Scientific name - Taxonomic position - Diagnosis - Images - Hosts - Distribution - Mass Production - References

Scientific name 

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

Taxonomic position

Hymenoptera: Braconidae: Braconinae

Diagnosis

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 male 22-27. Setae of vertex more adpressed, mostly not reaching above upper 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

Images

   

   

   

Bracon brevicornis parasitising the larva of Opisina arenosella (Walker)

          Adult female - dorsal 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

Hosts

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).

Distribution

Cosmopolitan.

Mass production

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

References

  • Puttarudriah, M. & Channabasavanna, G.P. 1956. A study on the identity of Bracon hebetor Say and Bracon brevicornis Wesmael. Bulletin of Entomological Research, 1956: 

  • Singh, S.P. 1995. Technology for production of natural enemies. Technical Bulletin No. 4, Project Directorate of Biological Control, Bangalore-24. 221 p.

  • Sudheendrakumar, V.V., Mohamed, U.V.K., Abdurahiman, U.C. & Narendran, T.C. 1978. Mating behavior of Bracon brevicornis Wesmael (Hymenoptera: Braconidae), a larval parasite of Nephantis serinopa Meyrick, the black headed caterpillar of coconut. Agricultural Research Journal, Kerala, 16: 224-226.

  • van Achterberg, C. & Walker, A.K. 1998. 17. Braconidae, pp. 137-185. In: African cereal stem borers: Economic importance, taxonomy, natural enemies and control (Ed. A. Polaszek). CAB International / CTA. 530 p.

  • Zaki, F.N., Elsaadany, G., Gomaa, A. & Saleh, M. 1994. Some biological factors affecting the production of the larval parasitoid Bracon brevicornis Wesm. (Hym., Braconidae). Journal of Applied Entomology, 118 (4-5): 413-418.

Image credit

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