Occipitotus Singh & van Achterberg, 2022

Singh, Longjam Roni Kumar, Achterberg, C. Van & Sheela, S., 2022, Studies on the subfamily Exothecinae (Hymenoptera: Braconidae) with the description of a new genus and a new species from India, Zootaxa 5133 (1), pp. 40-52 : 43

Occipitotus Singh & van Achterberg gen. nov.

( Figures 2–6 )

Type species: Occipitotus langpramensis Singh & van Achterberg sp. nov.

Etymology. The generic name Occipitotus is masculine and refers to the complete occipital carina on the head; “occipit” stands for occipital carina and “totus” (Latin for “complete”).

Diagnosis. Antenna with 22–30 flagellomeres (25–30 in female; 22–28 in male), longer than fore wing ( Figs 2B , 4B ), scapus small, subglobose, shorter ventrally than dorsally; occipital carina complete ( Figs 3A , 4C ), ventrally straight or slightly curved reaching base of mandible (rarely reduced near base of mandible) and raised into a flange; remaining widely separated from hypostomal carina ( Figs 6A–E ); hypoclypeal depression deep and small ( Fig. 2E ); clypeus slightly convex or flat, not protruding beyond the level of the face ( Fig. 2A ); malar suture obsolescent; pronope large and deep ( Figs 3F , 4C ); mesoscutum glabrous and shiny; notauli finely crenulate, terminating into rugose area posteriorly ( Figs 3B , 4D ); vein r of fore wing distinctly oblique and arising from basal 0.4–0.5 of pterostigma; first subdiscal cell of fore wing elongate ( Figs 5B, 5D ); fore wing vein 1-M of male widened, as wide as or slightly wider than length of cu-a ( Fig. 5D ); propodeum coarsely rugose-reticulate, with weak median carina anteriorly ( Fig. 4D ) or entire; dorsal carinae of metasomal tergite I not united medially and tergite coarsely rugosereticulate with (feeble) ( Fig. 3C ) or without ( Fig. 3G ) median carina; metasomal tergite II longitudinally striate (nearly) complete ( Figs 3C , 4A ) or anterior half striate ( Fig. 5A ); tergite II slightly longer than tergite III, feebly striate antero-laterally ( Fig. 4A ) or smooth and shiny ( Fig. 5A ); tergites IV–VI smooth and sparsely setose ( Figs 3C , 4A ); length of ovipositor sheath 0.5–0.7 times as long as first tergite ( Figs 2B , 4A ).

Biology. Host unknown, but collected from horsetails, Equisetum sp. ( Equisetaceae ; Fig. 7B ) along with an unidentified species of Coleoptera ( Chrysomelidae ; Fig. 7A ); considering the biology of other species of the members of this subfamily Exothecinae , it is likely to be an ectoparasitoid of coleopterous larvae on Equisetum sp.

Distribution. Oriental.

Figures

FIGURES 2(A–F). Occipitotus langpramensis sp. nov., holotype, female. (A) Head, lateral view; (B) habitus, lateral view; (C) apex of antenna; (D) base of antenna; (E) head, frontal view; (F) mesosoma, lateral view. Scale bars = 0.2 mm (A, C, D, E, F); 0.5 mm (B).

FIGURES 3(A–G). (A–E) Occipitotus langpramensis sp. nov., holotype, female. (A) Head, dorsal view; (B) mesosoma, dorsal view; (C) metasoma, dorsal view; (D) apex of metasoma, showing ovipositor sheath and ovipositor; (E) ovipositor; (F–G) paratype, female. (F) Pronotum, dorsal view, showing pronope; (G) propodeum + metasomal tergite I, dorsal view. Scale bars = 0.2 mm (A, B, C, D, F, G); 0.1 mm (E).

FIGURES 4(A–D). (A) Occipitotus langpramensis sp. nov., paratype, female, metasoma, dorsal view; (B–D), paratype, male; (B) habitus, lateral view; (C) head + pronotum, dorsal view, showing pronope; (D) mesosoma, dorsal view. Scale bars = 0.2 mm (A, C, D); 0.5 mm (B).

FIGURES 5(A–D). (A, D) Occipitotus langpramensis sp. nov., paratype, male. (A) Metasoma, dorsal view; (D) fore wing; (B–C) paratype, female. (B) fore wing; (C) hind wing. Scale bars = 0.2 mm (A); 0.5 mm (B, C, D).

FIGURES 6(A–E). Occipitotus langpramensis sp. nov., head, latero-posterior view. (A) Holotype, female; (B–E) paratypes. (B–D) females; (E) male. Scale bars = 0.2 mm.

FIGURES 7(A–B). (A) Unidentified species of Coleoptera (Chrysomelidae); (B) horsetails, Equisetum sp. (Equisetaceae).