Phytobia setosa (Loew)

Figs 3, 124, 125, 683-688, 689

Agromyza setosa Loew, 1869: 45. Frick 1952a: 373.

Agromyza aceris Greene, 1917: 313. Frick 1952a: 390. Frick 1959 [synonymy not explicit].

Phytobia (Phytobia) setosa . Frick 1959: 376.

Phytobia setosa . Spencer 1969: 107; Spencer and Steyskal 1986b: 77.

Description

(Figs 3, 124, 125, 689). Wing length 3.4-4.6 mm (♂), 3.7-4.4 mm (♀). Length of ultimate section of vein M4 divided by penultimate section: 1.2-1.4. Costa extending to vein M. Eye height divided by gena height: 3.0-4.1. Frons soft if anterior margin orange. Space between antennae ~ 1/3-2/3 width of scape. Clypeus narrow, sides of buccal cavity parallel and length of epistoma 1/2 width. Space between cross-veins as long as dm-m.

Chaetotaxy: Two or three ori; two ors (anterior ors sometimes slightly inclinate). Orbital setulae reclinate, in a single irregular row. Postocellar and ocellar setae well-developed, subequal to fronto-orbitals. Small to weak seta medial to presutural supra-alar. Prescutellar acrostichal seta nearly as long as anterior dorsocentral. Two to three posteromedial setae on mid tibia.

Colouration: Body predominantly dark brown. Lunule orange. Frons slate-grey with posterolateral margin and anterior 1/3 or less sometimes orange; if frons between fronto-orbital plates partially orange, sides of face and gena orange to rusty with all or dorsal margin of gena grey and ventral margin brown. Antenna dark orange, distal margin of first flagellomere brownish (more so on outer face, particularly in individuals with entirely grey frons); uncommonly dark brown with base (more so on inner surface) conspicuously orange. Mid trochanter and coxa sometimes orange laterally. Halter yellow. Calypter margin and hairs dark brown. Abdomen with epandrium sometimes variably to entirely orange or reddish, brightest near base.

Genitalia: (Figs 683-688) Epandrium slightly produced ventrally. Surstylus separate from epandrium, small, heavily setose apically, directed inwards. Cercus narrow, setose. Hypandrium well-developed, with narrower, stout, rounded apex; inner lobe with several setae. Phallophorus small. Basiphallus narrowly sclerotised along dorsum, split apically with left process hook-like and right process abruptly paler on distal 1/2; halves flanking base of mesophallus. Hypophallus narrow, curved, longer than mesophallus. Mesophallus cylindrical with base rounded, slightly bent at midpoint, width ~ 1/3 length; dorsally fused to base of distiphallus. Distiphallus divided into one pair of long, slender tubules along most of length; evenly dark along length. Ejaculatory apodeme stout with rounded blade, short, apically widening stem and stout base; sperm pump with transverse sclerotised bar.

Hosts.

Sapindaceae - Acer rubrum, A. saccharum *.

Distribution.

Canada: NB*, NS*, ON, QC, SK*. USA: AZ*, CT*, DC, IA, IN, MA, MD, MI, NY, PA*, VA, WI, WV. Mexico (Durango).

Type material.

Holotype: [setosa]: USA. District of Columbia (1♂, MCZ; type No. 13442).

Holotype [ Agromyza aceris]: USA. VA: Falls Church, Chain Bridge, Acer rubrum, reared 26.iv.1916, "12973 Hopk US", C.T. Greene (1♀ 1puparium, USNM; type No. 21062).

Paratypes examined

[ Agromyza aceris]: USA. VA: Falls Church, Chain Bridge, Acer rubrum, reared 26.iv.1916, "12971-a Hopk US", Acer, C.T. Greene (1♂ 1puparium, USNM), WV: French Creek, F.E. Brooks, Quaintance No. 9444 (1♀, USNM).

Additional material examined.

Canada. NB: Kouchibouguac N.P., 10.vii.1977, J.F. McAlpine, Code 6025S, CNC391749 (1 ex [abdomen missing], CNC), 11.vii.1977, Code - 6026T, CNC391753 (1♀, CNC), 12.vii.1977, Code - 6041I, CNC391754 (1♀, CNC), 13.vii.1977, Code - 6042J, CNC391755 (1♀, CNC), Code - 6039G, CNC391756 (1♀, CNC), 8.vii.1977, Code - 6021O, CNC391752 (1♀, CNC), 15.vi.1978, S.J. Miller, Code - 7066T, CNC391811 (1♀, CNC), 18.v.1977, B. Cooper, Code - 5065U, CNC391744 (1♂, CNC), 20.v.1977, Code - 5097A, CNC391750, CNC391812 (2♀, CNC), 19.v.1977, W.P. Hanley, Code - 5087Q, CNC391748 (1 ex [abdomen missing], CNC), Code - 5098B, CNC391745, CNC391751 (1♂ 1♀, CNC), 6.vii.1977, NS: CBHNt. Pk., Mackenzie Mtn., 400 m, birch and fir, 1.vi.1984, B.E. Cooper, PG639848, CNC391765 (1♂, CNC), 27.v.1984, CNC391767 (1♂, CNC), 28.v.1984, CNC391769, CNC391814 (1♂, 1♀, CNC), 29.v.1984, CNC391768 (1♂, CNC), 30.v.1984, CNC391766 (1♂, CNC), 31.v.1984, CNC391770 (1♂, CNC), 7.vi.1984, CNC391813 (1♀, CNC), ON: Midland, 18.v.1976, J.T. Huber (1♂, DEBU), Guelph, 10.v.1982, A. John (1♂, DEBU), Essex Co., Windsor, ~ 1.5 km S Ojibway Prairie, 5-12.vi.2001, private prairie, Malaise, S. Paiero (1♂, USNM), Bell’s Cor., 1.v.1951, J.F. McAlpine, CNC391732 (1♂, CNC), Greenbush, at lights, 6.v.1999, R. Hainault, CNC391807 (1♀, CNC), Lanark Co., N. Burgess Twp., 15.v.1971, D.M. Wood, CNC391808-391810 (3♀, CNC), Marmora, 25.iv.1952, J.F. McAlpine, CNC391734 (1♂, CNC), 28.iv.1952, CNC391757 (1♀, CNC), 29.iv.1952, CNC391733 (1♂, CNC), Metcalfe, 12.v.1983, B.E. Cooper, CNC391785 (1♂, CNC), 14.v.1994, CNC391788, CNC391789 (2♂, CNC), 17.v.1994, CNC391786, CNC391787 (2♂, CNC), 7.v.1994, CNC391791 (1♂, CNC), 8.v.1994, CNC391790 (1♂, CNC), Midland, 5.v.1959, J.G. Chillcott, CNC391780 (1♂, CNC), Normandale, 42°42'N, 80°19'W, 22.v.1956, J.R. Vockeroth, CNC391730, CNC391731 (2♂, CNC), Ottawa, 9.v.1923, C.H. Curran, CNC391740 (1♂, CNC), Rockport, 9.v.1961, J.R. Vockeroth, CNC391781 (1♂, CNC), QC: Abbotsford, 22.v.1936, G.E. Shewell, CNC391758 (1♀, CNC), Beechgrove, 45°39'N, 76°8'W, 10.v.1962, J.R. Vockeroth, CNC391727-391729 (3♂, CNC), 15.v.1961, CNC391723 (1♂, CNC), 16.v.1962, CNC391724-391726, CNC391760 (3♂, 1♀, CNC), Chelsea, 24.iv.1933, G.S. Walley, CNC391741 (2♂ / ♀, CNC), Duncan Lake, nr. Rupert, 21.v.1971, J.F. McAlpine, CNC391793, CNC391794, CNC391762-391764, CNC391802, CNC391805, CNC391806 (3♂ 5♀, CNC), 29.v.1971, CNC391792, CNC391795-391801, CNC391803 (9♀, CNC), 5.vi.1971, CNC391804 (1♀, CNC), Gatineau Pk., Harrington Lk., 31.v.1954, E.E. Sterns, CNC391759 (1♀, CNC), Gatineau Pk., Lac Philippe, 23.v.2011, O. Lonsdale, CNC391779 (1♂, CNC), Hull, 22.v.1923, R. Ozburn, CNC391720 (1♂, CNC), 26.iv.1929, C.H. Curran, CNC391707 (1♂, CNC), Kingsmere, 12.v.1958, J.G. Chillcott, CNC391721, CNC391722 (2♂, CNC), Lac Mondor, Ste. Flore, 21.v.1951, E.G. Munroe, CNC391746 (1♂, CNC), 5.v.1951, CNC391713, CNC391714 (2♂, CNC), 5.vi.1951, CNC391717 (1♂, CNC), 6.v.1951, CNC391708-391712, CNC391715, CNC391716, CNC391718 (8♂, CNC), Lac Philippe, 75°36'N, 76°0'W, 25.iv.1987, J.R. Vockeroth, CNC391773, CNC391777 (2♂, CNC), Mt. St. Hilaire, North Ck., 3-6.v.1982, B.M. Nelson, CNC391771, CNC391772, CNC391774-391776 (5♂, CNC), Old Chelsea, 17.v.1947, G.E. Shewell, CNC391735-391739 (5♂, CNC), 17.v.1990, J.R. Vockeroth, CNC391778 (1♂, CNC), Tetreau val, 20.v.1923, C.H. Curran, CNC391719 (1♂, CNC), SK: Sask. Landing, 50°39'N, 107°56'W, 25.v.1955, J.R. Vockeroth, CNC391761 (1♂, CNC) . USA. AZ: Portal SW Res. Sta., 5-9.vi.1972, Malaise trap, W.W. Wirth (1♂, USNM), CT: Redding, 19.v.1934, A.L. Melander (1♂, USNM), IN: Lafayette, 1.iv.1918, J.M. Aldrich (1♂, USNM), MA: Petersham, 2.vi.1914, A.L. Melander (1♂, USNM), Woods Hole, 20-30.vi.1923, A.H. Sturtevant (1♀, USNM), New Bedford, 25.iv, A.L. Melander (1♀, USNM), Boston, A.L. Melander, May (1♂, USNM), June (1♀, USNM), MD: near Plummers Isl., 7.iv.1915, R.C. Shannon (1♂, USNM), Montgomery Co., Clarksburg, 20-22.v.1988, W.E. Steiner and J.M. Swearingen (1♂, USNM), Bethseda, 5.v.1969, G. Steyskal (2♂, USNM), Colesville, 21.iv.1977, W.W. Wirth (1♂, USNM), Bethseda, 27.iv.1969, W.W. Wirth (1♂, USNM), Prince Georges Co., 7.v.1977, J.F. Reinert (1♂, USNM), MI: Otsego Co., 26.iv.1941, R.R. Dreisbach (1♂, USNM), NY: Savage Rt. Pond, 3mi W Geneva, Knutson, pupa coll. 21.iii.1966, emerged 2.iv (1♂ [with puparium], USNM), W Nyack, 31.v.1936, A.L. Melander (2♂, USNM), Long Island, 17.ix.1988, R. Latham (1♂, USNM), Long Island, Orient., R. Latham, 6.viii.1952 (1♀, USNM), 4.ix.1962 (1♀, USNM), PA: Sullivan Co., Wyoming State For., 8 km NW Laporte, 6.v.1987, J.M. Cumming, CNC391782-391784 (3♂, CNC), VA: Fairfax Co., Great Falls Park, quarry, 38°59.1'N, 77°14.8'W, Malaise trap, D.R. Smith, 3-10.v.2007 (1♂ 1♀, USNM), 10-17.v.2007 (1♀, USNM), 24.iv-2.v.2007 (1♀, USNM), WI: Sawyer Co., 7.v.1964, J.B. Hanson, ex. sugar maple root (1♂ 1♀, USNM). Location unknown. "Mel. It. / v.18.10", CNC391742 (2♂ / ♀, CNC), 3-51Y / BRI-97 / 75-714, CNC391747 (1♂, CNC) .

Comments.

Feeding on relatively widespread and abundant hosts, Acer rubrum and A. saccharum, Phytobia setosa is encountered with relative frequency east of Manitoba and New Mexico and is often well-represented in collections. External and male genitalic morphology strongly resembles that of the sometimes similarly large Phytobia amelanchieris, especially in those P. setosa with the anterior ors slightly inclinate, but P. amelanchieris often has more slender fronto-orbitals with the ori and ors always clearly differentiated, and the sides of the buccal cavity are slightly convergent anteriorly.