Taxon classification Animalia Hymenoptera Chalcididae

Megachalcis Cameron, 1903 Figs 165-167, 168

Megachalcis Cameron, 1903: 96-97. Type-species: Megachalcis fumipennis Cameron, 1903, by monotypy.

Allocentrus Cameron, 1911: 12. Type species: Allocentrus hirticeps Cameron, 1911, by monotypy. Synonymised with Megachalcis Cameron by Narendran (1984).

Macrochalcis Masi, 1944: 137. Type species: Macrochalcis bischoffi Masi, 1944, by original designation. Synonymised with Megachalcis Cameron by Narendran (1984).

Diagnosis.

This genus resembles the genus Cratocentrus Cameron in having PMV much longer than MV, T2 to T4 strongly reduced and mostly hidden under the large T1 and in having a long ovipositor sheath. However, it differs from Cratocentrus in having: 1) scapulae and axillae prominently convex (in Cratocentrus scapulae and axillae less convex), and 2) vertex with median raised teeth absent (in Cratocentrus vertex with a pair of raised teeth).

Description.

Body longer than 6 mm; MV much longer than PMV (twice or more); mesonotum with often rasp-like structure; scapulae and axillae prominently convex; propodeal spiracle elongate in oblique subhorizontal direction; body with some silvery patches of setae; petiole very short, mostly concealed in dorsal view; T2 to T4 strongly reduced and for most part hidden under the large T1. Metasoma of ♀ with long ovipositor sheath.

Hosts.

Apparently parasitoid of wood-boring beetles ( Bouček 1988b).

Distribution.

Oriental region.

Key to Vietnamese species of Megachalcis Cameron (based on females)