Nephrocerus slossonae Johnson

Skevington, Jeffrey H., 2005, Revision of Nearctic Nephrocerus Zetterstedt (Diptera: Pipunculidae), Zootaxa 977, pp. 1-36 : 27-30

Nephrocerus slossonae Johnson ( Figs 1 B, D, E, 2C, 4E, 11A–D, 12)

Nephrocerus slossonae Johnson, 1915: 55 .

Type Material Examined: Holotype ♂: [ United States], N[ew] H[ampshire], Bretton Woods, [44°15' N, 71°26' W], 28.vi. [19]13, JSS#13449, C.W. Johnson Collector, Holotype No. [13093] ( MCZ). Paratypes: UNITED STATES: New Hampshire: same location as holotype, 25. vi.1913, 1 Ψ, JSS#13451, 1 ♂, JSS#13452 [1 wing glued to label, other wing missing] C.W. Johnson ( MCZ); [Coos Co.], M[oun]t Washington, [44°16' N, 71°18' W], 1♂, JSS#11463, Coquillet Collection, Paratype 19095 ( USNM); M[oun]t Washington, 4. vii.1914, 1 ♂, JSS#13453, C.A. Frost, C.W. Johnson collection, Paratype 13093 ( MCZ); M[oun]t Washington, 4. vii.1914, 1 ♂, JSS#13454, C.A. Frost, Paratype [13093] ( MCZ).

Other Material Examined: CANADA: Alberta: Edmonton, [53°33' N, 113°28' W], 18. vi.1947, 1 Ψ, JSS#11497, E.H. Strickland ( CNC); Kananaskis, For[est] Exp[erimental] Sta[tion] Seebe, [51°06' N, 115°04' W], 3. vii.1968, 1 ♂, JSS#11490, H.J. Teskey ( CNC); Ontario: Hilton Beach, [46°15' N, 83°53' W], Malaise trap, at edge of h[ar]dw[oo]d for[est] and field, 31. v.1990, 1 ♂, JSS#11412 [epandrium very wide for this species, other characters are consistent with N. slossonae ; all legs removed for DNA extraction], 1♂, JSS#11413, 1Ψ, JSS#11415, 6. vi.1990, 1 ♂, JSS#11416 [genitalia badly damaged, disarticulated; head removed for DNA extraction], J.E. Swann ( DEBU); Fathom Five Nat[ional] Park, Land Base, [45°17' N, 81°40' W], sweep in dry cedar, 23. vi.1995, 1 Ψ, JSS#11436, S.A. Marshall, debu 0 0 0 75079 ( DEBU); [Hastings Co.], Maynooth, [45°14' N, 77°57' W], 2–3. vi.1982, 1 ♂, JSS#11679 [entire specimen in glycerin], B.M. Nelson ( CNC); Lambton County, Pinery Provincial Park, [43°15' N, 81°51' W], Malaise trap, oak savanna, 12– 15. vi.1992, 1 ♂, JSS#943 [1 leg used for DNA extraction], J. Skevington ( DEBU); Lambton County, Pinery Provincial Park, Burley Campground, [43°14' N, 81°53' W], Malaise trap, wet meadow, 7–14. vi.1995, 1 ♂, JSS#942 [1 leg removed for DNA extraction], 15– 19. vi.1995, 1 ♂, JSS#11409, 1 ♂, JSS#11410 [tergites 1 and 2 removed for DNA extraction], J. Skevington ( DEBU); Lambton County, Port Franks, Watson Property near L­lake, [43°13' N, 81°54' W], Malaise trap, 1–6. vi.1996, 1 ♂, JSS#11405, 8–10. vi.1996, 2 ΨΨ, JSS#945, debu00224107, J. Skevington ( DEBU); Hamilton, [43°14' N, 79°57' W], 19. vi.1979, 1 ♂, JSS#11428, S. Beierl ( DEBU); Quebec: Gatineau Co., Masham Twp., [45°41' N, 76°03' W], 22. v.1977, 1 Ψ, JSS#9907, 27–31. v.1974, 1 ♂, JSS#9908 [genitalia missing], D.M. Wood ( CNC); [Gatineau Co., Masham Twp.], Duncan Lake n[ea]r Rupert, [45°41' N, 76°03' W], 30. v.1971, 1 Ψ, D2994, JSS#11493, 5. vi.1971, 1 ♂, 16, JSS#11492, J.F. McAlpine ( CNC); Old Chelsea, Summit King Mountain, [45°29' N, 75°52' W], 1150 feet, [351 m], 25. v.1964, 1 ♂, JSS#9910, Idema illustration [identified in Manual of Nearctic Diptera as Nephrocerus daeckei ], J.R. Vockeroth ( CNC); UNITED STATES: Maine: York Co., West Lebanon, [43°23' N, 70°57' W], Malaise trap, 29.v.–11. vi.1990, 1 ♂, JSS#11836, D.W. Barry ( DENH); Minnesota: Cook Co., Min. F.S., Hovland, [47°50' N, 89°58' W], Malaise trap, 30. v.1973, 1 ♂, JSS#13378 ( UMSP); New Hampshire: Coos Co., Norton Pool, 3 mi [les] NE East Inlet Dam, [45°12' N, 71°07' W], Malaise trap, 12– 24. vi.1986, 1 ♂, JSS#11833, D.S. Chandler ( DENH); [Coos Co.], M[oun]t Wash[ingto]n, [44°16' N, 71°18' W], 1♂, JSS#13392 [only abdomen remaining on point], Collection of Mrs. A.T. Slosson, 26226 ( AMNH); [Coos Co.], Pinkham Notch, White M[oun]t[ain]s, [44°15' N, 71°15' W], 21–22. viii.1945, 1 ♂, JSS#11461, J.C. Bradley, Frank M. Hull Collection CNC 1973 ( CNC); [Grafton Co.], Franconia, [44°14' N, 71°45' W], 1Ψ, JSS#11507, Mrs. Slosson ( USNM); Carr[oll] Co., 2 mi [les] NW Wonalancet, [43°56' N, 71°24' W], Malaise trap, 8–14. vi.1984, 2 ♂♂, 5ΨΨ, JSS#11793–11796, 11808, 11810, 11828, D.S. Chandler ( DENH); Carr[oll] Co., The Bowl, 2.5 mi[les] NW Wonalancet, [43°56' N, 71°24' W], Malaise trap, 5–8. vi.1984, 2 ♂♂, 5ΨΨ, JSS#11789–11791, 11812, 11814–5, 11826, 9–14. vi.1984, 2 ♂♂, 6ΨΨ, JSS#11811,11816, 11818­22, 11827, 15– 20. vi.1984, 4 ΨΨ, JSS#11797­8, 11823­4, 20–26. vii.1984, 1 ♂, JSS#11832, 21–27. vi.1984, 1 ♂, JSS#11806 [3 legs and tergites 2 and 3 removed for DNA extraction], 1Ψ, JSS#11799 [3 legs removed for DNA extraction], 6ΨΨ, JSS#11800­5, 5–14. vi.1985, 2 ΨΨ, JSS#11846, 11848, 23.v.–4. vi.1985, 1 ♂, JSS#11849, D.S. Chandler ( DENH); Carr[oll] Co., 1 mi [le] N Wonalancet E Fk. Spring Brk., [43°54' N, 71°21' W], 1900', [579 m], Malaise trap, 5– 14. vi.1985, 1 ♂, 23.v.–4. vi.1985, 5 ♂♂, JSS#11840–11844, 5–14. vi.1985, 1 ♂, JSS#11839, D.S. Chandler ( DENH); Straf[ford] Co., 4 mi [les] W Durham, [43°08' N, 70°56' W], Malaise trap, 24–28. v.1982, 1 ♂, JSS#11787, 24–25. v.1982, 1 ♂, JSS#11834, R.M. Reeves ( DENH); Straf[ford] Co., Spruce Hole, 3 mi [les] SW Durham, [43°08' N, 70°56' W], Malaise trap, 11–18. vi.1987, 1 ♂, JSS#11835, D.C. Chandler ( DENH); [Cheshire Co.], M[oun]t Monadnock, [42°52' N, 72°07' W], 11. vi.1932, 3 ♂♂, A.L. Melander, A.L. Melander collection 1961, JSS#11466, 11468–11469 ( USNM); New York: Essex Co., M[oun]t Hurricane, [44°14' N, 73°43' W], vi.1939, 1 ♂, JSS#11467, R.C. Shannon ( USNM); Pennsylvania: [Lackawanna Co.], Spring Br[ook], [41°18' N, 75°36' W], 17. v.1945, 1 ♂, JSS#11464 [epandrium broken in half, surstyli separated], DDT Expt. ( USNM); Dauphin Co., Hershey, [40°17' N, 76°39' W], 1. vi.1974, 1 ♂, CMNH #352737 ( CMNH); [Philadelphia Co.], Roxborough, [40°02' N, 75°13' W], 10. vi.1911, 1 ♂, JSS#11465 ( USNM).

Description: Male: Body length 5.1–8.5 mm. Head: Holoptic, eyes joined for approximately two to four times the length of ocellar triangle, H:O 2.27–3.83:1. Arista black with yellow base. 1st flagellomere yellow. Pedicel yellow with 20–28 bristles along distal margin. Scape yellow with 5–8 dorsal bristles. Labellum and palps yellow. Occiput silver­pubescent with multiple rows of white hairs. Thorax: Proepisternum with a fan of 9–15 bristles. Postpronotal lobe yellow with 5–7 yellow hairs on posterior edge. Scutum rarely entirely brown, usually black dorsally, yellow laterally, with sharply to ill­defined boundaries between the colours ( Fig. 1 D, E); with dorsocentral and intra­alar rows of short hairs, dorsocentrals increasing in size posteriorly and terminating in 1–2 strong setae. Notopleuron with 2 setae and numerous smaller hairs. 1 posterior supra­alar seta. Postalar callus with 2–4 setae and 6–7 other moderately strong bristles. Scutellum yellow ( Fig. 1 B), rarely brownish along anterior margin to entirely brown in two specimens (JSS#11461 and 11832); with 2–4 pairs of strong posterior setae and numerous small black bristles over entire surface. Pleuron rarely entirely brown; usually mostly yellow, black on proepisternum, basal four fifths of katepisternum and meron, all but edges of anepisternum, small sclerite below wing base, subscutellum, and in a thin band posterior to posterior spiracle. Halter yellow. Legs: long and slender, usually entirely yellow, occasionally with brown coxae and slightly darkened posterior surface of femur; hairs and sockets on coxae usually yellow, rarely pale brown; hairs on trochanters and femora yellow to dark brown; tibiae and tarsi with yellow to black hairs with black sockets. Fore and mid­tibiae slender and slightly arched dorsoventrally; hind tibia narrow on basal third, broader towards tip, laterally arched in apical half (in dorsal view); apex with circlet of stiff yellow bristles all about the same length ( Fig. 2 C). Trochanters with 1–4 dorsomedial bristles and a loosely organized double row of shorter ventral bristles, most prominent on rear trochanter. Wings: Length: 5.4–9.3 mm; fourth costal section about 2–3 times as long as third, C4:C3 2.2– 3.5:1; R­M situated between basal one­third to nearly middle of discal medial cell (dm), S3:S2 2.1–2.7:1. Cell r1 bare basally; Sc usually mostly bare, microtrichose in distal corner only, occasionally microtrichose to level of junction of r and Sc; cell bm mostly bare, microtrichose along distal edge only. Tegula with 4–13 black bristles. Abdomen: Colour variable, almost entirely brown in many specimens ( Fig. 1 D, E); tergites 1–6 often brown with yellow along posterior edge and laterally; tergite 1 always has yellow anterolateral area. Sternites 1–5 yellow to brown. Tergite 1 with 9–15 large yellowish bristles. Tergite 7 and syntergosternite 8 brown to yellow. All hairs yellow. Genitalia: Epandrium and terminalia dark brown to yellow, phallus black . Epandrium nearly as long as wide, WE:LE 1.1– 1.4 (1.6):1. Surstyli asymmetrical; with upper lobes both projecting, upper lobe of right surstylus longest and deflected ventrally at 90 degrees, tapering uniformly to tip ( Fig. 11 A, B); middle lobe of right surstylus stubby, with rounded tip and curving medial edge, with no similar structure on left surstylus ( Fig. 11 C). Distiphallus with numerous, robust spines on first loop ( Fig. 11 A–C). Female: As male except: Ovipositor short, upcurved, 0.86– 1.09 mm ( Fig. 4 E). OL:PL 1.26–1.41:1; BL:OL 5.93–7.61:1; B:PL 0.30–0.45:1.

Distribution: Known from 89 specimens collected in a narrow latitudinal band (40º to 48º N in the east, 51º to 53.5º N in the west) between Maine and Alberta ( Fig. 12 ). Only two specimens are known from west of Lake Superior, both in Alberta.

Comments: This is one of the most common Nearctic species of Nephrocerus . General colouration is variable with what appears to be a pale and a dark morph. Most specimens have a predominantly yellow thorax with a contrasting black scutum but three specimens are almost entirely brown (JSS#11461, 11490 and 11832) and many have an entirely brown abdomen. These dark specimens all occur late in the season (3.vii.1968, 20–26.vii.1984 and 21–22.vii.1945). Dark morph individuals occur and may predominate in late or early season generations of some multivoltine species (for examples in Syrphidae see Dusek & Laska (1973) and Holloway et al. (1997)). The primary flight period for N. slossonae is from May 17th to July 4th with most records between May 29th and June 25th. Late July and late August records suggests that N. slossonae has a partial 2nd generation.

Nephrocerus slossonae has been recorded from a variety of habitats including: hardwood forest, dry cedar forest, oak savanna and wet meadow. Specimens collected in Quebec at King Mountain and Masham Township were hilltopping.

The allotype female of N. slossonae (JSS#13450) was examined but is not included in the material examined list here since it is actually N. acanthostylus .

The drawing of Nephrocerus daeckei in the Manual of Nearctic Diptera ( Hardy 1987) , Fig. 53.7) is actually Nephrocerus slossonae .

Figures

FIGURE 1. Photographs of Nephrocerus species. Abbreviation: prepst = proepisternum. Scale bars = 1.0 mm. A. Nephrocerus acanthostylus, holotype, JSS # 15348, ♂, dorsal of head, thorax and base of abdomen. B. Nephrocerus slossonae, JSS # 11834, ♂, dorsal of head, thorax and base of abdomen. C. Nephrocerus acanthostylus, JSS # 13450, Ψ, left lateral. D. Nephrocerus slossonae, JSS # 11836, ♂, left lateral of head and thorax. E. ♂, Nephrocerus slossonae, JSS # 11490, left lateral of head and thorax.

FIGURE 2. Posterior view of distal region of right hind tibia, Nephrocerus species. Scale bars = 0.1 mm. A. Nephrocerus acanthostylus JSS # 13490. B. Nephrocerus corpulentus JSS # 11470. C. Nephrocerus slossonae JSS # 11827.

FIGURE 4. Left lateral of ovipositors of female Nephrocerus species. Abbreviations: B = length of ovipositor base; cerc = cercus; OL = ovipositor length; PL = piercer length; spt = spermatheca, S = sternite; T = tergite. Scale bars = 0.1 mm. A. Nephrocerus acanthostylus, JSS # 13477. B. Nephrocerus atrapilus, JSS # 13397. C. Nephrocerus corpulentus, JSS # 13365. D. Nephrocerus daeckei, JSS # 11407. E. Nephrocerus slossonae, JSS # 11795.

FIGURE 11. Male Nephrocerus slossonae terminalia, ejaculatory apodeme and sperm pump removed; all from JSS # 11409. Arrows indicate key features. Scale bars = 0.1 mm. A. left lateral. B. right lateral. C. dorsal. D. ventral, phallus removed.

FIGURE 12. Distribution of Nephrocerus slossonae.