Diagnosis – Male
funicle 4-segmented, with the first 3 segments branched; female funicle
3-segmented. Hind coxa
flattened and enlarged. Hind tibia
with alternating diamond shaped or wavy rows of dark setae. Notauli
absent. Scutellum
usually with 2 pairs of setae and without sublateral grooves. Dorsellum
with a triangular expansion which partly covers propodeum. Forewing
densely setose, long, narrow and wedge-shaped; numerous setae on submarginal
vein, marginal vein quite long, short postmarginal vein and reduced
stigmal vein. Propleura meeting or not posteriorly and covering prosternum.
Classification and distribution –
The tribe Elasmini is sufficiently distinctive that in the past it
has been considered a separate family (e.g. Boucek,
1988; Gibson et al.,
1997). However, recent DNA investigations (Gauthier
et al., 2000) have shown that Elasmini are belong in
the subfamily Eulophinae.
Elasmus Westwood is the only genus of this tribe: it is cosmopolitan
in distribution and includes more than 200 species (Noyes,
2003).
Identification - Elasmus is easily
recognizable from other eulophids by having the distinctive characters
mentioned above. Boucek (1988)
and Gibson et al. (1997)
provide keys to distinguish this genus (as the family Elasmidae) from
other chalcidoids. Keys to the species of Elasmus are provided
by Burks (1965) for North America,
by Graham (1995) for Europe,
by Durdyev et al. (1992)
for species living on Lepidoptera in Turkmenia, by Kostjukov
(2000c) for Russia, by Mani
and Saraswat (1972) and Verma
et al. (2002) for India.
Biology – Larvae of most species of
Elasmus are gregarious, primary ectoparasitoids of the larvae
or prepupae of leafmining, leafrolling, web-spinning and casemaking
Lepidoptera. A few species are facultative or obligatory hyperparasitoids
of Lepidoptera, via cocooned prepupae of Braconidae and Ichneumonidae.
A few species are primary ectoparasitoids of Vespidae (Polistes
Latreille) and of leaf-mining Coleoptera (Chrysomelidae: Hispinae)
(Coote, 1997).