Brachygaster rarum, Rameshkumar & Huben & Kazmi, 2021

Rameshkumar, Anandhan, Huben, Mike R. & Kazmi, Sarfrazul Islam, 2021, First report of the genus Brachygaster Leach (Hymenoptera: Evaniidae) from India with two new species, Zootaxa 5052 (1), pp. 145-150 : 146

Brachygaster rarum sp.nov.

( Figs 1–6 )

Description. Holotype female. Body length 3.8 mm (Head to tip of metasoma).

Head. Black, quadrate, deeply punctured with an arch-like pattern of sculptures; ocelli and eyes silvery; genae deeply punctured and sculptured; post orbital carinae present, extending from clypeus to mid inner margins of eyes; silvery hairs uniformly scattered on the face; mandibles bidentate; fronto-vertex length half of the head width as well as scape length; distance between posterior ocellus 2.3 × of the distance between anterior ocellus, 3.5 × of posterior ocellus and eye margin; malar space equal to scape length and distance between posterior ocelli; eyes ovoid. Antenna with 13 antennomeres (excluding radicle), thickened towards the tip; radicle, scape, pedicel, F1–F8 yellowish- brown, remaining flagellomeres brown; longitudinal sensillae visible; antennal sockets arise at about 1/3 base of eyes; pedicel and F1 quadrate, remaining flagellomeres longer than broad; scape 3 × longer than broad, slightly longer than pedicel, F1 and F2 combined, 2.3 × shorter than eye length. Relative measurements (in mm)— head width (height), 1.3 (1.2); fronto-vertex width, 0.6; POL, 0.35; AOL, 0.15; OOL, 0.1; eye length (width), 0.7 (0.5); malar space length, 0.3; scape length (width), 0.3 (0.1); pedicel length (width), 0.09 (0.09); F1 length (width), 0.08 (0.08); F2 length (width), 0.1 (0.08).

Mesosoma. Black, pronotum short, with silvery setae; pronotal neck obscure; dorsolateral area of pronotum with the sharp ending; carinae present on lateral sides of pronotum; pronotal carina inconspicuous in the mid-dorsal area and prominent in lateral view. Mesoscutum about 2.0 × longer than broad, nitid with regular fovea; notaulus absent; tegulae testaceous; transverse sculpture with silvery setae present; anterior mesoscutal sulcus, parascutal carina and parascutal sulcus present. Mesoscutellum about 3.0 × broader than long, nitid with regular foveae; an arch-like pattern of sculpture with silvery-white setae. Metanotum: Lateral side covered by setae; metanotum and metascutellum form a continuous structure; metascutellum flat and nitid; epicnemial carina without median process; prespecular sulcus smooth and nitid. Propodeum with regular foveae; the dorsal propodeal area with long stiff setae; adpetiolar strip broader than long; nucha present and elevated (in lateral view).

Legs: Procoxa dark brown except basal part testaceous, remaining part of forelegs testaceous; mid-coxa dark brown except apex and remaining parts of mid legs testaceous; metacoxa dark brown except apex testaceous; hind femur, tibia, tarsi brownish; hind femur as long as hind tibia; spines present on the dorsal surface of hind tibia and hind tarsal segments; length of hind leg 2.8 × mesosoma height; external tibial spur half of the metatarsal length. Relative measurements (in mm)—mesosoma height, 1.2; mesoscutum length (width), 0.6 (1.1); scutellum length (width), 0.3 (0.9); hind leg length, 3.4; hind femur length (width), 1.0 (0.25); hind tibia length (width), 1.0 (0.2); internal tibial spur length, 0.25; external tibial spur length, 0.3.

Wings. Hyaline; fore wing with three complete cells; costal cell half of the combined length of head and mesosoma; costal cell 3.5 × as long as stigmal vein; stigmal vein as wide as costal cell; 4RS and r-m vein spectral; fore wing 2.3 × longer than wide. Relative measurements (in mm)—fore wing length (width), 2.8 (1.2); costal cell length (width), 1.05 (0.09); stigmal vein length (width), 0.30 (0.1); hind wing length (width), 1.5 (0.5).

Metasoma. Ovoid in shape; lustrous dark brown, smooth; ovipositor not exserted; petiole brown with longitudinal sculpture, not punctate, half of the metasoma length. Relative measurements (in mm)—petiole length (width), 0.6 (0.15); metasoma length (width), 1.1 (0.9).

Male. Unknown.

Host. Unknown.

Distribution. India: Maharashtra.

Material examined. Holotype, Female (on card), “ INDIA: Maharashtra, Satara, Soangaon, 08.iii.2009, net sweep, Coll. S. I. Kazmi ”.

Etymology. The species is named after its presumed rareness.

Comments. Brachygaster rarum sp. nov. is close to B. tschekylli Madl (1989) and B. conjugens Enderlein , however, the latter two differ by the following characters: in B. tschekylli : body red-brown; parapsidal furrows clearly developed; petiole dorsally smooth. In B. conjugens : metasoma coarse, triangular; POL= OAL= OOL; petiole 0.7 × of metasoma.

Figures

FIGURES 1–6. Brachygaster rarum sp.nov., Holotype ♀. 1. habitus; 2. head, frontal view; 3. antenna; 4. hind legs; 5. fore wing; 6. metasoma with petiole.