Review of Canadian species of the genus Dinaraea Thomson, with descriptions of six new species (Coleoptera, Staphylinidae, Aleocharinae, Athetini)

Abstract Twelve species of the genus Dinaraea Thomson are recognized in the Nearctic region, ten of which occur in Canada, all east of the Rocky Mountains. Six species are herein described as new to science: Dinaraea bicornis Klimaszewski & Webster, sp. n.; Dinaraea curtipenis Klimaszewski & Webster, sp. n.; Dinaraea longipenis Klimaszewski & Webster, sp. n.; Dinaraea quadricornis Klimaszewski & Webster, sp. n.; Dinaraea worki Klimaszewski & Jacobs, sp. n.; and Dinaraea piceana Klimaszewski & Jacobs, sp. n. Four formerly described species are confirmed in Canada: Dinaraea angustula (Thomson), Dinaraea backusensis Klimaszewski & Brunke, Dinaraea borealis Lohse, and Dinaraea pacei Klimaszewki & Langor. The previously unknown male of Dinaraea borealis Lohse and female of Dinaraea backusensis are described. All species are illustrated with colour habitus images and black and white images of the median lobe of the aedeagus and spermatheca, and tergite VIII and sternite VIII of both sexes. New habitat and distribution data are presented and a key to all Nearctic species of the genus is provided.

rected posteriad in apical two-thirds, anteriad in basal third, and laterad at sides; elytra short, at suture as long as pronotum or only slightly longer; abdominal tergites 3-5 each with distinct basal impression; tarsal formula 4-5-5; male tergite VIII in majority of species with small teeth at apical margin and sometimes also in adjacent area of disc; median lobe of aedeagus with athetine bridge and of a simple form, with inconspicuous structures of internal sac; spermatheca with conical capsule and long slim stem coiled posteriorly.
Comments. Based on the morphology of the male tergite VIII, two groups of species are recognized. One group, consisting of the majority of species, is characterized by tergite VIII bearing two-to-several small teeth on the apical margin. Species in the second group (D. borealis, D. curtipenis, D. longipenis, D. planaris, D. subdepressa), have tergite VIII truncate and without teeth on the apical margin.
Biology. Many species are known from the subcortical galleries of other insects but their diet is unknown.

1
Elytra at suture shorter than pronotum (Figs 1a, 4a, 10a Pronotum trapezoidal in shape, broadest in apical third, punctures very dense, pronotum appearing matte (Fig. 1a); male tergite VIII with two teeth (Fig. 1c); median lobe of aedeagus and spermatheca as illustrated (Fig. 1b Pronotum rectangular in shape, broadest at middle, punctures very dense (pronotum appearing matte) and distanced from each other by a diameter of a puncture (Fig. 2a); male tergite VIII, median lobe of aedeagus, and spermatheca as illustrated ( Fig. 2c,  Body dark brown with reddish tinge (Fig. 8a); tubus of median lobe of aedeagus long and straight ventrally, and with narrow sclerites of internal sac (Fig. 8b); spermatheca as illustrated (Fig. 8e)  Pronotum dark brown and elytra yellowish-brown (Fig. 5a); male tergite VIII, median lobe of aedeagus and spermatheca as illustrated (Fig. 5b,  Median lobe of aedeagus with tubus slightly sinuate apically and slightly produced ventrally at apex, internal sac structures short and straight (Fig. 13a); male tergite VIII without apical teeth (Fig. 13b), sternite VIII as illustrated (Fig. 13c) Lohse and Smetana (1985), there are no major external differences between the two species and they key to the same couplet. Etymology. The specific name bicornis means 'with two horns' in allusion to the two teeth on the male tergite VIII.
Description. Body length 3.1-3.4 mm; body dark brown with at least posterior part of elytra paler, with legs, antennae and labial palpi yellowish-brown; head and pronotum with dense microsculpture and appearing matte; elytral and particularly pronotal microsculpture less dense and their integument appears glossy; head about as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest in apical third, slightly transverse, longer than elytra at suture; elytra transverse, shorter than pronotum at suture, truncate posteriorly; abdomen arcuate laterally, broadest in apical third; male tergite VIII with two small sharp medial teeth at apical margin ( Fig.  1c), sternite VIII slightly produced posteriorly, antecostal suture arcuate (Fig. 1d); median lobe of aedeagus with short and straight venter of tubus and narrowly rounded apex (Fig. 1b); female tergite VIII slightly sinuate apically on each side of disc ( Fig. 1f), sternite VIII rounded apically, antecostal suture sinuate (Fig. 1g); spermatheca with pear-shaped capsule and moderately deep apical invagination, stem narrow, long and looped posteriorly, slightly swollen at apex (Fig. 1e).
Distribution. Known from New Brunswick and Ontario. Collection and habitat data. Most adults were collected in April and May, and one specimen in October. The New Brunswick specimens were found in moss and leaf litter near the edges of small vernal pools in forests containing eastern white cedar (Thuja occidentalis L.) and red maple (Acer rubrum L.), and sometimes alder and poplar.  Etymology. The specific name quadricornis, means 'with four horns' in allusion to the four teeth on the male tergite VIII.

Dinaraea quadricornis
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).
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. Diagnosis. Dinaraea backusensis (habitus Fig. 3a) may be distinguished from congeners by the following combination of characters: body length 2.4-2.6 mm; head, pronotum and elytra moderately glossy with dense microsculpture; pronotum broadest in about apical third and narrowest at base; elytra at suture as long as pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 moderately transverse; male tergite VIII with four small apical median teeth, median ones rounded (Fig. 3d); median lobe of aedeagus with straight and short tubus, narrowly rounded apically (Fig. 3b, h); spermatheca with large pear-shaped capsule and moderately shallow apical invagination, stem moderately long and looped posteriorly, apical end strongly swollen (Fig. 3c).
Distribution. Known from Ontario and New Brunswick in Canada and Massachusetts in the USA. Collection and habitat data. Adults were collected from March to August mostly from under the bark of rotting logs (spruce, maples) in a variety of hardwood and mixed hardwood-conifer forest types. Some adults were found in polypore fungi on a large fallen basswood (Tilia americana L.) and in moss and litter at the base of cedar in an old-growth eastern white cedar swamp. Flying adults were also captured in Lindgren funnel traps in a red spruce forest with red maple and balsam fir (Abies balsamea (L.) Mill.) and in an old red pine (Pinus resinosa Ait.) forest.
Material  Etymology. Named for Dr. Timothy Work, Université du Québec à Montréal, Quebec, Canada, who provided many insect specimens for this study and who has advanced the ecological knowledge of epigaeic beetles in Canada.

Dinaraea worki
Diagnosis. Dinaraea worki (habitus Fig. 4a) may be distinguished from congeners by the following combination of characters: body length 2.3-2.6 mm; head, pronotum and elytra moderately glossy with moderately dense microsculpture; pronotum broadest in middle and narrowest at base; 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 apical teeth, all short and rounded (Fig. 4c); median lobe of aedeagus with straight and short tubus narrowly rounded apically (Fig. 4b); spermatheca with large pear-shaped capsule and long apical invagination, stem short and looped posteriorly, with slightly swollen apical part (Fig. 4e).
Description. Body length 2.3-2.6 mm; body dark brown with legs, antennae (at least basally), labial palpi and posterior part of elytra yellowish-or reddish-brown; head, pronotum and elytra moderately glossy, with moderately dense microsculpture; abdominal microsculpture moderately dense and integument more glossy; head about as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest in middle, slightly transverse, about as long as elytra at suture; elytra transverse, truncate posteriorly; abdomen arcuate laterally, broadest in middle; male tergite VIII with four small rounded teeth at apical margin (Fig. 4c), sternite VIII rounded posteriorly, antecostal suture arcuate and anterior margin broadly arcuate (Fig. 4d); median lobe of aedeagus with short and straight venter of tubus and narrowly rounded apex (Fig. 4b); female tergite VIII slightly sinuate apically on each side of disc (Fig. 4f), sternite VIII rounded apically, antecostal suture sinuate (Fig. 4g); spermatheca with large pear-shaped capsule, and long apical invagination, stem short and looped posteriorly, with slightly swollen apical part (Fig. 4e).

Distribution. Known from Quebec.
Collection and habitat data. Several adults were collected in November. Specimens from western Quebec were collected from dead and decaying black spruce (Picea mariana Mill. (BSP)) in a boreal forest dominated by black spruce. Diagnosis. Dinaraea piceana (habitus Fig. 5a) may be distinguished from congeners by the following combination of characters: body length 3.1-3.3 mm; head, pronotum and elytra matte with dense microsculpture; pronotum broadest in apical third and narrowest at base; elytra at suture slightly longer than pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 moderately transverse; male tergite VIII with four small apical teeth, all short and rounded (Fig. 5c); median lobe of aedeagus with straight and short tubus narrowly rounded apically and slightly produced ventrally (Fig. 5b); spermatheca with elongate pear-shaped capsule, and moderately long apical invagination, stem long, sinuate and looped posteriorly, with slightly larger apical part (Fig. 5e).
Distribution. Known from Quebec. Collection and habitat data. Most adults were collected in dead black spruce logs in boreal black spruce forests, and one was captured in an intercept trap in a boreal forest during July.
Description. Body length 3.3-3.7 mm; body dark brown with legs, antennae (at least basally), labial palpi and elytra yellowish-or reddish-brown, pronotum and abdomen lighter than head, sometimes entire body appears brown; head, pronotum and elytra slightly glossy, with dense microsculpture; abdominal microsculpture less dense and integument more glossy than that of pronotum and elytra; head about as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest at middle, slightly transverse, usually longer than elytra at suture; elytra transverse, truncate posteriorly; abdomen subparallel; male tergite VIII with four small apical teeth, all short and rounded and some additional tooth-like subapical structures (Fig.  6c), sternite VIII produced apically (Fig. 6d); median lobe of aedeagus with short and straight venter of tubus and narrowly ventrally pointed apex (Fig. 6b); female tergite VIII concave basally and truncate apically (Fig. 6f), sternite VIII rounded apically and emarginated medially, antecostal suture slightly sinuate (Fig. 6g); spermatheca with short pear-shaped capsule, and small apical invagination, stem long, straight medially and looped posteriorly, with slightly swollen apical part (Fig. 6e).
Distribution. This Palaearctic species is adventive in North America . The earliest Canadian records are: Elora, Ontario in 1975 (DEBU); St. Andrews, New Brunswick in 1978 (DEBU); Fairview, Alberta in 1982 (DEBU). The first North American records are: Buffalo and New York before 1889 (Fauvel 1889); Davis, California before 1984 (Muona 1984). In Canada, the species is known from Newfoundland and Labrador, Nova Scotia, Prince Edward Island, New Brunswick, Quebec, Ontario, Alberta and Yukon Territory (Klimaszewski et al. 2007, 2010, 2011, 2012, Majka and Klimaszewski 2008, Webster et al. 2009). In the USA, it is reported from New York, Pennsylvania and California, but is likely more widely distributed in the northeastern states.
Collection and habitat data. In North America, this species is associated with soil and organic debris in agricultural fields and disturbed urban meadows. It is also found in marsh litter, in leaf litter in mixed forests, in compost, under bark of decaying spruce logs, amongst vegetation on a coastal sand dune, in litter in a cattail marsh, in Diagnosis. Dinaraea pacei (habitus Fig. 7a) may be distinguished from congeners by the following combination of characters: body length 2.2-2.5 mm; head, pronotum and elytra slightly glossy with dense microsculpture; pronotum broadest in apical third and narrowest at base; elytra at suture slightly longer than pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 moderately transverse; male tergite VIII with four minute apical teeth, all short and rounded, and scarcely visible (Fig. 7c); median lobe of aedeagus with strongly produced ventrally and narrowly rounded apically tubus (Fig. 7b); spermatheca with short pear-shaped capsule, and small apical invagination, stem short and looped posteriorly, with slightly swollen apical part (Fig. 7e). Dinaraea pacei is not distinguishable externally from Dinaraea subdepressa (Bernhauer), which was described from New Hampshire. However, the two species can be readily separated by the structures of the internal sac of the median lobe. The internal sac of D. subdepressa has two simple, straight, narrowly elongate sclerites (Fig. 13a), while the sclerites of D. pacei are complex as illustrated in Fig. 7b. The apical part of the median lobe is straight and slightly produced ventrally at the apex in D. subdepressa (Fig. 13a), while it is sinuate and strongly produced ventrally in D. pacei (Fig. 7b). The two species apparently represent sister taxa.
Description. Body length 2.2-2.5 mm; body dark brown with legs, antennae (at least basally), labial palpi and elytra slightly paler and appearing reddish-brown, pronotum and abdomen lighter than head, sometimes entire body appears brown; head, pronotum and elytra slightly glossy, with dense microsculpture; abdominal microsculpture less dense and integument more glossy than pronotum and elytra; head about as large and broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest in apical third, slightly transverse, usually shorter than elytra at suture; elytra transverse, truncate posteriorly; abdomen subparallel; male tergite VIII with four minute apical teeth, all short and rounded, and scarcely visible (Fig. 7c); sternite VIII arcuate apically (Fig. 7d); median lobe of aedeagus with short and sinuate tubus and narrowly dorsally pointed apex (Fig. 7b); female tergite VIII concave basally and truncate apically (Fig. 7f), sternite VIII rounded apically and emarginated medially, antecostal suture slightly sinuate (Fig. 7g); spermatheca with short pear-shaped capsule, and small apical invagination, stem short and looped posteriorly, with slightly swollen apical part (Fig. 7e).
Distribution. This species was previously recorded only from southwest Labrador ). Here, we provide new distribution data from British Columbia, New Brunswick, Quebec and Alaska.
Collection and habitat data. Adults in Newfoundland and Labrador were collected from June to August using pitfall traps and flight intercept traps in various coniferous forest types, and one specimen was collected under the bark of a dead red pine . In British Columbia, adults were caught in July and September in emergence traps attached to the trunks of lodgepole pine (Pinus contorta Dougl. ex Loud. latifolia Engelm.) infested by mountain pine beetle (Dendroctonus ponderosae Hopkins). In New Brunswick, adults were found: under the bark of large fallen spruce in an old-growth eastern white cedar swamp; under tight bark of American elm; in a silver maple forest; in fleshy polypore fungi at the base of a dead standing Populus sp. in a wet alder swamp; and in a group of Pholiota sp. at the base of a dead Populus sp. in a mixed forest. In Quebec, adults were found in dead black spruce in a black spruce forest. Adults were also captured in Lindgren funnel traps deployed in an old-growth white spruce (Picea glauca (Moench) Voss) and balsam fir forest, an old mixed forest with red and white spruce, red and white pine (Pinus strobus L.), and a rich Appalachian hardwood forest with some conifers. Adults were collected from March to September. Dinaraea borealis Lohse, in Lohse et al. 1990: 198 (based on a single female description). HOLOTYPE (female): CANADA, QUEBEC, Gt. Whale River, 30.VI.1949, J.R. Vockeroth, No. 20341 (CNC). Holotype examined.
Diagnosis. Dinaraea borealis (habitus Fig. 8a) may be distinguished from congeners by the following combination of characters: body length 2.8-3.0 mm; head, pronotum and elytra slightly glossy with dense microsculpture; pronotum broadest in apical third and narrowest at base; elytra at suture as long as pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 moderately transverse; male tergite VIII without apical teeth (Fig. 8c); median lobe of aedeagus with straight, long tubus pointed at apex and slightly pointed ventrally (Fig. 8b); spermatheca elongate with pear-shaped capsule, and long apical invagination, stem long and looped posteriorly, with strongly swollen apical part (Fig. 8e).
Description. Body length 2.8-3.0 mm; body variable in colour, either entirely black with brown or reddish appendages and part of elytra, or dark brown with legs,  Etymology. Curtipenis means 'possessing a short penis', in allusion to the short tubus of the median lobe of the aedeagus in this species.
Diagnosis. Dinaraea curtipenis (habitus Fig. 9a) may be distinguished from congeners by the following combination of characters: body length 3.0 mm; head, pronotum and elytra slightly glossy with dense microsculpture and bluish tinge; pronotum broadest in the middle and narrowest at base; elytra at suture as long as pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 moderately transverse; male tergite VIII without apical teeth (Fig. 9c); median lobe of aedeagus with straight, short tubus pointed at apex and slightly pointed ventrally (Fig. 9d), internal sac with distinct sclerites (Fig. 9b). Dinaraea curtipenis is superficially similar to D. subdipressa but can be distinguished from it by lacking a strongly depressed posterior edge of pronotum, while it is strongly depressed at the posterior angle of the disc and medially at base forming a groove in the latter species; and it has more elongate bulbus of median lobe of aedeagus with additional dorsal and ventral sclerotized structures (Fig. 9b).
Description. Body length 3.0 mm; body dark brown with reddish-brown tarsi, tibia and bases of antennae; head, pronotum and elytra slightly glossy, elytra more so, with dense microsculpture; abdominal microsculpture less dense and integument more glossy than that of pronotum and elytra; head large, as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest in middle, slightly transverse, usually as long as elytra at suture; elytra transverse, truncate posteriorly; abdomen subparallel; male tergite VIII truncate apically and without apical teeth (Fig.  9c); sternite VIII rounded apically (Fig. 9d); median lobe of aedeagus with short and straight tubus with apex pointed ventrally (Fig. 9b). Female undescribed. FEMALE. We have several females from New Brunswick localities found without male association that may belong to this species but because they are very similar externally and have similar genitalia to those of D. pacei we hesitate to formally associate them with D. curtipenis. These females have a more coarsely punctate pronotum than those of D. pacei but have similar rounded posterior angles of pronotum. We anticipate that this problem will be solved by finding females associated with males at the same locality. Distribution. This species is known only from New Brunswick. Collection and habitat data. The holotype was collected from under the bark of a conifer log in a mixed forest. Other individuals were captured in Lindgren funnel traps in an old red oak forest, an old-growth eastern white cedar forest, an old-growth white spruce and balsam fir forest, and old red pine forests. The paratype was collected from a well-decayed and fungus-covered log in a mixed forest. Adults were collected during May and July. Etymology. Longipenis means 'possessing a long penis', in allusion to the long tubus of the median lobe of the aedeagus in this species.

Dinaraea longipenis
Diagnosis. Dinaraea longipenis (habitus Fig. 10a) may be distinguished from congeners by the following combination of characters: body length 3.5 mm; head, pronotum and elytra slightly glossy with dense microsculpture; pronotum broadest in the middle and narrowest at base; elytra at suture shorter than pronotum, with dense punctation similar to that on pronotum; antennal articles 7-10 strongly transverse; male tergite VIII without apical teeth (Fig. 10c); median lobe of aedeagus with straight, long tubus rounded at apex and slightly pointed ventrally (Fig. 10b), internal sac with thin sclerites (Fig. 10b). FEMALE: We have one female from New Brunswick found without male association that may belong to this species. This female is externally very similar to the male of D. longipenis but the spermatheca and tergite and sternite VIII are indistinguishable from that of D. piceana. We need more specimens of this species, with male and female association, to confirm and formally describe the female of this species.
Description. Body length 3.5 mm; body dark black with light reddish-brown tarsi, tibia and bases of antennae; head, pronotum and elytra slightly glossy, the elytra more so, with dense microsculpture; abdominal microsculpture less dense and integument more glossy than that of pronotum and elytra; head large, about as broad as pronotum, genae slightly longer than eyes in dorsal view; pronotum broadest in middle, slightly transverse, longer than elytra at suture; elytra transverse, truncate posteriorly; abdomen arcuate laterally; male tergite VIII truncate apically and without apical teeth, slightly angular laterally at apical margin (Fig.  10c), sternite VIII rounded apically (Fig. 10d); median lobe of aedeagus with long and straight tubus with apex rounded and pointed ventrally (Fig. 10b). Female undescribed (see above).
Distribution. This species is known only from New Brunswick.
Collection and habitat data. The holotype was captured during May in a Carex marsh by treading emergent vegetation. The paratype was collected from a well-rotted log in a hardwood forest. son, Katie Burgess, Marie-Andrée Giguère, Cory Hughes, Colin MacKay, Michelle Roy, and Vincent Webster for technical assistance and collecting specimens; Natural Resources Canada -Canadian Forest Service, Canadian Food Inspection Agency, and USDA APHIS for funding the study on early detection of invasive cerambycids, which provided many specimens collected in Lindgren funnel traps; the Canadian Wildlife Service for funding insect surveys at the Shepody National Wildlife Area; the New Brunswick Wildlife Trust Fund for funding various insect surveys over the past 7 years; the Meduxnekeag River Association for permission to sample beetles at the Meduxnekeag Valley Nature Preserve (which includes the Bell Forest); and New Brunswick Department of Natural Resources (Fish and Wildlife Branch) for issuing permits for sampling in the Protected Natural Areas and for providing logistical support. Survey work in the Jacquet River Gorge Protected Natural Area and the Caledonia Gorge Protected Area was organized through the New Brunswick Museum with external funding from the New Brunswick Environmental Trust Fund, Salamander Foundation, and the New Brunswick Wildlife Trust Fund. We appreciate the assistance of James Hammond (NoFC) in drafting the distribution maps, Pamela Cheers (LFC) in editing and Diane Paquet (LFC) in formatting the manuscript. This project was financed by the Canadian Forest Service, Natural Resources Canada.