11 replies to this topic

[dspdrew]

1. Location of collection: Trabuco Canyon, California.
2. Date of collection:  4-27-2015.
3. Habitat of collection:  Chaparral, oak forest.
4. Length (from head to gaster):  7.5 mm.
5. Color, hue, pattern and texture:  All brown.
6. Distinguishing characteristics: Hairier than most Crematogaster I have seen. Relatively small gaster and large head.
7. Anything else distinctive: I found three of these, and all three looked this way.
8. Nest description:

 

 

 

[dspdrew]

I usually don't post Crematogaster ID request threads because of how hard the California species are to tell apart, but these looked unique enough that I decided to post it.

 

If I was to go by AntWeb, my best guess would probably be C. californica.

[Gregory2455]

Why do you even bother with this drew? Haha. Crematogaster are impossible but good luck.

[dspdrew]

I know, but I explained why.

[Gregory2455]

I know, but I explained why.

I know but still.

[Alza]

What is that round thing on its head used for ?

[cpman]

That is an ocellus, and it is used to sense light.

[Gregory2455]

Drew, these were the ones that "look parasitic", right?

[dspdrew]

Yes. I caught tons of them last week. A few of them have removed their wings this time, so we'll see what happens.

[dspdrew]

James C. Trager, mentioned somewhere else, that this might be Crematogaster mutans which is thought to be parasitic. After reading about them, I would totally agree.
 

The females of mutans can be easily separated from all other North American species by the very long, silky, yellowish, appressed pubescence, the compressed thorax, depressed gaster, and proportionately very large head.

This species in the female has a very large head, and the least voluminous thorax and gaster of any North American species known to me. The habitus is thus much like a dulqtic species. As temporary social parasitic species are known in the genus Crematogaster, the discovery of another would not be too surprising. If this new species is a temporary parasite the host must be either Crematogaster californica or Crematogaster mormonum or both, to my knowledge the only other ground nesting species occurring with any commonness in the foot-hills and lower mountains of California and western Nevada. Unfortunately, mixed incipient colonies, if they exist, have not yet been found. (Buren 1968)

The queens are also described as being 8mm in length.

[JWRay]

Any chance you have gotten your hands on the generic revision of North American species from 2009?  Its a PhD Dissertation from UTEP.

[dspdrew]

Nope. Not I.