Moved from Bembidiini.

Moved from Pericompsus ephippiatus.

Thanks for straightening these out for me. I'll leave this one at the tribe level for now and try to further determine under the scope.

Opinion of Dr. Makarov: this is Tachys or Paratachys, while Pericompsus has strongly punctate striae (see here)

Moved from Bembidiini.

Moved from Trechinae.

with a good key and a little magnification, this one keyed directly to Pericompsus ephippiatus (Say). There are two large "pits" below the mentum central tooth (just visible in my ventral photo) that separate this from several other genera. And the presence of 6 elytra stria (not well seen in my photo, but confirmed under magnification) leads to Pericompsus.

From Downie and Arnett this is the only species of the genus in the northeast (with a distro including the south and central states). "A common species along the banks of streams" (nearest stream is 0.5miles from me, although there are several ditches closer).

I couldn't find any web images to help confirm, but the other genus members from the MCZ's type photos look close.

Another new genus and species for BugGuide :)

Moved from Ground Beetles.

Trech*us- or Tach*ys genus group (difficult both, you´d need to count and localise setae and punctures).