Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
small carabid - Polyderis laeva

small carabid - Polyderis laeva
Wayland, Middlesex County, Massachusetts, USA
April 17, 2008
Size: 1.5mm

Moved from Trechinae.

Thanks Brad
It's not the best picture. It's tiny, and it wouldn't stop moving, even after chilling.

Trechinae I think. Drawing a blank on it though.

Subfamily Trechinae covers several genera
of which Trechus spp. in my area all have well-defined elytral striations and they are 3-4 mm or larger. If body size "1.5 mm" is accurate and elytra are indeed smooth, I would favor genus Polyderis, despite this image appearing much darker than my specimens of P. laevis. There is a slim chance this could even be a tiny Acupalpus. Unfortunately there is not enough photographic detail to see the palps, supraorbital setae, and recurrent sutural striae - all important features for tribe placement.

this is P. laevis indeed
(see MCZ holotypus of Bembidion laevum Say)