Epipompilus is a genus of spider wasps in the subfamily Pepsinae, part of the widespread family Pompilidae. Representatives of Epipompilus can be found in Australasia and North and South America.[2] This distribution may indicate that Epipompilus evolved in Gondwana and is similar to other Gondwanan taxa such as the southern beech Nothofagus and Auracaria.
Epipompilus is found in North and South America, ranging from Argentina to extreme southern United States,[3] with around a dozen known species. One species, E. insularis is endemic to New Zealand. In Australia, the genus reaches its greatest diversity, with a greater number of species and a more varied spectrum of morphological features than among the American species. The Epipompilus species in New Guinea are notably brilliantly coloured and apparently highly evolved species. The genus is restricted to these areas but several Tertiaryfossils from the northern hemisphere should probably be placed in Epipompilus.[2]
Ecology and behaviour
These wasps are scarce in collections, probably due to their small size and the fact that they rarely visit flowers. A single male E. turneri which was collected on Leptospermum in New South Wales is one of the few flower records. In Australia observation and collection have often been associated with the trunks of living Eucalyptus trees. The morphology of many of the species suggests that they are adapted for crawling under bark and for entering crevices to search for spiders. Prey recorded includes spiders from the family Sparassidae. These wasps probably do not build nests but hunt spiders underneath bark and lay eggs on them as they find them. Taken into consideration with the many primitive structural features of members of this genus, it is suggestive that the hunting technique of Epipompilus represents an ancestral type of behaviour for spider wasps.[2]
^V.S.L. Pate (1946). "The Generic Names of the Spider Wasps (Psammocharidae olim Pompilidae) and Their Type Species (Hymenoptera: Aculeata)". Transactions of the American Entomological Society. 72 (3): 65–137. JSTOR25077544.
