Nebria arkansana
Nebria arkansana
Size: 8.4-11mm
Seasonality: May-September
Distribution; AB, BC, YT, ID, MT, NV, OR, WA, WY.
Information: n/a
Description: body: elongate-oblong, semi-ovate, slender. Dorsal and ventral colouration fully ventral. Head triangular; surface of the head mostly smooth, frons transversely wrinkled: shallow. Two faint dimples may be found on the frons, which do not continue onto the clypeus. Clypeus mostly smooth, front margin dorsally wrinkled. Labrum rectangular, short; front margin wavy. Mandibledlongish, strongly curved on the front half. Palpi dark piceous. Antennae black, some specimens may have a slight brownish hue to the lower segments. The first antennomere following the pedicel should be noticably longate than the scapus; the next antennomere following that should be about the length of the scapus, followed by another as long as the first after the pedicel. Antennal pubescence begins on the third antennomere following the pedicel. Eyes strognly bulging laterally, but slightly reduced in size. Pronotum slender, cordate; front margin curved inward, with a small angle at the median; front angles acute, jutting forward; lateral margins beaded, sinuous; hind angles acute; base weakly sinuous, nearly straight. Pronotal base slightly narrower than the humeral shoulders. Median line short, but strong; the centre of the disk on either side of the median should be smooth, elevated; the dorsal lateral, front, and basal margins should be depressed, rough. Dorsal base riddled with heavy micro-wrinkles. Elytra elongate-ovate, nearly oblong, slender; 8 well-defined striae per elytron, intervals weakly elevated, flat near the apices. Interval 3 should have five small setigerous pits touching the 3rd stria: scattered along the entire length of the interval. Humeral shoulders obtuse-rounded, sloping towards the apices; lateral margins nearly straight, slightly bulging outward just before the apices; apices weakly sinuate.