Size: 8-9.8mm

Seasonality: most active along the coastline of California from March through September, further south, inland, seasonality tends to be prolonged due to warmer weather.

Distribution; CA, s. OR, w. NV, Baja California Norte-MX

Information: often found under stones and pieces of wood near rivers or ponds. They are very common in the correct locations. Large piece of wood or rocks may have many individuals taking cover under them at once. They take cover during the day and emerge at night to hunt around the water's edge. 

Description: body: elongate, semi-ovate, moderately robust; flattish. Dorsal colouration matte blue-grey, ventral faces and legs black. Head elongate-triangular, slender; base of the head constricted into a slight neck. Face long; mandibles longish, curved at the tips, partially obscured by the labrum. Eyes do not strongly bulge laterally; two supraorbital setae over each eye. Antennae dark, antennal pubescence begins on the second antennomere following the pedicel (segment 3). Pronotum smallish, semi-quadrate; anterior margin transverse; anterior angles acute, jutting forward slightly; lateral margins strongly sinuate; hind angles squarish; basal margin nearly transverse, weakly rounded. Margins thinly beaded; disk lined by faint wrinkles, mostly smooth, with a large, rough depression on either side of the lower median bulge. Scutellum exposed; laterobasal ridges entire, sinuate. 9 well-defined striae per elytron, intervals flattish. Three small setigerous pores may be found along the 3rd elytral stria. Humeral shoulders obtuse, rounded; lateral margins rounded, elongate; apices weakly sinuate.