Ant-nest Beetle
Antenna (thin x-section)
Ant-nest Beetle
Maxillary & Labial Palps
Ant-nest Beetle (Arthropterus sp)Class: Animals (Animalia) - Jointed Legs (Arthropoda) - Insects (Insecta)
Order: Beetles (Coleoptera)
Family: Ground Beetle (Carabidae)     iNaturalist Observation
Species: Ant-nest Beetle (Arthropterus sp)
This Photo:     Pincer Mandibles
Other name: Fatihorn Beetle

Thank you Mark Hura for confirming the id of this species for us

General Species Information:
Found on Ellura (in the Murray Mallee, SA) and elsewhere
12-13mm long. A very distinctive honey brown beetle with very wide, thin, antennae.
It also has wide thin legs and elytra (wing covers) that are shorter than the body.
The are 3 pairs of protrusions around it's mouth; pincer like mandibles followed by increasingly larger adaptions (the Maxillary Palps & Labial Palps).
While not seen very often, they are probably a lot more common than the low number sightings suggest. They live in ant nests excreting chemicals that trick the ants into thinking they are queens. As such, the ants actually raise their offspring, all the while the beetle is feasting on the ants.
They are scientifically interesting due to the rapid rate in which they can adapt to new species of ants.
Due to the complex nature of ant pheromones, etc, we can guess that there is a separate species of Arthropterus for each species of ant.
Due to the size of this one, we can guess it's a parasite of Inch ants (Myrmecia sp).

Copyright © 2017-2024 Brett & Marie Smith. All Rights Reserved. Photographed 22-Feb-2017
This species is an Australian Native Species, not listed in the SA Murray Mallee Survey of 2010.