Came to UV light.
I assume this is D. producta because of how long the head is.
However, among the D. producta images in the guide, some specimens (like this one) have roughly a 4:3 ratio of head length to pronotum length, but others (see
http://bugguide.net/node/view/645474, for example) have only slightly more than a 1:1 ratio. I'd be interested to hear from an expert as to whether that's normal variation.