Contributions to the knowledge of the Aleocharinae ( Coleoptera , Staphylinidae ) in the Maritime Provinces of Canada

Since 1970, 203 species of Aleocharinae have been recorded in the Maritime Provinces of Canada, 174 of which have been reported in the past decade. Th is rapid growth of knowledge of this hitherto neglected subfamily of rove beetles occasions the present compilation of species recorded in the region together with the chronology of their discovery. Sixteen new provincial records are reported, twelve from Nova Scotia, one from New Brunswick, and three from Prince Edward Island. Seven species, including Oxypoda chantali Klimaszewski, Oxypoda perexilis Casey, Myllaena cuneata Notman, Placusa canadensis Klimaszewski, Geostiba (Sibiota) appalachigena Gusarov, Lypoglossa angularis obtusa (LeConte), and Trichiusa postica Casey [tentative identifi cation] are newly recorded in the Maritime Provinces, one of which, Myllaena cuneata, is newly recorded in Canada. A preliminary analysis of the composition of the fauna indicates that the percentage of adventive species (18.2%) is consistent with that of other groups of Coleoptera. Both Cape Breton Island and Prince Edward Island are comparatively faunistically under-represented, in all probability as a result of insuffi cient collecting eff ort in these areas. A species accumulation curve indicates that it is probable that further species of aleocharines remain to be documented in the region.


Introduction
Th e recent explosion of interest and information with respect to the rove beetle subfamily Aleocharinae in the Maritime Provinces of Canada (New Brunswick, Nova Scotia, and Prince Edward Island) has been remarkable and dramatic, particularly given the long history of neglect of this group in the region.Th is lack of attention is in many respects unsurprising, given the complex and diffi cult taxonomy of the group.Even so, in comparison with other groups of Coleoptera in the region, and with interest in aleocharines in other portions of the continent, the historical attention that this group has received in the region in the past has been exceptionally meagre.
Th e fi rst published report of an aleocharine from the Maritime Provinces was by Howden (1970) who recorded Falagria dissecta Erichson on Sable Island, Nova Scotia, along with fi ve other species that were tentatively identifi ed only to genus (three of these have subsequently been determined as Atheta novaescotiae Klimaszewski and Maj ka, Mocyta breviuscula (Mäklin), and Crataraea suturalis (Mannerheim) (C.G.Majka and J. Klimaszewski, unpublished data).Th ere are no records of any aleocharines from the Maritime Provinces in catalogues such as Leng (1920) and Moore and Legner (1975), nor in any of the historical papers on the Coleoptera of the region.Th ere are voucher specimens of aleocharines from the region collected as early as 1910, however, the unresolved taxonomy of the group prohibited investigators from identifying them.
It was not until studies such as Klimaszewski (1979Klimaszewski ( , 1982aKlimaszewski ( , 1982bKlimaszewski ( , 1984) ) and Hoebeke (1985) that taxonomists began examining aleocharine specimens from the Maritime Provinces and including such records in taxonomic treatments.Campbell and Davies (1991), a compilation of Coleoptera records from Canada and Alaska, listed only 27 species from the region, based almost entirely on records provided by the above studies.
Th ere was very little further research on this subfamily in the Maritime Provinces for the next decade, until in 2001 a series of papers began that, over the span of the last decade, has dramatically increased knowledge of the aleocharine fauna of the region.One hundred and seventy-four species have been added to the region's faunal list during this time.Due to this very rapid increase in knowledge, it has been diffi cult to keep track of all the contributions to the region's faunal lists, and even the recent catalogue of Gouix and Klimaszewski (2007) is now substantially out of date.
Th e purpose of this paper is to add further jurisdictional records of aleocharines to the region's faunal list, provide a compendium of the species that have been recorded in the Maritime Provinces, and the studies that have documented their presence, and briefl y examine some aspects of the fauna in general, and of the increase in knowledge of the group in the region.

Methods and conventions
Codens (following Evenhuis 2009) of collections referred to in this study are: Aleochara castaneipennis is newly recorded in Nova Scotia.In Canada it has been previously recorded in Alberta, British Columbia, New Brunswick, Ontario, Québec, and the Yukon (Klimaszewski 1984;Klimaszewski et al. 2005a).In the United States it has been recorded in many jurisdictions in the eastern and western portions of the country, although it is absent in the Great Plains region (Klimaszewski 1984).
Oxypoda chantali is newly recorded in the Maritime Provinces.Th is species is previously known only from Ontario and Québec (Klimaszewski et al. 2006b).It has been collected in leaf litter in deciduous forests (Klimaszewski et al. 2006b).Oxypoda perexilis is newly recorded in the Maritime Provinces.In Canada it has been previously recorded in Ontario and Québec.In the United States it has been recorded in Mississippi, Texas, North Carolina, and Iowa (Klimaszewski et al. 2006b).In other regions it has been collected in dry alvar habitats (Klimaszewski et al. 2006b).
Myllaena arcana is newly recorded in Nova Scotia.In Canada it has been previously recorded in Alberta, New Brunswick, Ontario, and Québec.In the United States it has been found from New Hampshire, west to Iowa and south through Florida and Alabama to Veracruz and Chiapas in Mexico (Klimaszewski 1982a).Specimens have been collected from wet debris near streams, lakes, and ponds (Klimaszewski 1982a).Myllaena cuneata is newly recorded in Canada.In the United States this species has been found from Florida and Louisiana north to Massachusetts.Specimens have been collected from organic detritus near a creek and in oak-beech leaf litter (Klimaszewski 1982a).Eumicrota socia is newly recorded in Prince Edward Island.In Canada it has been previously recorded in New Brunswick, Nova Scotia, and Québec.It is widely distributed in the central and eastern portions of the United States.(Campbell and Davies 1991;Klimaszewski et al. 2009c).Specimens have been collected in a wide variety of coniferous and deciduous forests, frequently on slightly decayed polypore fungi and gilled fungi of a variety of species (Klimaszewski et al. 2009c Gyrophaena gaudens is newly recorded in Prince Edward Island.In Canada it has been previously recorded in New Brunswick, Ontario, and Québec.In the United States it has been recorded in northern regions of the country from Massachusetts and Pennsylvania in the east, west to Michigan and Wisconsin (Klimaszewski et al. 2009c).It is found in mixed and coniferous forests on a variety of gilled and polypore fungi (Klimaszewski et al. 2009c).Silusa alternans is newly recorded in Prince Edward Island.In Canada it has been previously recorded in New Brunswick, Nova Scotia, and Québec.In the United States it has been recorded from Georgia north to New Hampshire (Klimaszewski et al. 2003).It has been collected in deciduous and coniferous forests associated with gilled fungi such as Clavaria sp. and Russula sp.(Klimaszewski et al. 2003).Placusa canadensis is newly recorded in the Maritime Provinces.In Canada it has been previously recorded in Ontario and Québec; in the United States it is known from Ohio and West Virginia (Klimaszewski et al. 2001).In Québec this species has been found predominantly in sugar maple (Acer saccharum Marsh.)stands, occasionally in white spruce (Picea glauca (Moench) Voss) forests.Th ey have been collected from under the bark of recently fallen trees and from rotting fungi and tree stumps (Klimaszewski et al. 2001).Th e specimens in Nova Scotia were found in association with specimens of Carpophilus sayi Parsons [Nitidulidae] (abundant), and Corticeus tenuis (LeConte) [Tenebrionidae] (infrequent) in the same subcortical habitat.
Acrotona subpygmaea is newly recorded in Nova Scotia.In Canada it has been previously recorded in New Brunswick; in the United States there are records from Massachusetts and Indiana (Klimaszewski et al. 2005a).In New Brunswick it was collected in a red spruce (Picea rubens Sarg.) forest (Klimaszewski et al. 2005a).
Th e status of Acrotona subpygmaea, however, is subject to some question.In most respects it appears to be identical to Acrotona avia (Casey).Th ere is an unresolved problem in determining the status of these two species names in that while all the external and internal structures of both male and female types of A. avia are intact, in the case of the (unpublished) lectotype of A. subpygmaea designated by V. Gusarov, the median lobe of the adeagus of the male is missing and the female syntype has a collapsed spermatheca, making it diffi cult to determine whether these are distinct species or whether A. avia should be designated as a junior synonym of A. subpygmaea.J. Klimaszewski and collaborators are in the process of revising the eastern Canadian species of the genus Acrotona.Th e present identifi cation should be regarded as tentative, pending this revision.Canning Field, Kejimkujik National Park, 26.VI.-6.VII.2004, 14-23.VIII.2004, H. Love, hemlock forest, pitfall trap (18, CGMC); Cobreille Lake, 27.VI-7.VII.2004, H. Love, hemlock forest, pitfall trap (43, CGMC).Atheta (Microdota) particula is newly recorded in Nova Scotia.In Canada it has been previously recorded in New Brunswick (Klimaszewski et al. 2005a).In the United States it has been recorded from Rhode Island and New York (Moore and Legner 1975).In New Brunswick it was collected in a red spruce forest (Klimaszewski et al. 2005a).In Nova Scotia they have primarily been found on the forest fl oor in eastern hemlock (Tsuga canadensis (L.) Carr.) forests.
Geostiba appalachigena is newly recorded in the Maritime Provinces.In Canada it has been previously recorded in Québec.In the United States it has been collected from Maine to Virginia, west to Wisconsin (Gusarov 2002).It has been found in red spruce and balsam fi r (Abies balsamaea (L.) Mill) forests, in forest leaf litter (Gusarov 2002).
Lypoglossa angularis obtusa is newly recorded in the Maritime Provinces.In Canada it has been previously recorded in Newfoundland and Québec; in the United States it is found in Maine and New Hampshire (Gusarov 2004).Th e species is common in forest leaf litter and moss in boreal forests; it has also been found on dung in gopher burrows (Gusarov 2004).Trichiusa postica is newly recorded in the Maritime Provinces.In Canada it has been previously recorded in Ontario (Campbell and Davies 1991;Gusarov 2001Gusarov -2003)).Th e ecology and biology of this species have not been recorded.

Trichiusa postica
Th is identifi cation should be regarded as provisional.Trichiusa is an unrevised genus in North America, and for confi rmation, this specimen should be compared with type specimens of this genus.Th ese are on loan from the US National Museum to V. Gusarov and despite eff orts we have not been able to obtain them for the purposes of this study.
Zyras obliquus is newly recorded in Nova Scotia.In Canada it has been previously recorded from British Columbia east to New Brunswick (Klimaszewski et al. 2005b;Webster et al. 2009).In British Columbia this species was found in various coniferous and mixed forests (Klimaszewski et al. 2005b).Note: this species was reported from Nova Scotia by Kehler et al. (1996) [as Zyras haworthi (Stephens)] without, however, supplying collection data.In a subsequent examination of this collection by Majka and Bondrup-Nielsen (2006), no voucher specimens of this species were found, rendering the authenticity of the original record moot.

Discussion
Table 1 provides a systematic list of the 203 species of aleocharines that have been found in the Maritime Provinces.Of these, fi ve species [Phloeopora sp., Oligota chrysopyga Kraatz?, Oligota nr.rufi cornis Sharp, Acrotona nr.smithi Casey, and Atheta nr.smetanai & campbelli (Lohse)] are provisional names for species that have not yet been identifi ed to the specifi c level.Th ree species (Philhygra insulivaga Gusarov, Philhygra lustrivaga Gusarov, and Philhygra riprivaga Gusarov) are unpublished manuscript names of species which have not yet been formally described.Published references for reports from the Maritime Provinces are arranged in chronological order.
Of the 203 species, 162 (79.8%) are Nearctic in distribution; four (2.0%) have a Holarctic distribution; and 37 (18.2%) are adventive Palaearctic species.A total of 175 species (86.2%) have been recorded in New Brunswick; 125 (61.6%) in Nova Scotia, and 20 (9.9%) in Prince Edward Island.Of the Nova Scotia species, 106 (52.2%) have been recorded on the Nova Scotia mainland, and 57 (28.1%) on Cape Breton Island.Th ere are 19 species recorded on Cape Breton Island that have not been found on the Nova Scotia mainland.
Since the biodiversity of the Maritime Provinces aleocharine fauna is still in an active phase of investigation, it would be premature at present to draw many conclusions from these compositional fi gures.Th e overall proportion of adventive species is similar to that of other groups of Coleoptera.For example, in Nova Scotia 15.6% of the province's beetle fauna consists of adventive species (C.G.Majka, unpublished data).Th e proportion of species recorded to date from both Cape Breton Island (28.1%) and Prince Edward Island (9.9%) appear to be rather low, in all probability indicating a defi cit in collection eff ort for this group in these areas.In the case of the Carabidae, 54.4% of the Maritime Provinces' fauna has been recorded on Cape Breton, and 47.9% on Prince Edward Island (Majka et al. 2007b).Within the Curculionoidea, 35.3% of Maritime Provinces weevils have been recorded on Cape Breton, and 33.2% on Prince Edward Island (Majka et al. 2007a reason why these fi gures should be the same across diff erent taxonomic groups, the data for these better investigated groups in the region appear to underscore the fact that a comparative paucity of collecting eff ort has under-represented the aleocharine fauna of these two areas. An indication of the rapid growth of information about the Maritime Provinces' aleocharine composition is provided by Figure 1, a species accumulative curve (based on publication dates) of the region's fauna.Fig. 1 shows that that an asymptote has not yet been approached, suggesting that the fauna of the area is not adequately sampled, and that many additions to it remain to be made.Although the very rapid growth rate of knowledge over the past decade is likely to abate in the future, it is nevertheless clear that more species remain to be documented.Even since the recent publication of Gouix and Klimaszewski (2007), a catalogue of the Aleocharinae of Canada and Alaska, which included records of 96 species from the Maritime Provinces, 107 species have been added to the region's fauna -a 111% increase in the past three years alone.

Figure 1 .
Figure 1.Species accumulation curve of the Maritime Provinces Aleocharinae

Table 1 .
).While there is no a priori Aleocharinae recorded in the Maritime Provinces of Canada.