Chelonus (Megachelonus) adii, Ranjith & Priyadarsanan, 2023

Ranjith, A. P. & Priyadarsanan, Dharma Rajan, 2023, New subgeneric reports of the genus Chelonus (Hymenoptera: Braconidae) from India and Sri Lanka with description of nine species, Zootaxa 5278 (3), pp. 461-492 : 471-472

Chelonus (Megachelonus) adii sp. nov.

( Figures 6–7 )

urn:lsid:zoobank.org:act:53BD61E1-3837-4379-A942-6C3204408FBA

Material examined. Holotype, female, INDIA: Arunachal Pradesh, Pasighat , 28°06’51 N, 95°17’15 E, 715 m. a.s.l., 25.iv–15.v.2022, coll. A.P. Ranjith ( AIMB) . Paratype, 1 female same data as holotype ( AIMB).

Description. Holotype, female, length of body 3.2 mm, fore wing 2.5 mm.

Head. Antenna with 16 antennomeres, apical antennomeres not broadened, shorter than basal antennomeres ( Fig. 6A ); third antennomere 1.3 × longer than fourth; third, fourth and terminal antennomeres 4.2 ×, 3.8 × and 2.5 × longer than wide, respectively; head transverse ( Fig. 6B ), in dorsal view roundly contracted behind eyes ( Fig. 6C ); OOL: OD: POL= 1.8: 1.0: 1.5; longitudinal diameter of eye 1.7 × height of temples; vertex coarsely striate-rugose ( Fig. 6C ); frons distinctly concave, reticulate-rugose medially with a complete midlongitudinal carina, longitudinally striate laterally ( Fig. 6C ); occiput transversely striate-rugose ( Fig. 6C ); temple longitudinally striate-rugose ( Fig. 6A ); face coarsely reticulate-rugose laterally, transversely striate-rugose anteriorly, densely setose in lateral view ( Fig. 6B ); clypeus flat and sparsely punctate, smooth and shining ( Fig. 6B ); length of malar space 1.8 × basal width of mandible.

Mesosoma. Length of mesosoma 1.4 × its height; pronotum rugose laterally, smooth posteriorly ( Fig. 6D ); mesoscutum areolate-rugose, with longitudinal depressions medially ( Fig. 6E ); notauli impressed as large pits ( Fig. 6E ); transverse suture distinct, deep ( Fig. 6E ); scutellar sulcus divided by six carinae ( Fig. 6E ); scutellum punctate medially, sparsely setose, with crenulate groove laterally ( Fig. 6E ); mesopleuron evenly convex, coarsely reticulate-rugose, setose ( Fig. 6D ); metanotum crenulate with distinct midlongitudinal carina ( Fig. 6F ); propodeum with medial and lateral tubercles, coarsely reticulate-rugose, with triangular areola delineated by carina, transversal carina indistinct, but complete ( Fig. 6F ).

Wings. Fore wing infuscate subapically ( Fig. 7D ); length of fore wing 2.5 × its width; length of marginal cell 1.3 × pterostigma; vein 2-Rl present ( Fig. 7D ); vein r longer than 3-SR ( Fig. 7D ); r: 3-SR: SRl = 1.3: 1.0: 5.3; SRl straight; parastigma distinctly swollen ( Fig. 7D ); 1-CU1: 2-CU1= 1.0: 2.2; vein CUlb present ( Fig. 7D ).

Legs. Hind coxa smooth, densely short setose ( Fig. 7A ); hind femur robust ( Fig. 7A ); length of hind femur, tibia and basitarsus 2.9 ×, 3.8 × and 5.0 × their maximum width, respectively; mid and hind tibia with numerous short, pointed spines apical half ( Fig. 7A ).

Metasoma. Metasomal carapace elongate-oval in dorsal view, coarsely reticulate-rugose, with a pair of posteriorly converging midlongitudinal carinae basally ( Fig. 7B ); length of carapace 2.0 × its maximum width in dorsal view; carapace without undulating lamella laterally ( Fig. 7A ); ventral cavity closed apically, with a pair of short and blunt teeth ( Fig. 7C ); ovipositor long, slender and the ovipositor sheath 0.07 × as long as fore wing, 0.3 × as long as hind tibia.

Colour. Black except eyes grey, maxillary and labial palps, fore coxa, trochanter, mid coxa, trochanter, mid femur basally, hind coxa apically, hind trochanter, mid and hind tibia subbasally, fore wing basally, metasomal carapace basolaterally, mid and hind tibial spurs yellow, fore femur, fore tibia, hind trochantellus apically reddish brown.

Male. Unknown.

Biology. Unknown.

Distribution. India (Arunachal Pradesh).

Etymology. The new species is dedicated to the Adi people, the indigenous group in the state Arunachal Pradesh.

Comparative diagnosis. The new species is coming near to C. (M.) biligiriensis sp. nov. from South India in having the similarities mentioned in the key. Apart from the differences cited in the key the new species differs from C. (M.) biligiriensis sp. nov. by pronotum smooth posteriorly (rugose in C. (M.) biligiriensis sp. nov.), coxae yellow (reddish in C. (M.) biligiriensis sp. nov.), temple striate (rugose in C. (M.) biligiriensis sp. nov.), hind coxa smooth (striate dorsally in C. (M.) biligiriensis sp. nov.), carapace without undulating lamella laterally (with lamella in C. (M.) biligiriensis sp. nov.).

Figures

FIGURE 6. Chelonus (Megachelonus) adii sp. nov., holotype, female A) habitus, lateral view; B) head, anterior view; C) head, dorsal view; D) mesosoma, lateral view; E) mesosoma, dorsal view; F) propodeum, dorsal view.

FIGURE 7. Chelonus (Megachelonus) adii sp. nov., holotype, female A) metasoma, lateral view; B) metasoma, dorsal view; C) apex of metasoma, dorsal view; D) wings.