Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Calendar

TaxonomyBrowseInfoImagesLinksBooksData
Photo#101036
ground beetle - Polyderis laeva

ground beetle - Polyderis laeva
Lynnfield, Essex County, Massachusetts, USA
April 1, 2007
Size: 1.5mm

Polyderis laevis
It sure fits the description, especially the small size, and it looks just like the picture. Thanks Tim!

Trechinae, Bembidiini, Elaphropus?
. . . can´t be much else, being so small.

 
Polyderis?
What do you think about Polyderis? I flipped through Downie and Arnett for the Bembidiini tribe, and while size is not the best criteria, the smallest 2 Elaphropus listed are 1.9mm-2.5mm, and they are both described as dark brown.
Conversly, Polyderis laevis (only NAmer species) is described as "1.2-1.5mm, piceous to brown, elytra truncate at apex, striae faint, smooth, only sutural one impressed, #8 barely present at apex", and "Our smallest carabid"! And it's listed occurring in Mass and throughout Eastern NAmerica (specifically including Mass). Once again the Canada Carabid site provides a photo here

what do you think?

Comment viewing options
Select your preferred way to display the comments and click 'Save settings' to activate your changes.