Tuesday, February 17, 2009


This specimen was collected in La Verne, CA of Los Angeles County. I was hoping it was a new family for the collection, but it ended up being part of Tenebrionidae, of which I already have one specimen - coincidentally, also of genus Eleodes. Most members of Tenebrionidae do not have hairs, but this specimen and one other of genus Eleodes appear to be covered in setae. This specimen is approximately 15 mm long, and 5 mm wide.

Coleoptera; Polyphaga; Tenebrionoidea; Tenebrionidae; Opatrinae; Eleodes osculans
Common Name: Woolly Darkling Beetle

This specimen is a member of Tenebrionidae, or Darkling beetles. Mealworms are a common larvae for Darkling beetles. Characteristic keying features include 5-5-4 tarsomere configuration and 11-segmented non-clubbed antennae. These insects have sealed elytra and so are incapable of flight, eat decaying and live plant flesh, are not known to bite, and may emit pungent odors. Many have an awkward gait and some lift their pointed abdomen in the air when threatened. This is an extremely common insect family and genus in California.


  1. What does the 5-5-4 tarsomere configuration mean? I thought most beetles onyl had 5 to begin with...

  2. It refers to the number of tarsomeres on the frontal, middle, and hind tarsi. So the front and middle tarsi each have five segments, and the hind tarsus has four segments.