Dyschirioides sellatus
Dyschiriina is a subtribe of carabids that include small, fossorial (they live in tunnels in the soil) members. I found the one above on a river shore in Missouri. I love the interesting form of the beetle, and the delicate amber of the elytra.
Dyschiriines are unusual in that they have odd plate-like sensory structures on the palps (appendages around the mouth). These sensilla differ between males and females, and their function is unknown.
David Maddison
The Subulate Palpomere 
If you visit the Pacific coast of Washington (presumably Oregon too) you will find thousands (so it seems by the number of tunnels in the sand) of Bledius ornatus, and with some patience you can observe the Dyschirius hunting them. The Bledius tunnels have multiple openings so they can get “out the back door” when a Dyschirius comes bursting in through the wall of the tunnel! I know that several species of Dyschirius hunt Bledius sp.; I wonder if this genus does as well?
I would love to see that hunting in action!
The classification of Dyschiriina has changed recently, with Dyschirius sensu Lindroth being split into multiple genera. Dyschirioides is one such. Most North American species are no longer in Dyschirius by that new classification. If the ones on the coast that you mention are the large, rusty-colored ones, then they are now in the genus Akephorus. As far as I know, all of these former-Dyschirius species are Bledius specialists, but it has likely not been studied for D. sellatus.