Canadian Journal of Identification No. 42 (December, 2020) SHERIN

Soldier of the subfamily of Canada (Diptera, ) Linley M. Sherin McGill University, Department of Natural Resource Sciences, Macdonald Campus, 21,111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec, H9X 3V9, Canada.

Corresponding author: [email protected] Abstract The Pachygastrinae are a large, globally distributed subfamily of soldier flies (Diptera, Stratiomyidae). Despite being widespread, they have poor representation in museum collections and are mostly known from larvae collected under the bark of fallen logs. All seven Canadian genera and nine of the eleven Canadian are herein reviewed and keyed. An updated checklist to the Canadian species is presented. Twenty-one new provincial records are reported, and four species are recorded from Canada for the first time: Cosmariomyia pallidipennis (Williston), Gowdeyana punctifera (Malloch), vitrea Hull and pulchra Loew. This increases the known fauna in Canada from seven to 11 species.

Published online December 04, 2020

Introduction Adults of the Nearctic Region are small (2.0–­3.6 mm), The Stratiomyidae, or soldier flies, are a large, predominantly black flies, often with silvery vestiture cosmopolitan family (~2850 spp.) of lower brachyceran (Kraft and Cook 1961; Woodley 2001). Though sexual flies that are diverse in both size and morphology (Hauser dimorphism is prevalent in soldier flies, Pachygastrinae et al. 2017; James 1981). There are 114 species recorded often display only subtle variation between sexes (Curran from Canada. However, a recent review of Canadian 1927). Adults of many species form swarms, and the Diptera predicted an additional 5-10 species remain to be Nearctic species Gowdeyana punctifera Malloch has recorded or described (Savage et al. 2019). The Canadian been recorded in swarms of up to 50 individuals (Woodley stratiomyid fauna includes species in seven of the twelve 2001). For unknown reasons, many species are collected subfamilies: Antissinae, Stratiomyinae, Beridinae, from windows (Hull 1930) and few were collected prior Sarginae, Nemotelinae, Clitellariinae and Pachygastrinae to the common use of Malaise traps (Woodley 2001). (McFadden 1972, Woodley 2001). I here review the Adults appear attracted to dead wood or fallen trees of the 11 Canadian species of Pachygastrinae. where females oviposit (Woodley 2001). Pachygastrinae are a predominantly tropical subfamily Relatively little is known about the habitat with a global distribution. Possibly due in part to their associations and feeding habits of larval Pachygastrinae small size, they have poor representation in collections (Woodley 2001). Larvae are universally brown to white, when compared with larger stratiomyids. Pachygastrinae flattened dorso-ventrally and vary in length from 4.0­–7.2 are morphologically distinguished from other Canadian mm (Kraft and Cook 1961). Pachygastrine larvae are Stratiomyidae in having five visible abdominal tergites terrestrial and have been found under the bark and in tree (tergites 6 and 7 reduced), wing with m-cu crossvein holes of both deciduous and coniferous trees (Kraft and connected to vein M3+4, and in having only three veins Cook 1961; McFadden 1967). They appear to feed on arising from the discal medial cell (Fig. 1; James 1981; either the sap or microorganisms that occur on the moist Hauser et al. 2017). This subfamily was previously wood of wounded and dying trees (McFadden 1967) thought to be paraphyletic (Nagatomi and Iwata 1978; and use cylindrical brush-like mouthparts to sweep food Woodley 2001), however the only molecular study into their oral cavity (Cook 1953; Kraft and Cook 1961; of Stratiomyid phylogeny (Brammer and von Dohlen McFadden 1967). It has been suggested previously that 2007) found evidence of a monophyletic Pachygastrinae. the larvae are predatory (Malloch 1917; Johannsen 1922; Monophyly was also supported in a 2010 morphological James 1981). However, McFadden (1967) and Woodley analysis (Brammer and von Dohlen 2010), though (2001) considered it doubtful given their common pachygastrine representation was limited. appearance in large numbers with McFadden (1967)

The Canadian Journal of Arthropod Identification is a product of the Biological Survey of Canada and the Entomological Society of Canada.

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Figure 1. Wing of Pachygaster pulchra Loew, edited to highlight characteristic wing venation of the subfamily Pachygastrinae in red; m-cu crossvein connected to M3+4, and only three veins arising from cell dm (M1, M2 apical and M4). Terminology follows Cumming and Wood (2017). Abbreviations: dm – discal medial cell; M – medial vein or media; M1+2 – fused first and second branch of medial vein;M1 – first branch of medial vein; M2 – second branch of medial vein; M3+4 – fused third and fourth branch of medial vein; M3 – third branch of medial vein; M4 – fourth branch of medial vein; m-cu – medial-cubital crossvein, m-m – medial crossvein. recording over 100 larvae existing under the bark of a Despite past attempts to generate a larval key to single log. The Canadian species Berkshiria albistylum species of Nearctic Pachygastrinae, no complete key Johnson has also been reared from a large number of currently exists. Kraft and Cook (1961) provided a larvae located under the bark of a fallen poplar tree larval key to genera and larval keys to species for three (Marshall, S.A., pers. comm.). genera (Eidalimus Kertesz, Gowdeyana Curran (as Previous work addressing the Canadian pachygastrine Kertesz) and Coquillett). Most fauna has been limited and largely attributable to a small recently, McFadden (1967) provided a larval key to the number of dedicated dipterists. Kraft and Cook (1961) genera of Stratiomyidae in America north of Mexico and provided a revision of the Pachygastrinae of America incomplete larval keys to species. north of Mexico, including keys to 21 species, 13 of Current pachygastrine adult keys are also inadequately which were newly described in that paper. Following illustrated and none present an up-to-date review of the Kraft and Cook, James (1965) provided a supplementary Canadian fauna; the last Nearctic revision (Kraft and revision and key to the genera of the southwestern Cook 1961) included only five of the 11 Canadian species. United States and parts of Mexico, adding two species to I here key the seven Canadian genera including nine of the Nearctic fauna (one new species, Zabrachia yuccae the 11 Canadian species, illustrating adult diagnostic James, and one new Nearctic record, Cosmariomyia characters with photographs, adding new characters and pallidipennis (Williston)). James (1981) provided highlighting taxa that need formal revision. Four of the illustrated adult and larval keys to the subfamilies and species included here are new Canadian records (Table genera of Nearctic Stratiomyidae within the Manual of 1). By providing an updated and interactive key to the Nearctic Diptera, referencing 24 pachygastrine species Canadian fauna, I hope to encourage the future study of in its generic treatment. Most recently, Woodley (2001, the Pachygastrinae in Canada and bring attention to the 2011) provided a catalogue of the global Stratiomyidae. need for a global revision of the subfamily. I also hope This catalogue included 25 Nearctic pachygastrine that this key serves as a tool for amateur naturalists to species in nine genera, adding the species Artemita nana discover these beautiful and elusive flies. (Bellardi) to the Nearctic fauna. Of these 25 species, Woodley reported seven species from Canada (Berkshiria Materials and Methods albistylum Johnson, Eidalimus fuscus (Kraft & Cook), Species included in this key are those previously Neopachygaster maculicornis (Hine), N. occidentalis known from Canada (Woodley 2001) as well as new Kraft & Cook, N. reniformis Hull, Zabrachia plicata Canadian records reported from specimen data for the (Kraft & Cook) and Z. polita (Coquillett)) and another first time (Table 1). five species were recorded from the adjacent USA. Specimen data were obtained from the University

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of Guelph Collection (DEBU, Guelph, Ontario), photograph. the Biodiversity Institute of Ontario (BOLD, Guelph, Ontario), the Canadian National Collection of , Results Arachnids and Nematodes (CNC, Ottawa, Ontario), In total, 439 specimens were examined (52 DEBU, the Lyman Entomological Museum (LEMQ, Montréal, 20 BOLD, 262 CNC, 1 LEMQ, 101 QMOR, 2 UBCZ, Quebéc), the Ouellet-Robert Entomological Collection 1 iNaturalist) that correspond to nine species and seven (QMOR, Montréal, Quebéc), the Spencer Entomological genera (Table 1). Within this material, three specimens Collection (UBCZ, Vancouver, British Columbia) and were damaged and not identifiable to species. See the online platform iNaturalist [accessed 2020 October Appendix 1 for a complete list of examined specimens. 17]. Notably, no pachygastrine species have been recorded The following collections were also examined but held from provinces east of Quebec. This is potentially due to no Canadian Pachygastrinae: the Royal Ontario Museum sampling bias, as the most widespread species appear to (ROM, Toronto, Ontario), the Royal British Columbia exist wherever there are forested areas. Museum (RBCM, Victoria, British Columbia), the The genus Zabrachia needs revision, which is Cornell University Insect Collection (CUIC, Ithaca, New beyond the scope of this review. Therefore, the key York, USA), as well as the online platform BugGuide identifies Zabrachia specimens only to generic level. (https://bugguide.net/) [accessed 2020 October 17]. Neopachygaster Austen is also in need of revision. All Terminology used follows Cumming and Wood Neopachygaster species are included within the key (2017). Data included within species pages were although only a single character separates the three taken from specimen label data unless otherwise cited. most widespread species (Neopachygaster reniformis Labels without GPS coordinates for locality data had Hull, N. vitrea Hull and N. maculicornis (Hine)). As coordinates generated retroactively using Google Maps Pachygastrinae are a predominantly tropical subfamily, GPS Coordinates (https://www.gps-coordinates.net). it is recommended that revisions of any Canadian Distribution maps were created using the online software genera take place within larger revisions, ideally of SimpleMappr (Shorthouse 2010). Previous Canadian the global fauna. It has been previously recommended distribution data were taken from literature (Woodley that the entire subfamily is revised (Woodley 2001; 2001) and mapped using whole provinces to indicate the Hauser, M., pers. comm) and the findings presented here presence of a species. This does not imply distribution support this recommendation for a global revision of the throughout the entire highlighted regions. Canadian Pachygastrinae. collection localities for the examined specimens were In total, I present 21 new provincial distribution included in the distribution map as point data. For records and four new national distribution records. This brevity, the term “provincial” is used when describing includes records from four provinces from which the both provincial and territorial records throughout this subfamily had not previously been known. The following manuscript and the provided key. species are recorded from Canada for the first time; Specimen photographs were taken using a Canon Cosmariomyia pallidipennis (Williston), Gowdeyana DSLR mounted on a Stackshot rail and operated using punctifera (Malloch), Neopachygaster vitrea Hull and Helicon Remote. Photographs were then stacked using Pachygaster pulchra Loew. This increases the known Helicon Focus and edited using Adobe Photoshop. All pachygastrine fauna in Canada from seven to 11 species, specimen photographs were taken and edited by the and the known stratiomyid fauna from 114 to 118 species author unless otherwise indicated. Photographs of living (Savage et al. 2019). flies are from multiple sources; credit is given below each

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Table 1. Checklist of Canadian Pachygastrinae arranged from west to east, by province and then territory: BC, British Columbia; AB, Alberta; SK, Saskatchewan; MB, Manitoba; ON, Ontario; QC, Quebec; NB, New Brunswick; NS, Nova Scotia; PE, Prince Edward Island; NL, Newfoundland and Labrador; YT, Yukon; NT, the Northwest Territories; NU, Nunavut. *New provincial record. **New national record.

Taxon BC AB SK MB ON QC NB NS PE NL YT NT NU Canada Berkshiria albistylum Johnson 7* 15 1* 23 Cosmariomyia pallidipennis (Williston) 1* 1** Eidalimus fuscus (Kraft & Cook) 8 2* 10 Gowdeyana punctifera (Malloch) 1* 1* 6* 1* 9** Neopachygaster maculicornis (Hine) 6* 6 15* 13* 40 Neopachygaster occidentalis Kraft & Cook 1 1 Neopachygaster reniformis Hull 5* 7* 5* 9* 25 38 89 Neopachygaster vitrea Hull 35* 18* 53** Pachygaster pulchra Loew 8* 8** Zabrachia spp. Coquillett 83 22* 16 75 5* 1* 202 TOTAL SPECIMENS 90 35* 12 16* 129 148 0 0 0 0 5* 1* 0 436

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flattened setae hair-like setae

hair-like flattened setae setae

1. Scutum with metallic flattened setae. 1’. Scutum with only hair-like setae, varying Setae sometimes grouped together into in colour from shiny white to brown. tufts and often aligned in rows. Setae occurring singly and not aligned in rows. …Couplet 2 …Couplet 4

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flattened hair-like and grouped

flattened and flattened grouped and singular

scutal setae scutal setae grouped singular 2. Flattened scutal setae grouped into 2’. Flattened scutal setae separated from one tufts. another.

Setae on abdominal tergites 3-5 flattened Abdominal setae on tergites 3-5 hair-like and grouped into tufts, matching metallic and varied in colour from white to brown, scutal setae. not matching metallic, flattened scutal setae. Widespread. …Gowdeyana punctifera (Malloch) Eastern. …Couplet 3

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stylus stylus arista-like plumose

upper frons sparse setae

lower frons tomentum tomentum face

3. Stylus arista-like, bare or with very 3’. Stylus plumose with dense black short pubescence giving it a thin, wire-like pubescence giving it a thickened appearance. appearance.

Upper frons mostly glossy, with sparse Upper frons tomentose, similar in setae unlike the tomentum (dense, silver appearance to lower frons and face. pubescence) of the lower frons and face. …Eidalimus fuscus (Kraft & Cook) …Cosmariomyia pallidipennis (Williston)

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basal complex of basal complex flagellum of flagellum cylindrical posterior rim reniform no rim scutellum

basal complex of flagellum

cylindrical reniform flagellum flagellum

4. Scutellum with distinct thin posterior rim. 4’. Scutellum evenly rounded without distinct, thin posterior rim. Basal complex of flagellum elongated anterior-posteriorly and cylindrical. Basal complex of flagellum shortened anterior-posteriorly and disc-like or reniform (kidney-like) in shape. …Berkshiria albistylum Johnson …Couplet 5

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r4 r3 r3

R4+5 R5 R4

5. R4 wing vein fused with R5 wing vein to 5’. R4 and R5 wing veins both present, create R4+5 wing vein and a single cell creating two distinct cells along along costal edge (r3). costal edge (r3 and r4).

…Zabrachia Coquillett …Couplet 6

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tomentum bare and glossy lower lower frons frons

dark inner no dark inner process process

6. Antennae with smooth, dark inner 6’. Antennae without smooth, dark inner process. process.

Lower frons depressed with dense, Lower frons evenly rounded, bare and silver tomentum. glossy, without tomentum.

Widespread. Eastern. …Neopachygaster Austen (4 spp.) …Couplet 7 …Pachygaster pulchra Loew

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pleural suture band of pleural suture silver setae bare

7. Thorax with a vertical band of dense silver 7’. Thorax bare anterior to the pleural setae anterior to the pleural suture. suture, without a vertical band of dense silver setae. Widespread. Western. …Couplet 8 …Neopachygaster occidentalis Kraft & Cook

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no bare bare area bare areas area(s) ______midline midline midline

8. Pubescence on the 8’. Pubescence on the 8’’. Pubescence on the anterior margin of the anterior margin of anterior margin of mesonotum interrupted the mesonotum the mesonotum entire, by a single bare area on interrupted by two not interrupted. either side of disconnected bare areas longitudinal midline. on either side of Widespread. longitudinal midline. Widespread. …Neopachygaster Eastern. …Neopachygaster reniformis Hull …Neopachygaster vitrea Hull maculicornis (Hine)

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Gowdeyana punctifera (Malloch) Gowdeyana punctifera is distinguished from other Canadian pachygastrines by flattened setae on the thorax and abdominal terga. The thoracic setae are often grouped into tufts, rather than occurring singly. Gowdeyana (Malloch) is a mostly Neotropical genus with G. punctifera being one of only two Nearctic species.

Adults have been collected by Malaise trap and by sweeping grasses and adult males have been recorded in swarms of up to 50 individuals (Woodley 2001). Larvae have been collected from under the bark of hickory (Carya), poplar (Populus) and pine (Pinus) species (Kraft and Cook 1961; McFadden 1967). It is unusual amongst Pachygastrinae in developing in both coniferous and deciduous trees. The other known Canadian pachygastrine species with this dual association is Neopachygaster occidentalis.

Photo courtesy of Walter B. Klockers Lateral Dorsal

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Gowdeyana punctifera (Malloch) Gowdeyana punctifera

Known distribution of Gowdeyana punctifera (Malloch) in Canada from locality data of examined specimens. This species is newly recorded in Canada with distribution in British Columbia, Saskatchewan, Ontario and Quebec.

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Eidalimus fuscus (Kraft & Cook) Eidalimus fuscus is distinguished by an arista-like stylus, flattened silver setae on the scutum and cylindrical setae on the abdominal tergites. Compared to the two other Canadian species with flattened scutal setae (Cosmariomyia pallidipennis and Gowdeyana punctifera), E. fuscus has fewer flattened scutal setae.

Adults have been collected from oak savannah habitat using Malaise traps. Larvae have been collected from under the bark of willow (Salix) and have been found in groups from 5-20 under the bark of a single log (McFadden 1967).

Lateral Dorsal Photo courtesy of Katja Schulz (CC by 2.0)

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Eidalimus fuscus (Kraft & Cook) Eidalimus fuscus Literature

Known distribution of Eidalimus fuscus (Kraft & Cook) in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This species was previously known from Ontario and is newly recorded in Quebec.

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Cosmariomyia pallidipennis (Williston) Cosmariomyia pallidipennis is the only species with Nearctic distribution in the mostly Neotropical genus Cosmariomyia Kertesz. The thorax is covered in silvery vestiture, as in Eidalimus fuscus and Gowdeyana punctifera. However, C. pallidipennis is easily distinguished from these species and all other Canadian pachygastrines by its plumose antennal stylus, Fig. 1 densely covered in dark setae.

This species has been observed ovipositing in hardwood (Fig. 1) but nothing further is known about its biology.

Photo courtesy of Jeff Gruber

Lateral Dorsal Photo courtesy of Jeff Gruber

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Cosmariomyia pallidipennis (Williston) Cosmariomyia pallidipennis

Known distribution of Cosmariomyia pallidipennis (Williston) in Canada from locality data of examined specimens. This species is newly recorded in Canada with a single record from Halton Region, Ontario.

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Berkshiria albistylum Johnson The relatively robust Berkshiria albistylum is easily recognizable by an arista-like stylus and the elongate basal complex of the flagellum, which is cylindrical in shape. Occasionally, B. albistylum specimens have been found with an absent or partially absent R4 wing vein, a character usually exclusive to the genus Zabrachia, but this is not diagnostic.

Adults have been collected from species of poplar (Populus) and hawthorn (Crataegus), mixed forests, hardwood forests and lakeshore habitats. They been collected by hand, Malaise trap and by rearing collected larvae. Larvae have been collected from deciduous trees, including eastern cottonwood (Populus deltoides) and Siberian elm (Ulmus pumila; McFadden 1967). Larvae have been reared from a large grouping under the bark of a fallen poplar tree (Marshall, S.A., pers. comm.).

Lateral Dorsal Photo courtesy of Steve Marshall

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Berkshiria albistylum Johnson Berkshiria albistylum Literature

Known distribution of Berkshiria albistylum Johnson in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This species was previously known from Ontario and is newly recorded in Manitoba and Quebec.

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Zabrachia Coquillett species This genus needs to be formally revised, therefore the provided key does not identify Zabrachia below the generic level. Specimens identified as the widespread species Zabrachia polita Coquillett probably include multiple undescribed species.

Zabrachia is easily distinguished from other pachygastrine genera by the fused R4 and R5 wing veins, but Z. plicata Kraft and Cook seems to be the only readily identified Canadian species of Zabrachia and is reliably diagnosed by a deep fold behind the fore coxae, best seen in lateral view.

Adult Zabrachia have been collected by hand, pan trap, Malaise trap or by rearing collected larvae to adult stage. Larvae of Zabrachia are only known from under the bark of coniferous trees including lodgepole pine (), ponderosa pine (P. ponderosa), white spruce (Picea engelmani) and douglas-fir (Pseudotsuga menziesii; Kraft and Cook 1961, McFadden 1967). Adults have been collected from pine, spruce and hemlock (Tsuga) and adult females have been collected during oviposition in pine wood. This is the only pachygastrine genus recorded from Yukon or the Northwest Territories.

Zabrachia sp.

Lateral Dorsal

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Zabrachia Coquillett species Zabrachia Literature

Known distribution of species of Zabrachia Coquillett in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This genus was previously known from British Columbia, Ontario and Quebec and is newly recorded in Alberta, Yukon and the Northwest Territories.

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Pachygaster pulchra Loew This species is easily distinguished from the other Canadian pachygastrines by the sparse setae on the thorax and reniform antennae that do not possess the black shiny inner process characteristic of Neopachygaster. Pachygaster pulchra also has a narrower abdomen than other pachygastrines, giving it a trimmer appearance (Kraft and Cook 1961).

Larvae of this species have been collected from tree crotch debris, tree holes and hollow trees (Kraft and Cook 1961).

Lateral Dorsal Photo courtesy of Matt Bertone

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Pachygaster pulchra Loew Pachygaster pulchra

Known distribution of Pachygaster pulchra Loew in Canada from locality data of examined specimens. This species is newly recorded in Canada with distribution in Ontario.

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Neopachygaster occidentalis Kraft & Cook Neopachygaster occidentalis is the only Canadian Neopachygaster found exclusively in the west. This species is easily distinguished from other Canadian Neopachygaster by the absence of a vertical stripe of silver setae anterior to the pleural suture. Neopachygaster occidentalis and other Neopachygaster differ from the similar Canadian species Pachygaster pulchra in having a dark, shiny process on the inner surface of the antennae.

Larvae of N. occidentalis have been collected from under the bark of ponderosa pine (; Kraft and Cook 1961) and under the bark of trembling aspen (Populus tremuloides) infected with Trypophloeus populi (Subfamily Scolytinae). Neopachygaster occidentalis is the only Canadian Neopachygaster known to develop on coniferous trees.

Lateral Dorsal

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Neopachygaster occidentalis Kraft & Cook Neopachygaster occidentalis Literature

Known distribution of Neopachygaster occidentalis Kraft & Cook in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This species is currently known from a single Canadian locality in Clinton, British Columbia.

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Neopachygaster reniformis Hull Neopachygaster reniformis is distinguished from other Canadian Neopachygaster species by a vertical stripe of silver setae anterior to the pleural suture and by two bare areas that interrupt the dorsal pubescence on the anterior part of the mesonotum.

Adults of N. reniformis are often found in woodpiles and have been collected from club-rush (Scirpus), maple logs (Acer) and walnut (Juglans). Adults have been collected by sweeping, Malaise traps and rearing larvae and pupae to adult stage. Puparia and larvae of this species have been collected from beneath the bark of poplar (Populus) species (Kraft and Cook 1961), including trembling aspen (Populus tremuloides).

Lateral Dorsal Photo courtesy of Matt Bertone

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Neopachygaster reniformis Hull Neopachygaster reniformis Literature

Known distribution of Neopachygaster reniformis Hull in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This species was previously known from Ontario and Quebec and is newly recorded in British Columbia, Alberta, Saskatchewan and Manitoba.

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Neopachygaster vitrea Hull Neopachygaster vitrea, the only Neopachygaster species found exclusively in eastern North America, can be distinguished from other Canadian Neopachygaster species by a vertical stripe of silver setae anterior to the pleural suture and by the four bare areas that interrupt the pubescence on the anterior mesonotum. Neopachygaster vitrea has sparser or less even pile on the mesonotum and is often smaller overall compared to either N. maculicornis or N. reniformis (Kraft and Cook 1961).

Adults have been reared from larvae collected under the bark of elm (Ulmus; Kraft and Cook 1961).

Lateral Dorsal

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Neopachygaster vitrea Hull Neopachygaster vitrea

Known distribution of Neopachygaster vitrea Hull in Canada from locality data of examined specimens. This species is newly recorded in Canada with distribution in Ontario and Quebec.

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Neopachygaster maculicornis (Hine) Neopachygaster maculicornis is distinguished from other Canadian Neopachygaster species by a vertical stripe of silver setae anterior to the pleural suture and by the uninterrupted pubescence on the anterior mesonotum. Compared to N. reniformis or N. vitrea, N. maculicornis has relatively denser metallic pile on the mesonotum.

Larvae have been collected from under the bark of eastern cottonwood (Populus deltoides) and Manitoba maple (Acer negundo; Kraft and Cook 1961). Adults have been collected by Malaise traps, from windows (Sorenson & Fluke 1953) and by rearing collected larvae.

Lateral Dorsal Photo courtesy of Steve Marshall

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Neopachygaster maculicornis (Hine) Neopachygaster maculicornis Literature

Known distribution of Neopachygaster maculicornis (Hine) in Canada based on provincial records from the literature (Woodley 2001) and locality data of examined specimens. This species was previously known from Saskatchewan and is newly recorded in Alberta, Ontario and Quebec.

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James, M.T. 1965. Contributions to our knowledge Acknowledgements of the Nearctic Pachygasterinae (Diptera: I would like to thank Steve Marshall for advising me, Stratiomyidae). Annals of the Entomological Society this review could not have been completed without his of America 58: 902–908. support and guidance, and without access to the Guelph Insect Collection (DEBU) where the lab work for this James, M.T. 1981. Stratiomyidae. Chapter 36. In study was conducted. I am grateful to all the collections Manual of Nearctic Diptera. Volume 1. Monograph which loaned me material for study and/or allowed me No. 27. Edited by McAlpine, J.F., Peterson, B.V., to identify material at their institutions (listed in full Shewell, G.E., Teskey, H.J., Vockeroth, J.R., and under Methods). I thank Steve Paiero, Morgan Jackson Wood, D.M. Research Branch, Agriculture Canada, and Jessica Gillung for editing the text and key multiple Ottawa. Pp 497–511. times and for their continued mentorship in all things Johannsen, O.A. 1922. Stratiomyiid larvae and puparia dipterology. I also thank Martin Hauser for his edits and of the north eastern states. Journal of the New York for sharing his expertise of Stratiomyidae, which helped Entomological Society 30(4): 141–153. improve the manuscript immensely. Finally, I would like Kraft, K.J., and Cook, E.F. 1961. A revision of the to thank Brad Sinclair and Joel Gibson for their helpful Pachygasterinae (Diptera, Stratiomyidae) of America and thorough reviews. north of Mexico. Miscellaneous Publications of the Entomological Society of America 3: 1–24. References Malloch, J.R. 1917. A preliminary classification of Brammer, C.A. and von Dohlen, C.D. 2007. Diptera, exclusive of Pupipara, based upon larval Evolutionary history of Stratiomyidae (Insecta: and pupal characters, with keys to imagines in Diptera): The molecular phylogeny of a diverse certain families. Part I. Bulletin of the Illinois State family of flies. Molecular Phylogenetics and Laboratory of Natural History 12: 161–407. Evolution 43: 660–673. McFadden, M.W. 1967. Soldier larvae in America Brammer, C.A. and von Dohlen, C.D. 2010. north of Mexico. Proceedings of the United States Morphological phylogeny of the variable fly family National Museum 121(3569): 1–72. Stratiomyidae (Insecta, Diptera). Zoologica Scripta 39(4): 363–377. McFadden, M.W. 1972. The soldier flies of Canada and Alaska (Diptera: Stratiomyidae). 1: Beridinae, Cook, E.F. 1953. On the early stages of Neopachygaster Sarginae and Clitellariinae. The Canadian maculicornis (Hine) and Berkshiria aldrichi Entomologist 104: 531–562. (Malloch) (Diptera: Stratiomyidae). Annals of the Entomological Society of America 46: 293–9. Nagatomi, A. and Iwata, K. 1978. Female terminalia of lower Brachycera - II. Beiträge zur Entomologie Curran, C.H. 1927. Synopsis of the Canadian 28(2): 263–293. Stratiomyidae. Proceedings and Transactions of the Royal Society of Canada 3: 191–228. Savage, J., Borkent, A., Brodo, F., Cumming, J.M., Curler, G., Currie, D., deWaard, J.R., Gibson, J.F., Cumming, J.M. and Wood, D.M. 2017. Adult Hauser, M., Laplante, L., Lonsdale, O., Marshall, morphology and terminology. Chapter 3. In Manual S.A., O’Hara, J.E., Sinclair, B.J. and Skevington, of Afrotropical Diptera. Volume 1. Introductory J.H. 2019. Diptera of Canada. ZooKeys 819: chapters and keys to Diptera families. Suricata 397–450. 4. Edited by Kirk-Spriggs, A.H. and Sinclair, B.J. South African National Biodiversity Institute, Shorthouse, D.P. 2010. SimpleMappr, an online tool to Pretoria. Pp 89–133. produce publication-quality point maps. Available from http://www.simplemappr.net [accessed 17 Hauser, M., Woodley, N.E., and Fachin, D.A. October 2020]. 2017. Stratiomyidae. Chapter 41. In Manual of Afrotropical Diptera. Volume 2. Nematocerous Sorenson, J.S. and Fluke, C.L. 1953. The male genitalia Diptera and lower Brachycera. Suricata 5. Edited by of the Stratiomyidae with special reference to Kirks-Spriggs, A.H., and Sinclair, B.J. South African Wisconsin species. Annals of the Entomological National Biodiversity Institute, Pretoria, South Society of America 46(3): 337–342. Africa. Pp 919–979. Woodley, N.E. 2001. A world catalog of the Hull, F.M. 1930. Notes on several species of North Stratiomyidae (Insecta: Diptera). Myia: The American Pachygasterinae (Diptera : Stratiomyidae) International Journal of the North American with the description of a new species. Entomological Dipterists’ Society 11: 1–473. News 41: 103–106.

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