Need help with a beetle ID
I came across this beetle today at Cockroach Bay preserve which is part of Tampa Bay. The reserve is near Ruskin, Florida and the beetle was in a very sandy area with some scrub grassland with intermintent wildflowers and weeds. I know much more about birds and butterflies…but from what I could gather this may be some sort of stag beetle? It was good sized…maybe 1.5 inches in length or so. Any input on this beetle would be great!
Colin Gjervold
Sarasota, FL

Dear Colin,
I must confess I am intrigued by a place called Cockroach Bay and I’m not entirely sure I want to visit it. Your photo, on the other hand, is a new one for us. We checked with our expert at the Natural History Museum in Los Angeles, Weiping, who writes: “Sorry to answer you so late. I took yesterday off for vacation. This image is not a Dorcus parallelus. You can see five tarsi on the hind leg. I am sure it is belonging to Carabus sp. (Coleoptera: Carabidae), probably from Asia..”
Ed. Note:
(09/06/2004) Eric, another of our beetle experts, just wrote in saying: “The Carabus sp. from Cockroach Bay, FL is actually a species of Pasimachus. Neat!”
Since we always defer to more knowledgeable experts, we will include both possibilities.

Update: (08/22/2006)
Hello Lisa Anne and Daniel, I recently came across your website and I was pleased to see such a vibrant (and well-done) site. I’m an entomologist and evolutionary biologist (specializing on the systematics, taxonomy and evolution of tiger beetles and their close relatives) and I have to say that I’m impressed with your accuracy rate! It’s much, much better than other comparable sites I’ve come across over the years. The two of you must really love insects. In any case, I noticed that you are open to information from specialists, so I thought I’d give you a few ID’s of species that I came across on your pages. I was having trouble sleeping, so I went through all of the tiger beetles, scaratines, etc and checked them out. Here you go: I’ll bookmark your site and check it out when I’m having trouble sleeping again!
“Pasimachus possibly, or Carabus species (02/29/2004) Need help with a beetle ID” This is most definitely a Pasimachus! (you can omit the exclamation point and the following if you want to print this, but that beetle is unequivocally a Pasimachus, not a Carabus. Those two genera are very easy to separate from even a photograph on the basic of many characters such as antennal length and form, head width and shape, mandible length/shape, pronotal shape, etc.) It is Pasimachus marginatus at that, a lovely species found in Florida and other parts of the Southeast.
Daniel P. Duran
Dept. of Biological Sciences
Vanderbilt University
Nashville, TN

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