Eupelmid Wasps

In many classifications the eupelmids are placed in the family Encyrtidae. However, all the eupelmids agree in possessing an array of characters that indicate that they and the encyrtids diverged separately from the evolutionary stem of the chalcidoids at a remote time in the development of the superfamily. Eupelmids may be recognized by having the margin of the prepectus projecting over the margin of the mesepisternum, in having the forecoxae and midcoxae widely separated, and in having the midcoxae so formed that they can be rotated either anteriorly or posteriorly. The encyrtids do not have those characters.

Several species of Eupelmus have been reared from fruit-infesting Tephritidae, most notably in Europe and Africa. At least two species have been reared from olive fly, Bactrocera oleae (Rossi), and one of these, Eupelmus urozonus Dalman is thought to be exceptionally polyphagous. The biology of E. urozonus is well known. This species has received considerable attention in the olive-growing regions of southern Europe because it is sometimes the most frequently encountered parasitoid of olive fly. Eupelmus urozonus is an ectoparasite, often of late instar larvae and sometimes of pupae. It can also develop as a hyperparasitoid of other olive fly parasitoids.

Female Eupelmidae are readily recognized by the enlarged tibial spur and adjacent basitarsus on the mid leg (Fig. 2) as well as the rounded mesopleuron (Figs. 1, 4). Unlike members of the family Encyrtidae, which also have a rounded mesopleuron, the species of Eupelmus have distinct (usually broad and shallow) notauli. There are always 5 tarsomeres (Fig. 3). Male Eupelmus are difficult to identify, even to family.

Eupelmidae is a family of parasitic wasps in the superfamily Chalcidoidea. The group is apparently polyphyletic, though the different subfamilies may each be monophyletic, and may be elevated to family status in the near future. As presently defined, there are over 905 described species in 45 genera. The larvae of the majority are primary parasitoids, commonly on beetle larvae, though many other hosts are attacked, including spiders, and details of the life history can be variable (e.g., some attack eggs and others are hyperparasites). They are found throughout the world in virtually all habitats.

They are somewhat variable in appearance, though a fair number of species are relatively easy to separate from other Chalcidoidea by the possession of a medially concave mesonotum. They also have the unusual tendency to arch the body strongly upwards when dead, with the head and metasoma often nearly touching above the thorax.

Propelma rohdendorfi holotype in Baltic amber Balcha indica