Bracon (Habrobracon) brevicornis (Wesmael) (=Bracon brevicornis (Wesmael))

Hymenoptera: Braconidae: Braconinae

Length of fore wing 1.9-2.6 mm, of body 1.8-2.6 mm. Colour is very variable: body nearly completely yellowish brown to largely dark brown or black, with frons, orbits, vertex anteriorly, face laterally, pronotum dorsally, notaulic area, scutellum (except usually medioanteriorly), first tergite (except medioposteriorly) and following tergites laterally pale yellowish; basal two-thirds of wings more or less infuscate, remainder of wings subhyaline, but sometimes infuscate apically; pterostigma rather dark brown, with sometimes a (faint) pale basal spot. Antenna of female (Fig. 1-2) with 15-18 segments, submoniliform, slightly longer than length of head and mesosoma combined; antenna of male 22-27-segmented (Fig. 3). Setae of vertex comparatively adpressed, mostly not reaching above upper level of posterior ocellus (Fig. 4); clypeus nearly flat to convex (Fig. 4); clypeus, face and frons finely granulate; setae of face rather short; vertex mainly smooth; mesoscutum largely setose, shiny, smooth; scutellar sulcus narrow and distinctly crenulate; vein 3-SR of fore wing 1.2-1.8 times vein r, veins 1-SR and 3-SR short, but 1-SR may be rather long (Fig. 5); marginal cell of fore wing medium-sized, ending distinctly removed from apex of wing (Fig. 5); tarsal claws with small acute lobe; propodeum superficially granulate; length of first tergite about 0.8 times its apical width, its surface smooth; dorsolateral carinae of first tergite absent; second tergite without mediobasal area; second metasomal suture rather deep, nearly straight and finely crenulate; second to seventh segments superficially granulate, shiny; length of ovipositor sheath 0.20-0.29 times fore wing and about twice length of first tergite (modified from van Achterberg & Walker, 1998).

This species is closely related to another common species, Bracon (Habrobracon) hebetor (Say), from which it can be identified by the following characters: Antenna of female with 15-18 segments, slightly longer than length of head and mesosoma combined; antennal segments of level of posterior ocellus; vein 3-SR of fore wing 1.2-1.8 times vein r.

 Fig. 1-3. Adult female, lateral view; 2. Female antenna, apical segments; 3. Male antenna
 Fig. 4. Head, showing setae on vertex; clypeus, lateral margin
 Fig. 5. Fore wing venation

 
 
 
Bracon brevicornis parasitising the larva of Opisina arenosella (Walker)

   Adult female - dorsal view
   Adult - dorsal & lateral view
     Eggs of B. brevicornis on the larva of Opisina arenosella
   Early instar larvae of B. brevicornis on O. arenosella
   Fully grown larva of B. brevicornis feeding on O. arenosella
     Mature larva of B. brevicornis
 Pupae of B. brevicornis in silken cocoons

Cosmopolitan.

An extremely polyphagous ectoparasitoid, attacking Crambidae and Pyralidae in stored products and in the field; in the field other lepidopterous families may also be attacked (van Achterberg & Walker, 1998). Important hosts include Opisina arenosella (Walker), Chilo partellus (Swinhoe), Pectinophora gossypiella (Saunders); Corcyra cephalonica (Stainton) (factitious laboratory host, used widely for mass production in Indian insectaries).

Mass produced on the common laboratory host, Corcyra cephalonica (Stainton). Singh (1995) has given the detailed production procedure for B. brevicornis and C. cephalonica.

The line drawings are redrawn from van Achterberg and Walker (1998).