Brachymeria alternipes (Walker, 1871)

Narendran, T. C. & van Achterberg, Cornelis, 2016, Revision of the family Chalcididae (Hymenoptera, Chalcidoidea) from Vietnam, with the description of 13 new species, ZooKeys 576, pp. 1-202 : 23-24

Taxon classification Animalia Hymenoptera Chalcididae

Brachymeria alternipes (Walker, 1871) Figs 25, 26

Chalcis alternipes Walker, 1871: 49 (♂, Hong Kong (BMNH) (examined)).

Brachymeria alternipes ; Joseph, Narendran & Joy, 1973: 173; Narendran 1989: 245, 272.

Material.

1 ♂ (RMNH), "NW Vietnam: Tonkin, Hoang Lien N. R., SW Sa Pa, c 1550 m, 22-29.x.1999, Malaise traps, C. v. Achterberg, RMNH’99”.

Diagnosis.

This species resembles Brachymeria atridens (Walker) in general appearance, but differs from it in having: 1) scrobe distinctly reaching anterior ocellus (in Brachymeria atridens scrobe not reaching anterior ocellus); 2) very weak or indistinct pre-orbital carina, (in Brachymeria atridens pre-orbital carina strongly developed) and 3) hind femur without any patch (in Brachymeria atridens hind femur often with a black patch of varying size on disc).

Description.

♂, length of body 4.8-5.9 mm.

Colour. Black with cinereous pubescence; antenna black, radicula brown; tegula pale brownish yellow; fore and mid femora black with bases and apices pale brownish yellow; all trochanters black; hind femur red without a distinct apical yellow spot; hind tibia black with base and apex red.

Head. Head densely pubescent; head as broad as mesosoma; POL 1.7 × OOL in Vietnamese specimen; face and vertex with deep close umbilicate pits; scrobe smooth and shiny except area near anterior ocellus where it is rugulose, reaching anterior ocellus; antennal toruli situated well above level of lower eye margin; median area of face just below centre of interantennal projection slightly raised and smooth; labrum with approximately ten small round pits in Vietnamese specimen; malar space 0.4 × height of eye in profile; pre-orbital carina indistinct; post-orbital carina reaching geno-temporal margin. Antenna with scape densely pubescent dorsally, relative length: width of antennal segments of Vietnamese specimen: scape = 13:5; F1 = 8:7; F2 = 7:8; F3 = 6:8; F4 = 6:8; F5 = 5:7; F6 = 5:7; F6 = 5:7; clava = 14:7; antenna a little shorter than mesosoma.

Mesosoma. Pronotum with anterior margin carinate on sides; pronotum, mesoscutum and scutellum with close umbilicate pits. Interstices narrower than half diameter of a pit and mostly rugulose on anterior half of mesoscutum and on pronotum. Interstices smooth and carinate on scutellum; apex of scutellum emarginated and bi-lobed with dense pubescence all around posterior margin of scutellum. Upper dorsal margin of lateral panel of pronotum arched.

Wings. Fore wing 2.7 × longer than wide in Vietnamese specimen; MV a little more than 0.6 × length of SMV, a little more than 3 × as long as PMV; STV half-length of PMV; wing disc fully pilose; marginal fringe shorter than one-fourth length of STV.

Legs. Hind coxa without an inner ventro-mesal tooth, dorsal side smooth and shiny, ventral side punctate and pubescent; hind femur twice as long as its width with 9-10 irregular teeth on outer ventral margin, outer disc with close pits, interstices of pits smooth and shiny.

Metasoma. Oval, a little shorter than mesosoma; T1 smooth and shiny, its posterior margin straight; T2 with sparse minute pits on anterior half; pits denser laterally, micro-sculptured on posterior half, posterior margin straight; T3 shallowly and sparsely pitted, interstices reticulate; T4 to T6 with close setigerous pits, interstices mostly carinate.

Female. Similar to male.

Host.

Anteraea proylei Jolly ( Lepidoptera : Saturniidae (Chalpathy et al. 1998).

Distribution.

Vietnam (new record), India, South China.

Variation.

The Vietnamese specimen differs from the type as follows: hind femur with relatively small yellow spot at the junction of base of hind tibia and apical ventro-lateral part of hind femur; the male antenna length subequal to mesosomal length and metasoma a little longer than mesosoma (27:24).