Quedius (Microsaurus) bicoloris Smetana & Webster 2011

Head, pronotum, and scutellum black. Elytra rusty red. First two and basal half of third visible abdominal tergites or first three visible tergites entirely piceous black to black, remainder of abdominal tergites rusty red to pale reddish. Mandibles piceous black to black, maxillary and labial palpi testaceous. Antennae piceous, becoming gradually variably paler toward apex. Legs piceous, with dorsal faces of front tibiae and all tarsi variably paler. Head of rounded quadrangular shape, wider than long (ratio 1.21), usually slightly widened behind eyes, posterior angles obsolete; eyes rather small, feebly convex, tempora somewhat longer than eyes seen from above (ratio 1.20); no additional setiferous punctures between anterior frontal punctures; posterior frontal puncture shifted markedly posteriad, situated close to posterior margin of head, two punctures between it and posterior margin of head (one of these punctures missing unilaterally in some specimens); temporal puncture shifted posteriad, separated from posteriomedial margin of eye by distance about twice as long as its distance from posterior margin of head; surface of head with very fine, very dense microsculpture of transverse and oblique waves, with intermixed fine micropunctulae that become gradually coarser toward posterior portions of head. Antennae short, moderately widened toward apex, segments 2 and 3 subequal in length, segments 4 and 5 about as long as wide, segments 6 to 10 wider than long, gradually becoming shorter, with segments 9 and 10 markedly transverse, last segment about as long as two preceding segments combined. Pronotum wider than long (ratio 1.15), widest at about posterior third, narrowed anteriad, with lateral margins continuously arcuate with broadly rounded base, transversely convex, lateral portions not explanate; dorsal rows each with only one puncture at anterior pronotal margin (puncture occasionally doubled unilaterally); sublateral rows each with one puncture close to anterior margin of pronotum; microsculpture similar to that on head, but slightly denser, intermixed micropunctulae quite fine. Scutellum impunctate, surface with microsculpture of very fine waves. Elytra moderately long, at base narrower than pronotum at widest point, no more than vaguely dilated posteriad, at suture as long as, at sides somewhat longer than pronotum at midline (ratio 1.14); punctation dual, consisting of moderately coarse and very fine punctures; coarser punctures on each elytron forming a group on medial half of elytral base laterad of scutellum and from there extending in a sparse, very variable, unstable erratic pattern posteriad toward posterior margin of each elytron; irregular row of coarser punctures present along suture of each elytron and on margin of elytra; very fine punctures present in irregular, variable pattern on entire surface of each elytron, including lateral portion; surface between punctures without appreciable microsculpture. Wings fully developed. Abdomen with tergite 7 (fifth visible) with fine whitish apical seam of palisade setae; tergite 2 (in front of fully visible tergite 3) impunctate (some micropunctulae present); punctation of abdominal tergites dense at base of each tergite, becoming sparser toward apex of each tergite, and in general toward apex of abdomen; pubescence piceous; surface between punctures with exceedingly fine microsculpture of broken striae.

Quedius bicoloris is distributed in northeastern North America (Map 1). It is presently known from New Brunswick, Ontario, and Quebec in Canada and, so far, only from New Hampshire in the United States. It is expected to be more widely distributed.