Description & Statistics

Pelecinidae. -- These wasps parasitize the larvae of Phyllophaga spp. (Coleoptera: Scarabaeidae) There are three species known in one genus (Pelecinus), which are distributed in the Western Hemisphere. There is only one North American genus with one species: Pelecinus polyturator Drury. Worldwide, there is only one extant genus, Pelecinus, with three recognized species (Galloway 2008):

By 1940 only fragmentary information was available on biology and behavior of this family (Clausen 1940). Pelecinus polyturator Drury was studied in North America. Adult females were 2-3 in. in length and had long slender abdomens, which in flight was carried in a characteristic curved position. The male was of normal form with a club shaped abdomen.

Parasitization of scarabaeid larvae by P. polyturator was first observed by Forbes (1889) and other researchers since have reported rearings from similar hosts. Sometimes the host had attained the pupal stage before death. Development is internal, and pupation occurs outside the host body. However, the habitat of adult females is not that in which grubs of the phytophagous Scarabaeidae are usually found. They are usually associated with trees and are particularly abundant in areas where trees have been cut. Clausen (1940) thought it probable that the true hosts were coleopterous larvae living in decaying wood and that the attack on scarabaeid larvae may be incidental. Adults appear in the field during July to September, and there was thought to be a single generation. In North America males of P. polyturator are very rare, suggesting that reproduction was by thelytoky. Numerous males, however, represent Neotropical varieties in collections and these seem to represent geographical strains where reproduction is bisexual (Brues 1928).

In Pelecinidae the body is black and at least 20 mm long, (Masner 1993). The forewing has a forked Rs vein. The female metasoma is long and thin, the male metasoma shorter and pedunculate with metasomal segment 1 made into a petiole.

The pelecinid Pelecinus polyturator (Drury) parasitizes grubs of Phyllophaga (Coleoptera: Scarabaeidae) by probing its metasoma into the soil to reach the host. Females are abundant in late summer, but males are difficult to find. The family occurs only in the Western Hemisphere (Canada to Argentina), but one extinct genus has been identified from Oligocene Baltic amber (Masner 1993).

References: Please refer to <biology.ref.htm>, [Additional references may be found at: MELVYL Library]

Masner, L. 1993. Chapter 13, Superfamily Proctotrupoidea, p. 537. In: Goulet, H. & J. T. Huber (eds.), Hymenoptera of the World: An Identification Guide to Families. Research Branch, Agr. Canada, Publ. 1894/E. 668 p.

Masner, L. 1993. Chapter 14, Superfamily Platygastroidea, p. 558-565. In: Goulet, H. & J. T. Huber (eds.), Hymenoptera of the World: An Identification Guide to Families. Research Branch, Agr. Canada, Publ. 1894/E. 668 p.

Masner, L. 1993. Chapter 15, Superfamily Ceraphronoidea, p. 566-569. In: Goulet, H. & J. T. Huber (eds.), Hymenoptera of the World: An Identification Guide to Families. Research Branch, Agr. Canada, Publ. 1894/E. 668 p.