Hymenoptera

Pigeon tremex look like long, cylindrical wasps. The thorax is reddish-brown and the abdomen is marked with yellow and black bands. The wings vary from golden brown to black. The adults of both sexes have pointed appendages at the end of the abdomen. The females also have a long, slender egg-laying organ, called an ovipositor. The adults are from 2.5 to 5 cm long, with the females slightly larger than the males.

The white larvae, 5 cm long, have light brown heads and a black spine at the tip of the abdomen. Their legs are relatively undeveloped.

These wasps are black with yellow spots. They have a narrow waist (pedicel) about the same length as the rest of the abdomen. They range in total length from 24 to 28 mm. 

These insects come in widely varying sizes (10 to 55 mm long), but all have an elongated abdomen attached to the thorax by a characteristic “thread-waisted” long, narrow, petiole-shaped structure. They may be entirely black or brown or dark with white, yellow or red markings. The females’ forelegs often have specialized structures for digging.

The larvae are pale coloured and legless. 

In the past, the Sphecid family included the Crabronidae [lien], a fairly similar-looking group of wasps that now forms a separate family. 

These insects look like large, slender wasps. They have a yellow head with a dark stripe between the eyes. The thorax and abdomen are dark, either black or dark brown. Their long legs are mainly yellow, while their four elongated, narrow wings are almost black.

Females have an impressive 12- to 15-cm long dark brown ovipositor.

This species resembles two other ichneumons found in the same habitat in Quebec: Megarhyssa macrurus and M. greenei. Giant ichneumons are recognizable by their blackish-brown abdomens. In addition, they have the longest ovipositors.

These black wasps have greenish-yellow bands on their abdomens. Their legs are yellow, except for the parts nearest their bodies. Their wings are transparent, with brown veins. They are 13 to 16 mm long.