Trypoxylon collinum

Taxonomy

Trypoxylon are square-headed wasps in the family Crabronidae. Trypoxylon is a very diverse genus with 634 species distributed worldwide. At the Minnesota Bee Atlas, we have come across at least two species of palearctic Trypoxylon in our observations. One of those species being the larger and easier-to-identify Trypoxylon collinum.

Description

Trypoxylon collinum are larger species of Trypoxylon with an average length of around 9-10mm. have long abdomens that arc down and are wider at the tip than the base. They have black bodies with a noticeably contrasting band on the second segment of their gaster, ranging from red-orange to orange-yellow in color. Male specimens can be set apart from other species based on very small lobes on the metapleuron and an absence of a spine on the hind tibia.

Nest Structure

Trypoxylon collinum build their nests in cavities left behind by other insects or animals. They have also been shown to nest in larger hollow stems and even openings such as keyholes. In the case of the Minnesota Bee Atlas, they nested in our bee blocks. In each of their nests, T. collinum plug and partition the holes with a chunky mixture of mud and sand. They provision their nests with parasitized spiders.

Hole Sizes

No information at this time 

Voltinism

This species appears to be bivoltine in Minnesota.

Activity

Trypoxylon collinum are most active in Minnesota from June to August.

References

Coville, R. E. 1981. Wasps of the Genus Trypoxylon Subgenus Trypargilum in North America: Hymenoptera, Sphecidae, 1st ed. University of California Press, Oakland.

Sandhouse, G. A. 1940. A review of the Nearctic wasps of the genus Trypoxylon (Hymenoptera: Sphecidae). The American Midland Naturalist, 24(1), 133-176.