Searcher - Calosoma sayi

Calosoma sayi

Lynette, this is a Calosoma. Looking at the full-size image, I can see the orange dots characteristic of (mostly) that genus. I don't think any of our Carabus have such punctures. I believe I can also see the morphology of the antennae that differentiate Calosoma from Carabus--see the guide page for genus Calosoma.

It looks like C. sayi, which is common, if not downright abundant, in our area.

Patrick Coin
Durham, North Carolina

… Cotinis, 29 October, 2005 - 6:54am

Thanks

I agree I also see the orange spots. If that's characteristic of the Calosoma, I'll move it there.

… Lynette Elliott, 29 October, 2005 - 9:44am

C. sayi, I think!

Yes, looking at Ciegler, (1) seems that only Calosoma have those colored punctures (foveae) and among them, only C. calidum, C. frigidum, and C. sayi have those in NC. Brimley (2) notes frigidum and calidum only from the mountains. Of course, that is an old reference, but the taxonomy seems to have stayed constant, more or less, in that genus, and those are big beetles, favorites of collectors.

Hmm. Crossing my fingers, compare the pronotum of what I believe to be C. sayi:

The only other Calosoma I think I've seen is C. externum, which has a rather different pronotum. See the comments and thumbnails in that linked image. Also, I'm looking at the relative abundance in the NCSU collection and statements of collection locales in Brimley (2) above. They all seem to indicate C. sayi is the most common in our area, and likely the only one with those colorful punctures. I think that is what we are both seeing. I'm always ready to stand corrected. Carabids are tough. Next time I find one of these, I am going to be sure to capture and photograph the underside, some of Ciegler's (1) keys refer to the underside. I might even have some photos of the underside I haven't posted.

Feeling my way towards knowledge, or ignorance, as always...

Patrick Coin
Durham, North Carolina

… Cotinis, 29 October, 2005 - 10:56am

Carabus cancellatus, perhaps

A rather small genus, only 5 spp. in Carolinas--see print and Internet references in guide page. Using Ciegler(1), Ground Beetles of South Carolina: C. vinctus I know, it has distinctive interrupted elytral ridges. Other species, except C. cancellatus, have blue margins to elytra. This one appears to be all blackish above. So perhaps it is C. cancellatus.

One has to watch Calosoma--they are very similar to Carabus. I don't think this is C. sayi, which is pretty black above. Have to watch that--compare to my photos of that species.

Yours doesn't appear to have the coppery spots of C. sayi. Most of the other Calosoma have shiny green elytra.

Knowing the size would be helpful, if known fairly precisely.

Patrick Coin
Durham, North Carolina

… Cotinis, 1 March, 2005 - 10:17pm

Size an unreliable character.

I have seen some relatively tiny Calosoma, and some pretty large Carabus. It is a tough call separating them without seeing the specimen.

… Eric R. Eaton, 2 March, 2005 - 11:52am

hmmm

If I remember right...the size would not be easily calculated as these beetles are quite fast runners! I sent this beetle's photo off to Paul Choate listed as Carabus and he didn't argue....so I am assuming that is his approval.

… Lynette Elliott, 2 March, 2005 - 6:27am

Carabus serratus?

I agree with Carabus. This looks like Carabus serratus to me but they always have blue elytral margins.

… Frank Guarnieri, 28 October, 2005 - 10:39pm