A worldwide community photographing and learning about wildlife
Project Noah Nature School
Aulacocyclus edentulus
Under a large rotting eucalyptus log. Each adult beetle was about 35mm long. Larvae were slightly longer. One adult was black and the other was a red-brown but otherwise they appeared identical from above. ?
Under timber in suburban back yard.
This spotting is possible evidence that this species might show variable colours? Random or sexual dimorphism?
Two important ID features here are split elytra (flight capable) and a short, grooved, upward curved, blunt facial horn.
family: PASSALIDAE
subfamily: Aulacocyclinae
genus: Aulacocyclus
http://bie.ala.org.au/species/urn:lsid:b...
Also this is a great page of inputs re Bess beetles vs. 'Horned passalids" http://www.whatsthatbug.com/category/bee...
Spotted on Sep 29, 2013
Submitted on Sep 29, 2013
5 Comments
You are welcome Mark.
All I did was just reply to your comment on my spotting :-)
Thanks Chun and Tamara for making me research this properly. It has an ID.
Thanks for the input Tamara. It's certainly not easy to find accurate information online about these even though many people know them.
My son loves these beetles and has studied them for several years. We believe the reddish brown "Bessies" are immature adults, and darken to black as they mature.
Passalids definitely look alike all around the world.
You are lucky to get both colors in one spotting.