Pink-rimmed Shield Bug
S2 Female, dorsal
Adelaide Hills
Pink-rimmed Shield Bug
S2 Female, profile
 
                      
Pink-rimmed Shield Bug (Diemenia rubromarginata)Class: Animals (Animalia) - Jointed Legs (Arthropoda) - Insects (Insecta)
Order: True Bugs (Hemiptera)
Family: Stink Bug (Pentatomoidea, Pentatomidae)     iNaturalist Observation
Species: Pink-rimmed Shield Bug (Diemenia rubromarginata)
This Photo:     S1 Female, dorsal

Thank you Danilo Lüdke for confirming the id of this species for us

General Species Information:
Found in the Adelaide Hills and possibly elsewhere
~11mm long, which is reasonably small.
Primarily black top & bottom, with a beige to pink rim around the body. The black sometimes protrudes to the outside edge. Here they don't and used to be considered different sub-species where they did.
While they generally have 4 antennae segments, you'll notice one here only has 3 on one and 4 on the other. Normally you'd consider this a loss of one tip, but the remaining tip seems longer and rounded. Possibly a malformed antenna rather than a broken one.
At each antenna base, they have a large hooked spine protruding forward. This is called the "antennophore".
When we saw one on iNat with a strange wing shape, Danilo said "The genus exhibits considerable wing polymorphism. Also thanks to the many users who share their observations in iNat, we now know much more about it. In the past, specimens with distinctive wing differences were actually considered new species, but this soon turned out to be wrong. The distinctive feature is the shape of the pale lobe just in front of the eyes, which fits D. rubromarginata, while in the three other described species it is more or less spinously produced."
An uncommon find. We found two one year in Jan & Feb.

Copyright © 2018-2024 Brett & Marie Smith. All Rights Reserved. Photographed 13-Jan-2018
This species is an Australian Native Species, not listed in the SA Murray Mallee Survey of 2010.