American Pelecinid Wasp

Appearance

Their antennae are long and the females have an elongated, cylindrical, articulated metasoma. They are parasitoids that lay their eggs directly into grubs of the June beetle buried in the soil. The adults can be found in the late summer.

Naming

Pelecinus polyturator Drury, 1773

Behavior

Female thrusts its long abdomen and ovipositor into soil to detect host (beetle grubs), lays one egg on each. Pelecinid larva burrows into the beetle larva, killing it. Wasp larva scavenges remains and pupates there in soil.

Some populations of Pelecinus polyturator are parthenogenic; females do not require fertilization by males to reproduce. Females are common throughout its range, but males are rare in the United States and Canada especially in some populations, and more common farther south.

Reproduction

Parasitoids of insect larvae that feed on decomposing wood, etc. These include larvae of scarab beetles, esp. May Beetles (Phyllophaga). Also reported to parasitize wood-boring insects. Female thrusts its long abdomen and ovipositor into soil to detect host, lays one egg on each. Pelecinid larva burrows into the beetle larva, killing it. Wasp larva scavenges remains and pupates there in soil.

Males are scarce in general, but their scarcity is more pronounced in certain populations, that are suspected to be parthenogenetic.

Food

Larvae eat beetle grubs. Adults feed on nectar.

Evolution

May be a complex of species. A number of color variants have been described, especially in the tropics, but most sources say that the family is represented by a single species north of Mexico.