long as third segment. Face distinctly convex medially and laterally (Fig. 13B), 1.5 × as wide as long, smooth, setose. Clypeus 2.4 × wider ventrally than medially high with convex posterior margin (Fig. 13B). Malar suture distinct (Fig. 13B). Length of malar space 1.2 × basal width of mandible. Mandible distinctly twisted (Fig. 13B), inner tooth distinctly shorter than outer tooth. Frons smooth, convex medially, setose (Fig. 13C). Vertex smooth, setose (Fig. 13C). OOL: transverse diameter of posterior ocellus: POL= 2.8: 1.0: 1.2. Length of eye 1.4 × as long as temple in dorsal view.

Mesosoma. Mesosoma 1.4 × as long as high. Pronotum and propleuron smooth laterally (Fig. 13D). Mesoscutum punctate in anterior half smooth posteriorly, setose, carinate postero-laterally (Fig. 13E). Notauli only impressed anteriorly, faintly crenulated (Fig. 13E). Scutellar sulcus represented only by a transverse groove, not crenulated (Fig. 13E). Scutellum evenly setose, smooth (Fig. 13E), with a pair of large pits medio-posteriorly separated by a carina, sides of scutellum irregularly sculptured (Fig. 13F). Mesopleuron smooth, glabrous, setose ventrally (Fig. 13D). Metapleuron with a deep small pit antero-dorsally, with deep shallow longitudinal depressed line, glabrous (Fig. 13D). Propodeum with a distinct and complete medio-longitudinal carina absent behind costula, dorsal part of midlongitudinal carina associated with irregular sculpture, sparsely setose, antero-lateral part with shallow declivity, postero-lateral part faintly crenulated, posterior part well differentiated from dorsal part, posterior transverse carina distinct (Fig. 13F).

Wings. Fore wing: Vein r distinct, 0.3 × as long as 2RS (Fig. 14C). R1 distinct, wide (Fig. 14C). Vein (RS+M)b 0.6 × as long as 1m-cu. Vein 1-M 1.5 × as long as m-cu. Vein (RS+M)a 2.6 × (RS+M)b. Vein 1CUa thickened, 0.6 × as long as 1CUb (Fig. 14C). Hind wing: Vein cu-a straight. Veins M+CU: 1M: 1r-m= 2.3: 2.7: 1.0.

Legs. Hind coxa smooth, setose (Figs 13A, 14A). Tarsal claws without basal lobe. Hind femur, tibia and basitarsus 4.2, 10.4 and 4.6 × as long as wide respectively.

Metasoma. First tergite smooth, widening medially, weakly narrowing apically, distinctly narrowing basally, 3.4 × as long as its maximum width (Fig. 14B). Second tergite longitudinally striate, setose, medial length 0.7 × as long as third tergite (Fig. 14B). Third tergite longitudinally striate, setose (Fig. 14B). Ovipositor straight. Ovipositor sheath 0.1 × as long as fore wing, slightly narrowing apically with long setae apically (Figs 14A, B).

Colour. Body reddish brown except face, clypeus, mandible, maxillary and labial palps, vertex laterally, tegula, legs except hind tarsus yellow.

Male. Unknown.

Etymology. The species is named after its brown body; “ yamu ” is brown the language of Adi indigenous people of Arunachal Pradesh.

Biology. Unknown.

Distribution. India (Arunachal Pradesh).

Comparative diagnosis. The new species is coming close to C. sii (Maetô, 1995) by the following characters, pterostigma brown, first flagellomere 1.1 × as long as second flagellomere and mesoscutum brownish. However, the new species differs from the latter in having the following differences; length of eye 1.4 × as long as temple in dorsal view (1.1 × in C. sii), first flagellomere 4.8 × as long as wide (5.0–6.0 × in C. sii), OOL 2.3 × POL (1.6 in C. sii) and hind femur 4.2 × as long as wide (3.6–3.8 × in C. sii).