Dinaraea quadricornis Klimaszewski & Webster

Klimaszewski, Jan, Webster, Reginald P., Langor, David W., Caroline Bourdon, & Jacobs, Jenna, 2013, Review of Canadian species of the genus Dinaraea Thomson, with descriptions of six new species (Coleoptera, Staphylinidae, Aleocharinae, Athetini), ZooKeys 327, pp. 65-101 : 71-73

2. Dinaraea quadricornis Klimaszewski & Webster sp. n. Fig. 2 a–g, Map 2

HOLOTYPE

(male): CANADA, NEW BRUNSWICK, Queens Co., Cambridge, W of Jemseg at "Trout Creek", 45.8227°N, 66.1240°W, 3.VI.2007, R.P. Webster // Silver maple forest, under tight bark of Ulmus americana L. (White elm) (LFC) 1 male. PARATYPES: CANADA, NEW BRUNSWICK: Albert Co., Caledonia Gorge P.N.A., 45.7930°N, 64.7764°W, 1.VII.2011, R.P. Webster // Small rocky clear-cold river (Caledonia Creek), sifting drift material (tree bud material) in eddy area (RWC) 1 male; Albert Co., Caledonia Gorge P.N.A., 45.7941°N, 64.7736°W, 13.IX.2011, R.P. Webster // Near Crooked Creek, mixed forest (red spruce & yellow birch) in decaying mushrooms (NBM) 1 male; Carleton Co., Richmond, Hovey Hill Protected Area, 46.1115°N, 67.7770°W, 24.V.2005, R.P. Webster // Hardwood forest, under bark of beech log (RWC) 1 male; Queens Co., Canning, Grand Lake near Scotchtown, 45.8762°N, 66.1816°W, 30.IV.2006, R.P. Webster // Oak forest, under bark of oak (RWC) 1 female (NBM) 1 female; same locality and habitat data, and collector except 25.V.2006 (RWC) 1 male; Queens Co., Cranberry Lake P.N.A., 46.1125°N, 65.6075°W, 5-11.VI.2009 // R. Webster & M.-A. Giguère, Red oak forest, Lindgren funnel trap (RWC) 1 female; same locality and habitat data, and collectors except 25.VI-1.VII.2009 (RWC) 1 male; Queens Co. Grand Lake Meadows P.N.A., 45.8227°N, 66.1209°W, 17-30.VIII.2011, C. Hughes & R.P. Webster // Old silver maple forest and seasonally flooded marsh, Lindgren funnel trap (NBM) 1 female; Sunbury Co., Lakeville Corner, 45.9007°N, 66.2423°W, 10.IX.2006, R.P. Webster // Silver maple forest, on ridge with oaks, on gilled mushroom (RWC) 1 male; Sunbury Co., Gilbert Island, 45.8769°N, 66.2954°W, 18.VII.2012, C. Hughes & R.P. Webster // Hardwood forest on island, under bark of hardwood (AFC) 1 female York Co., New Maryland, Charters Settlement, 45.8340°N, 66.7450°W, 29.III.2006, R.P. Webster (LFC) 1 female; same locality data except 22.IV.2006, R.P. Webster // Mixed forest in wood pile under bark of spruce (RWC) 1 male; same locality data except 30.IV.2006, R.P. Webster // Mixed forest in wood pile under bark of spruce (RWC) 1 male, 1 female; York Co., New Maryland, Charters Settlement, 45.8331°N, 66.7410°W, 14.IV.2006, R.P. Webster // Mixed forest, under bark of spruce (NBM) 1 female; York Co., New Maryland, Charters Settlement, 45.8404°N, 66.7360°W, 27.V.2008, R.P. Webster // Mixed forest, under bark of spruce (RWC) 1 female.

Etymology.

The specific name quadricornis, means 'with four horns’ in allusion to the four teeth on the male tergite VIII.

Diagnosis.

Dinaraea quadricornis (habitus Fig. 2a) may be distinguished from congeners by the following combination of characters: body length 3.2-3.5 mm; head, pronotum and elytra matte with dense microsculpture; pronotum broadest at middle; elytra at suture as long as pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 strongly transverse; male tergite VIII with four small sharp apical teeth (Fig. 2c); median lobe of aedeagus with straight and short tubus, narrowly rounded apically and slightly produced ventrally (Fig. 2b); spermatheca with pear-shaped capsule and moderately deep apical invagination, stem narrow, long and looped posteriorly, slightly swollen at apex (Fig. 2e).

Description.

Body length 3.2-3.5 mm; body dark brown with legs, antennae (at least basally) and labial palpi yellowish- or reddish-brown; head, pronotum and elytra matte, elytra less so, with dense microsculpture; abdominal microsculpture moderately dense and integument glossy; head about as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest at middle, slightly transverse, as long as elytra at suture; elytra transverse, truncate posteriorly; abdomen arcuate laterally, broadest at middle; male tergite VIII with four small sharp teeth at apical margin (Fig. 2c), sternite VIII slightly produced posteriorly, antecostal suture sinuate (Fig. 2d); median lobe of aedeagus with short and straight tubus, venter of tubus and narrowly rounded apex slightly produced ventrally (Fig. 2b); female tergite VIII slightly sinuate apically on each side of the disc (Fig. 2f), sternite VIII truncate apically, antecostal suture sinuate (Fig. 2g); spermatheca with pear-shaped capsule and moderately deep apical invagination, stem narrow, long and looped posteriorly, slightly swollen at apex (Fig. 2e).

Distribution.

Known only from New Brunswick.

Collection and habitat data.

Adults were collected from March to September in several microhabitats: under tight bark of white elm in a silver maple ( Acer saccharinum L.) forest; in a gilled mushroom located on a ridge with oaks in a silver maple forest; in a hardwood forest with silver maple and butternut ( Juglans cinerea L.); under the bark of a hardwood tree; in a wood pile; under the bark of spruce ( Picea sp.) in a mixed forest; under the bark of a spruce log in an old mixed forest; in a hardwood forest under the bark of a beech ( Fagus grandifolia Ehrh.) log; in decaying mushrooms in a mixed forest with red spruce ( Picea rubens Sarg.) and yellow birch ( Betula alleghaniensis Britt.); and in a red oak ( Quercus rubra L.) forest under the bark of red oak. Flying adults were also captured in Lindgren funnel traps in an old red oak forest and in an old silver maple forest and seasonally flooded marsh. One individual was sifted from drift material (tree buds) in an eddy area along a fast-flowing, clear, cold and rocky river.