Two new species and new provincial records of aleocharine rove beetles from Newfoundland and Labrador, Canada (Coleoptera, Staphylinidae, Aleocharinae)

Abstract Two new species, Atheta pseudovestita Klimaszewski & Langor, sp. n., Silusa prettyae Klimaszewski & Langor, sp. n., are described, and 16 new provincial records, including one new country record, of aleocharine beetles are presented for the province of Newfoundland and Labrador. Diagnostics, images of habitus and genital structures, distribution, bionomics information and new locality data are provided for the newly recorded species. A new checklist with 189 species of aleocharines recorded from the province is presented.


Introduction
In the first comprehensive survey of the Aleocharinae fauna of Newfoundland and Labrador (NL), 172 species in 47 genera and 12 tribes were reported (Klimaszewski et al. 2011). Since this treatment of aleocharine beetles, new specimens have become available for study resulting in the discovery of additional species. Klimaszewski et al. (2015a) published a study of Canadian and Alaskan Clusiota Casey and subgenus Microdota Mulsant & Rey of Atheta Thomson with new records of adventive Palaearctic Atheta (Microdota) subtils Scriba from Labrador and New Brunswick. They removed Atheta (Microdota) pratensis (Mäklin) from the Newfoundland list of species on the basis of misidentification. The present, updated list of aleocharines from Newfoundland stands at 189 (Table 1). In this contribution, two species new to science and 16 new provincial records, including one new country record, are provided. As well, an updated checklist of all species from the province is provided (Table 1).

Materials and methods
All specimens in this study were dissected to examine the genital structures. Extracted genital structures were dehydrated in absolute alcohol, mounted in Canada balsam on celluloid micro-slides, and pinned with the specimens from which they originated. Images of the entire body and the genital structures were taken using an image processing system (Nikon SMZ 1500 stereoscopic microscope; Nikon Digital Camera DXM 1200F, and Adobe Photoshop software).
Morphological terminology mainly follows that used by Seevers (1978) and Klimaszewski et al. (2011). The ventral side of the median lobe of the aedeagus is considered to be the side of the bulbus containing the foramen mediale, the entrance of the ductus ejaculatorius, and the adjacent ventral side of the tubus of the median lobe with the internal sac and its structures (this part is referred to as the parameral side in some recent publications); the opposite side is referred to as the dorsal side. In the species descriptions, microsculpture refers to the surface of the upper forebody (head, pronotum and elytra).

Discussion
Of the 189 species currently known from NL, 31 are adventive, 17 Holarctic, and 141 are Nearctic. The high percentage (16.4%) of adventive species is not surprising because NL was one of the first Canadian provinces with well-established trade with Europe dating back to the 17th century. Genera with the highest number of adventive species are Aleochara (5 spp.) and Atheta (5 spp.), and the tribe Athetini (15 spp., including 5 Atheta spp.), which contains the majority of aleocharine species. The relatively high percentage of Holarctic species (8.9%) found in NL is due to the distribution of some Holarctic species at higher latitudes in both North America and Europe (e.g., Gnypeta, many Philhygra, and some Atheta). Detailed provincial faunal surveys provide a clear and comprehensive biodiversity dataset to establish baseline biodiversity composition where ecosystems are undergoing rapid change due to anthropogenic disturbances and climate change. Species from this family and subfamily are known to be exceptionally good ecological indicators and are increasingly being used to assess ecosystem resistance and resilience in the wake of development and environmental changes (Pohl et al. 2007. This paper contributes to improving baseline knowledge of the Aleocharinae in the province of NL. The extensive sampling efforts for insects in the province to date have resulted in 189 known aleocharine species. Undoubtedly, more will be discovered over time with additional sampling and further taxonomic study. However, we believe that due to intensive sampling efforts in NF and LB conducted in recent years (Langor in Klimaszewski et al. 2011), the vast majority of the most common and widely distributed species are now known, so new future additions to the fauna will likely be species associated with rare or poorly sampled microhabitats. As well, the subarctic and arctic northern part of Labrador is poorly sampled but likely contains yet-unrecorded species from the province. Diagnosis. Body length 3.0-6.5 mm, piceous-to-black, with tarsi, last articles of labial and maxillary palpi and often posterior margin of elytra rust-brown ( Fig. 1). This species is externally very similar to A. lanuginosa Gravenhorst from which it differs by the shape of the sclerites of the internal sac of the aedeagus (Fig. 2), the shape of the spermatheca (Fig. 7), and the smooth apical margin of male tergite VIII (Fig. 3). For a more detailed description, see Klimaszewski (1984).  Klimaszewski 1984, Klimaszewski and Cervenka 1986, Gouix and Klimaszewski 2007, Bousquet et al. 2013 Bionomics. In Newfoundland, adults were collected in moose dung near a bog, and in bear and sheep/horse dung. In New Brunswick, adults were captured from fresh moose dung in an eastern white cedar swamp and in decaying sea wrack resting on vegetation on the upper margin of a salt marsh ). The adults were collected from May to July.

Aleochara (Aleochara) tahoensis Casey Figs 8-14
Diagnosis. Body length 4.5-7.0 mm, robust, dark brown to black, with legs, labial and maxillary palpi and most of elytra (except for scutellar section) rust-brown (Fig. 8); maximum distance between eyes equal to 2.5 times maximum diameter of eye (Fig. 8). This species is externally very similar to A. gracilicornis Bernhauer from which it differs by having a wider distance between eyes (2.0 times maximum diameter of eye in A. gracilicornis). It may be distinguished from all species of Aleochara by the shape of median lobe and the sclerites of the internal sac of the aedeagus (Fig. 9), and the shape of the spermatheca (Fig. 14). For a more detailed description, see Klimaszewski (1984).  References Klimaszewski 1984, Gouix and Klimaszewski 2007, Majka and Klimaszewski 2010, Bousquet et al. 2013 Bionomics. In Newfoundland, adults were collected from among beach rocks and detritus. Elsewhere, adults were captured from flood debris, swampy areas, debris around dead elm and from a moose carcass (Klimaszewski 1984). Most specimens collected in southwestern USA were found at high altitudes up to 2438 m. The adults were collected from May to September.

Aleochara (Aleochara) gracilicornis Bernhauer Figs 15-22
Diagnosis. Body length 4.0-6.0 mm, robust, dark brown to black, with legs or only tarsi, labial and maxillary palpi and most of elytra (except sides and for scutellar section) rust-brown to yellowish-brown (Fig. 15); maximum distance between eyes equal to 2.0 times maximum diameter of eye (Fig. 15). This species is externally very similar to A. tahoensis Bernhauer from which it differs by having a narrower distance between eyes (2.5 times maximum diameter of eye in A. tahoensis). It may be distinguished from all species of Aleochara by the shape of the median lobe and the sclerites of the internal sac of the aedeagus (Fig. 16), and the shape of the spermatheca (Fig. 22). For a more detailed description, see Klimaszewski (1984).
Distribution.  Klimaszewski 1984, Gouix and Klimaszewski 2007, Bousquet et al. 2013 Bionomics. In North America, adults were collected from debris among vegetation in a temporary creek, from leaves and debris at the edge of deciduous forest and from flood debris, in swampy habitats, and in an old beaver lodge and on carrion (Klimaszewski 1984). Specimens were collected from March to September at altitudes up to 2651 m.

Ilyobates bennetti Donistorphe Figs 23-30
Diagnosis. This species is easily distinguishable from other aleocharines by its distinctive body shape, integument with coarse and dense punctation and pubescence (Fig.  23), and the genital structures (Figs 24,25,30). Body colour is reddish to almost black. Distribution.
Bionomics. In Newfoundland, specimens were captured in mixed boreal forest using pitfall traps. In New Brunswick, this adventive species was collected in litter at the base of a tree in a silver maple swamp, in flood debris along a river margin, and among decaying corncobs and cornhusks near a home in a forested residential area ). Majka and Klimaszewski (2008) reported this species from pitfall traps in pastures and a blueberry field in Nova Scotia. In Europe, this species has been reported from similar habitats (Assing 1999). Adults were collected from June to August.
Comments. This adventive species is well established in eastern Canada. ( Diagnosis. This species is easily recognized to genus by the shape of its habitus with subparallel body, deeply impressed and coarsely punctate first three visible abdominal tergites, elongate pronotum, very long tarsi with hind tarsi almost as long as tibia (Fig.  31), and the shape of spermatheca (Figs 34). The only other known Nearctic species, P. fuliginosa (Casey), is darker, with a slightly shorter and more densely punctate pronotum, and has quadrate to slightly transverse antennomeres VIII-X (see Fig. 28 in Klimaszewski et al. 2011).

Distribution.
Origin Nearctic Distribution Canada: NF, ON; USA: NY New records New provincial record; NEWFOUNDLAND: Glide Lake, 8-IX-1993, pitfall 3.8 (MUN) 1 female. References Casey 1906, Moore and Legner 1975, Seevers 1978, Ashe 2000 Bionomics. In Newfoundland, one female was captured in a pitfall trap in September from a coniferous forest. In Ontario, females of P. americana were found on a stream bank and in a dry stream bed under a rock .
Comments. This is the second record of this species from Canada, and it is much further east than the first record from Ontario by Brunke et al. (2012). We expect P. americana to occur broadly over northeastern North America in riparian habitats. At both Canadian localities only females were captured, and the original description is also based on a female specimen captured in Peekskill, New York (Casey 1906).
Diagnosis. This species is easily distinguishable from other aleocharines by its small (1.8-3.4 mm) and elongate body (Fig. 35), small eyes, and distinctive genitalia (42)(43). Head and abdomen, except for the posterior margins of the segments and the apex, dark brown to blackish; pronotum brown to dark brown; elytra yellowish-brown to brown; legs yellowish; antennae yellowish to yellowish-brown, or rarely the whole body may be considerably darker or paler (Fig. 35). For a more detailed description, see Assing and Wunderle (2008)  Bionomics. Alevonota gracilenta apparently prefers a wide range of unforested habitats in its native range, but is usually only collected in small numbers and using passive traps (Assing and Wunderle 2008). It was suggested that known specimens represent dispersing individuals and that the real habitat preferences of this species re- main unknown, but are possibly subterranean (Assing and Wunderle 2008). In Newfoundland, one male was captured in an agricultural field in July. In New Brunswick, specimens were captured in Lindgren funnel traps in hardwood forests, a mixed forest, and an old white pine (Pinus strobus L.) stand. In southern Ontario, specimens were captured in pitfall traps in soybean fields and hedgerows . Adults were captured in Canada from May to July.
Comments. The accidental introduction of this obscure Palaearctic species into North America is surprising and may be recent as all known first discovered specimens are from 2009-2010 from two contiguous counties in southern Ontario . The presence of this uncommon species in New Brunswick and Newfoundland suggests that it may have been introduced into Canada earlier than previously thought and had been missed due to a lack of adequate sampling in the Atlantic Provinces (Webster et al. 2016). A specimen from Colorado, identified as Alevonota by G.A. Lohse, is deposited in the CNC (A. Davies, personal communication) and study of this specimen may reveal that native Alevonota species occur in North America .
Distribution. Bionomics. In Newfoundland, one female was collected in a pitfall trap in a mixed boreal forest in July. In New Brunswick, Atheta giguereae was found in mature and oldgrowth eastern white cedar swamps, a mixed forest, an old-growth northern hardwood forest, and an old white pine stand (Webster et al. 2016). Adults were sifted from moss and leaf litter near streams and brooks and from moist moss in these forests (Webster et al. 2016). A few individuals were captured in Lindgren funnel traps. Specimens from Nova Scotia were captured in flight intercept traps in red spruce and red sprucehemlock forests (Webster et al. 2016). Adults were collected from April to August. Diagnosis. Atheta klagesi is very similar to A. pseudoklagesi, and may be distinguished from it by the following combination of characters: body slightly smaller in size and more glossy, yellowish spots on elytra more intense, more intense yellowish colouration of legs, bases of antennae and maxillary palps and overall more contrasting body colour (Fig. 52); median lobe of aedeagus has shorter tubus and a more arcuate and slightly differently shaped apex (Figs 53, 54); spermatheca (Fig. 60) is very similarly shaped in both species and females may be difficult to identify unless collected with males.

Distribution.
Bionomics. In Newfoundland, adults were collected in pitfall traps in boreal conifer forests in July and August.
Comments. See comments under the next species.

Atheta (Pseudota) pseudoklagesi Klimaszewski & Webster Figs 61-68
Diagnosis. This is a sibling species of A. klagesi and was previously confused with the latter in collections. It may be distinguished from A. klagesi by its slightly larger size, less glossy body, less intense yellowish colouration of spots on elytra, legs, bases of antennae and maxillary palps, and overall less contrasting body colour (Fig. 61); median lobe of aedeagus has longer tubus and slightly different shape of apex in lateral view (Fig. 62); spermatheca (Fig. 68) is very similarly shaped in both species and females may be difficult to identify without accompanying males.  Webster et al. 2016 Bionomics. In Newfoundland, adults were collected in pitfall traps in boreal forests in July and August. In New Brunswick, adults of this species were found in mature mixed forest, old-growth and old white spruce and balsam fir forests, a mature red spruce forest, and in a wet alder swamp. Specimens were collected from coral fungi on a Populus log, fleshy polypore fungi at base of a dead standing Populus, in decaying gilled mushrooms, in gilled mushrooms, and under bark of red spruce (Webster et al. 2016). Adults were collected from May to September.
Comments. In the past, the two sibling species were mixed together and identified as A. klagesi. All material across Canada and the USA needs to be re-examined for understanding the true distribution of the two species. In this paper, only Newfoundland and New Brunswick specimens were re-evaluated (Webster et al. 2016).  Diagnosis. Body length 3.5-3.9 mm; body moderately narrow (Fig. 69); head, antennal articles III-XI, pronotum, base of elytra, and abdomen dark brown, but legs and posterior part of elytra paler, yellowish to rust-brown; integument moderately glossy (more so than in A. vestita), sparsely punctate and pubescent, pubescence short and adhering to the body, with dense meshed microsculpture, denser on forebody, sculpticells hexagonal; head round, about as wide and as long as pronotum, with eyes shorter than postocular area; antennae with articles I-V elongate and VI-X subquadrate to slightly transverse (Fig. 69); pronotum margined laterally, trapezoidal in form in dorsal view, narrowest at base, widening apically to about apical third and then abruptly narrowed apically, slightly transverse, much narrower at base than elytra; elytra flattened, slightly longer than pronotum; abdomen broad, slightly swollen medially. MALE. Median lobe of aedeagus with narrowly oval bulbus streamlined with tubus in dorsal view (Fig. 71); in lateral view tubus arcuate ventrally and with broadly triangular apex (Fig. 70); internal sac structures not pronounced (Figs 70,71); tergite VIII truncate apically and without teeth (Fig. 72); sternite VIII elongate, broadly rounded apically (Fig. 73). FEMALE. Tergite VIII broadly rounded apically (Fig. 74); sternite VIII truncate apically and slightly emarginated medially (Fig. 75); spermatheca with short capsule bearing wide and relatively deep apical invagination, stem sinuate, bent subapically and sinuate at apex (Fig. 76).
Bionomics. This species was found in Newfoundland under detritus along seashore, under seaweed on sandy beaches, in vegetation and gravel on riverbanks, and on the edge of a marsh very close to a shoreline. Adults were collected in June.
Comments. This species is very similar externally to a Palaearctic adventive species found in NB, NS and NF. Both species may be mixed up in collections. Atheta pseudovesita may be distinguished from A. vestita by the following combination of characters: body distinctly more glossy, colouration darker and predominantly dark brown (light brown in A. vestita), pubescence on forebody sparser and punctation more distinct, tergites and sternites VIII similar in both species, median lobe of aedeagus narrowly elongate apically in A. vestita (Fig. 304b in Klimaszewski et al. 2011) and broadly triangular in A. pseudovestita (Fig. 62); spermatheca of a completely different form, with stem bent and subparallel at 2/3 of its length and with slightly twisted subapical section (Fig. 68), while spermatheca is S-shaped in A. vestita (Fig. 304c in Klimaszewski et al. 2011). Apparently the two species represent sibling species. For distribution, description and illustrations of A. vestita, see Klimaszewski et al. 2007Klimaszewski et al. , 2011.  Bionomics. The Newfoundland females were captured using pitfall traps in agricultural fields in 2007. In Ontario, specimens were collected in agricultural hedgerows using pitfall traps in 2009 and 2010 . Adults were collected in May and June.

Callicerus rigidicornis (Erichson)
Comments. Callicerus rigidicornis was recorded from North America as an adventive species for the first time based on Ontario specimens collected in agricultural hedgerows ). The NL record may suggest a broader distribution of this adventive species in Canada, but it is unknown whether these records represent separate introduction events. For information on natural history of this species in Europe, see .
Distribution. Bionomics. In Newfoundland, one female was captured in a pitfall trap in a boreal conifer forest. Most adults from Quebec were collected in yellow birch-and balsam fir-dominated forest using pitfall traps ). In New Brunswick, adults were found: under decaying seaweed on a coastal beach; under driftwood on a riverbank; in grass, moss and leaf litter near water and in alder and cedar swamps and Carex marshes; in Sphagnum moss and leaf litter in a young regenerating mixedwood forest; and in other decaying material in forests. In Ontario, adults were captured in litter around raspberry near a bog, in a Typha marsh, and in a nest of Microtus pennsylvanicus . Adults were active from March to October in Canada. In Minnesota, adults were captured on a lakeshore and in a Microtus nest, and in Indiana were taken by sifting dump vegetable debris from March to November .
Comments. This species is probably more widely distributed in Newfoundland than the single record suggests.

Mocyta sphagnorum Klimaszewski & Webster Figs 93-100
Diagnosis. This species may be distinguishable from other Mocyta species by its large and dark brown to black pronotum, elytra about as long as pronotum (Figs 93,94), shape of apical structures of the internal sac of the aedeagus (Fig. 95), and shape of the spermatheca (Fig. 100). For a more detailed description, see Klimaszewski et al. 2015c.
Distribution.  Klimaszewski et al. 2015c Bionomics. In Newfoundland, adults were collected in pitfall traps in boreal mixedwood and conifer forests and from under seashore detritus. In New Brunswick, adults were found in sphagnum moss and litter in calcareous eastern white cedar fens, in a black spruce forest, and one individual was collected from moldy conifer duff at the base of a large pine in a mixed forest (Klimaszewski et al. 2015). Adults were found in April and May in New Brunswick, and June to August elsewhere.

Origin
Comments. This species is probably more widely distributed in the boreal forest of Canada. Some specimens from Cheeseman Provincial Park are tentatively associated with this species because the antecostal suture of female sternite VIII was not straight like in typical forms but was strongly sinuate medially. These specimens were excluded from M. fungi (Gravenhorst) because of the short elytra, about as long as the pronotum, while the elytra are longer than the pronotum in M. fungi.

Stethusa spuriella (Casey) Figs 101-108
Atheta (Stethusa) spuriella Casey, 1910: 8. As Stethusa: Gusarov 2003bBrunke et al. 2012: 181. Diagnosis. This species may be distinguishable from two other Nearctic Stethusa species by the following combination of characters (Gusarov 2003b): Stethusa spuriella differs from S. dichroa (Gravenhorst) in a smaller body size (length 2.1-2.5 mm), the lack of sub-basal impressions of the terminal antennal article (Fig. 101), the lack of the distal spines of the internal sac (Figs 102, 103); the shape of the spermatheca (Fig. 108); and the lack of a female accessory sclerite. Stethusa spuriella differs from S. klimschi (Bernhauer) in having a smaller body size, the bent apex of the median lobe in lateral view (Fig. 102), and a shorter spermatheca (Fig. 108).  Casey 1910, Gusarov 2003b Bionomics. In Newfoundland, one female was captured in a pitfall trap in mixed forest. In Ontario, Stethusa spuriella appears to be a common species in both forested and open habitats, some specimens were captured on fungi . Adults were collected from May to August.

Origin
Comments. This species probably reaches its northernmost distribution limit in Newfoundland.
Diagnosis. This species may be distinguishable from two other similar Nearctic species of Philhygra by the following combination of characters: body length 3.4 mm; body narrow with subparallel sides; antennae, head, pronotum, and abdomen dark brown, legs and elytra yellowish-brown (Fig. 109); integument not glossy; forebody with minute and dense punctation and dense pubescence (Fig. 109); head rounded posterolaterally, with large eyes; antenna with articles V-X slightly elongate to subquadrate (Fig. 109); pronotum rounded anteriorly and angular postero-laterally, transverse, slightly wider than head and slightly narrower than elytra, pubescence directed laterad on arcuate lines from midline of disc (Fig. 109); elytra slightly transverse, with pubescence directed postero-laterad and forming waves; abdomen subparallel, narrower than elytra. Median lobe of aedeagus and terminal abdominal structures as illustrated (Figs 110-115). For more details, see Webster et al. 2016. Reference Webster et al. 2016 Bionomics. In Newfoundland, specimens were found in gravel and moss on a riverbank, under seaweed on a sandy beach, and by sweeping vegetation in riparian habitat. In New Brunswick, P. hygrotopora were found in moss near the splash zone of a waterfall, in gravel on the margin of a shaded spring-fed brook near a waterfall, among gravel on a gravel bar along a shaded brook in a northern hardwood forest, and in gravel along a cold shaded brook. A few individuals were found under decaying seaweed on a sea beach. Adults were collected during June, July, August, and September. Etymology. This species is named after Andrea Pretty, an enthusiastic entomophilic park interpreter who collected the type series in Butterpot Provincial Park.
Distribution. Known only from Butterpot Provincial Park in southeastern Newfoundland, Canada.
Bionomics. Adults were collected in August and September in pitfall traps in coniferous boreal forest.
Comments. This species is very similar externally to S. californica Bernhauer but may be separated from it by: its smaller body with shorter elytra (elytra at suture about as long as pronotum along median line); light brown colour with darker antennae, head, and posterior elytra and abdomen; and differently shaped spermatheca in lateral view (Fig. 123). The male of this species is similar to that of S. californica Bernhauer but the apical half of the tubus of the aedeagus is produced ventrally at about 75% angle and in S. californica at about 90% angle. The female spermatheca is distinct in its shape and has the best diagnostic features for this species (Fig. 123), and this is also the reason why the female was designated for a holotype. For illustrations of S. californica, see Klimaszewski et al. (2003). The three European species, S. rubiginosa (Er.), S. rubra (Er.), and S. pipitzi Epph., are ruled out as conspecific with S. prettyae as all three species have different proportions of forebody, and different body colour. For details see Lohse (1974).

Myllaena procidua Casey Figs 124-131
Diagnosis. This species may be distinguished by its body shape (Fig. 124), small size (about 1.6-2.3 mm long), antennal articles VII-X elongate (Fig. 124), and the shape of the median lobe of the aedeagus and the spermatheca (Figs 125, 126, 131). It is worthy to note that the median lobe of M. procidua is similar to that of M. kaskaskia Klimaszewski and M. vulpina Bernhauer, but the shape of the spermatheca differs significantly and has much better diagnostic features for identification of this species.
Distribution. Bionomics. The Newfoundland specimens were taken on the gravel banks of a stream and a river. In New Brunswick, adults occurred along river (clear water) margins among cobblestones set in sand and fine gravel at the water's edge, or among gravel at the edge of the water ). Adults were located by turning over cobblestones and larger pebbles ). In New Brunswick, adults were collected during May, June, July and August, by turning over cobblestones and pebbles ).