Evagetes crassicornis is a kleptoparasitic spider wasp with a holarctic distribution.

A red and black spider hunting wasp[2] with fairly short and thick antennae with well-developed sensory powers which it uses to identify the nests of other spider wasps and tarsal combs on the forelegs for digging into these nests.

[3] In Great Britain and Ireland the flight period is May to September.

E. crassicornis spends a lot of time searching for the nests of its host species on open sunny ground.

[3] Adult E. crassicornis visit a wide variety of open flowers which have short corollae, especially Apiaceae and Asteraceae.