Chlaenius tricolor vigilans
Chlaenius tricolor vigilans
Size: 10-12mm
Seasonality: April-November
Distribution; BC, WA, OR, CA, NV, w.UT, w.AZ
Information: though often found along waterways and lakes, the species may also be found among leaf litter in forested areas. Due to intraspecific variation within the subspecies, the pronotum shape tends to vary from one locale to the next, without any particular pattern. Nocturnal, attracted to UV and mercury vapour traps, predatory. See two dorsal photos at the bottom of the page, and the dorsal studio shot to the right of species information.
Description: body: elongate-ovate, somewhat slender. Dorsal colouration: pronota bright green, bronze, or pinkish-bronze; elytra dark or lighter blue; legs orange. Head triangular; surface of the head smooth, with sparse micropuncturing; two thin, shallow dimples on the frons, which do not continue onto the clypeus. Clypeus mostly smooth, rectangular; labrum semi-opaque orange, rectangular, with roughly the same dimensions as the clypeus. Mandibles dark orange, inner margin black; mandibles strongly curved into points. Lower mouth parts pale to dark yellow-orange. First three antennal segments (scapus, pedicel, first following antennomere) pale yellow-orange, the rest of the antennal segments should be dark. Pale antennal pubescence begins on the second antennomere following the pedicel (segment 4). Eyes not reduced in size; the males of this subspecies often have eyes which bulge laterally stronger than on the females; some individuals have a few very shallow wrinkles over their eyes. Pronotum hexagonal; anterior margin transverse; anterior angles obtuse; lateral margins rounded, with a weak angle at the lateral median; lateral margins thinly beaded; hind angles obtuse; basal margin weakly sinuous. Pronotal disk flattish, though the anterior region should be somewhat convex; disk very heavily coated in small setigerous punctures; median line absent or faint; lower median bulge varies in strength; either side of the lower median bulge should have a short, slender indent located within a shallow depression. Scutellum exposed. 9 well-defined, thinly-pitted striae per elytron, strial pits around the scutellum should be slightly larger, intervals flattish. Elytra fully pubescent; pubescence pale, white or pale grey. Humeral shoulders rounded-obtuse; lateral margins rounded, elongate, nearly parallel; apices rounded, either weakly or strongly sinuate.