How can we assign a BugGuide page to this image when two different species are shown? Not male and female of same species! Please read my commnets below. Thanks.

the side by side image and leave it on the Calosoma page, then link to it.

Btw, yesterday I cleaned off several moldy insects in my collection with ammonia and a small paint brush, and hopefully didn't do too much damage. Thanks for the advice. I'll try EtOH on my moldy leps.

No, don't do EtOH on your leps. That will ruin them. try acetone instead.

same species.

I am 100% sure the one on the right is wilcoxi. Much too small and dark to be scrutator.

I have collected both species during caterpillar outbreaks in forested areas, once in Harrison Co. IN and once in Suffolk Co. NY, and both were present in large numbers on those occasions. The size dimorphism and generally duller appearance of wilcoxi were both conspicuous and constant.

These two species can be superficially distinguished as follows.

Left: almost all are ~ 30 mm long; more color contrast between pronotum and elytra; scape distinctively bulbous (distally swollen) as shown here.

Right: almost all are ~ 20 mm long; less color contrast between pronotum and elytra; scape more cylindrical.

Here's another "scrutator" that was measured at 20 mm, and it seems a bit more colorful than my "wilcoxi." I'm not an expert, so I'd rather not take sides. Would it be possible for me to determine the sex of my two specimens? Does wilcoxi have a more southern distribution?

1) I think that beetle is misidentified. The Dillon and Dillon key separate the two with wilcoxi being 17-20 mm and scrutator being 25-35 mm so the two really don't overlap in size. you might not think 5 mm counts for much but even the smallest 25 mm scrutator will still be MUCH more massive than the biggest 20 mm wilcoxi. I have a lot of experience with both species. In my opinion, you can also separate the two because scrutator always has a bright, shiny, deep purple, porcelain-like pronotum that sharply contrasts with the bright golden margin. Also, the elytra tend to be a brighter golden green with a wider and more brilliant metallic red margin. Wilcoxi is a pretty beetle but just not so vivid; it is darker, duller, and more coppery. The disclaimer would be that old pinned specimens of scrutator can get greasy and faded and become more like wilcoxi but you can fix that with a little xylene.

2) Easy to tell the sexes. I think most carabids share the trait where the males have dilated protarsi. Compare the front legs of this male scrutator with the front legs of this female wilcoxi .

3) wilcoxi does occur in IN. I saw a bunch in late May in South Bend once.

4) I see from you bio that you were at Cornell. I was an entomolgy major there 1986-1990. GO BIG RED!!!

that's why I questioned it's assignment to scruator in the first place. However, I don't know anything about the size difference between males and females of either species, so I will leave it to you pros to hash out.

I was at Cornell in '86 too, so maybe we brushed past each other in Comstock Hall. Wish I could remember my entomology professor's name, but not sure I'd recognize it if I heard it. Twelve years in grad school will do that to ya...

Is there any good way to get some of the mold off my specimens? A fine brush dipped in 10% clorox, perhaps?

using full strength ammonia solution, either brushing lightly or submerging entire specimen for 15 minutes. Never tried 10% clorox. If that fails, clean with Barber's Fluid available at Bioquip.com.

if mold is your only problem then I would just briefly dip the beetle in EtOH. if you've taken the time to spread the legs then this may relax them some but not a huge deal especially if you can get 90% or higher solution that will dry very quickly. I wouldn't use a brush as you'll likely break something. Also wouldn't use the clorox as that will bleach some of the color. If grease is your only problem, then you can just put the whole specimen including the pin and labels (if you used india ink or pencil) in xylene or toluene for a few days and problem solved. That works great for carabids and tiger beetles - nothing more satisfying than seeing those bright white maculations reappear. I don't collect leps. but I've heard that dipping them in acetone for a few minutes will remove mold and grease without matting the scales too much.

based on my discussion above. [Referring to image inserted by Karl Hillig Feb 3, 5:02 PM]