Small Zebra Spider Wasp
S4, Male, dorsal
Small Zebra Spider Wasp
S1, Female, profile
Small Zebra Spider Wasp (Ctenostegus sp)Class: Animals (Animalia) - Jointed Legs (Arthropoda) - Insects (Insecta)
Order: Ant Bee Wasps (Hymenoptera)
Family: Zebra Spider Wasp (Wasp: Pompilidae: Pompilinae)     iNaturalist Observation
Species: Small Zebra Spider Wasp (Ctenostegus sp)
This Photo:     🔍S5, Male, dorsal🔎

Thank you Dr Paul Whitington for confirming the id of this species for us

General Species Information:
Found on Ellura (in the Murray Mallee, SA) and elsewhere
Females & Males are similar size, ~7 to ~10.5mm long (body & head), wingspan ~15mm
Note the stripes are less distinct, more grey than silvery white (compared to the most Turneromyia sp).
The males have quite a different abdomen shape to females, as well as proportionally thicker antennae. Females have 10 flagellomeres & males have 11
Also note the 2 sub-marginal cells on the wing venation; diagnostic for this genus. We first discovered this years ago thru this excellent image by Tony Daley, Insects of Tasmania, showing the wing venation difference between Turneromyia & Ctenostegus: Wing Venation Difference
To our eyes, this looks EXACTLY the same as T. bassiana; but wing venation proves they are different genera.
Paul said "Wing venation is a match to figs.2-12 in Evans, H.E. "A revision of spider wasps of the genus Ctenostegus" Aust.J.Zool. Suppl.Ser. 1976, 43: 1-107. In his paper "A revision of spider wasps of the genus Turneromyia" Aust.J.Zool. Suppl.Ser. 1984, 101: 1-59, Evans states that the distinguishing feature to the closely related pompilid species Turneromyia is the presence of 3 submarginal cells in the forewing of Turneromyia vs. 2 submarginal cells in Ctenostegus."

We have photographed 5 specimens in Jan, Mar, May, Oct & Nov.

Similar Species: Black Sand-dauber Wasp (Crabronidae sp) : Tiny Zebra Spider Wasp (Turneromyia bassiana)

Copyright © 2020-2023 Brett & Marie Smith. All Rights Reserved. Photographed 13-Nov-2020
This species is an Australian Native Species, not listed in the SA Murray Mallee Survey of 2010.