Phytomyza persicae Frick, 1954

Lonsdale, Owen, 2021, Manual of North American Agromyzidae (Diptera, Schizophora), with revision of the fauna of the " Delmarva " states, ZooKeys 1051, pp. 1-481 : 1

Phytomyza persicae Frick

Figs 811-813

Phytomyza obscurella var. nigritella Zetterstedt. Misidentification. Frost 1924: 81.

Phytomyza persicae Frick, 1954: 369. Spencer 1969: 266; Spencer and Steyskal 1986b: 211; Scheffer and Lonsdale 2018: 88; Eiseman and Lonsdale 2018: 81.

Description.

Wing length 1.7-2.0 mm (♂), 1.8-2.2 (♀). Vein dm-m absent. Eye height divided by gena height: 3.5-5.9. First flagellomere rounded, narrow, slightly shorter than high, not much higher than pedicel. Posterior ocelli separated by at least 3 × their width. Ocellar triangle indistinct. Cheek narrow.

Chaetotaxy: One or two ori (anterior seta usually 1/2-length or smaller if present, but uncommonly up to 3/4 length); two ors. Ocellar and postocellar setae at least as long as fronto-orbitals. Four dorsocentrals, one presutural, decreasing in height anteriorly; only posterior seta large, with second from rear not more than 3/5 length. Three or four scattered rows of acrostichal setulae ending at level of posterior dorsocentral.

Colouration: Setae brown to dark brown with pale shine (not black). Head light brown to greyish with antenna (sometimes only first flagellomere), fronto-orbital plate, palpus, clypeus and ventral margin of gena dark brown; gena and postgena (at least below cheek) sometimes slightly yellowish; dark brown spot on ocellar tubercle sometimes not much darker than surrounding frons, but sometimes clearly darker and sometimes much enlarged with posterior margin extending to base of vertical setae; posterolateral corner of frons sometimes noticeably darker to base of outer or inner vertical. Thorax with faint greyish pruinosity that is denser dorsally and also less clearly present on remainder of body; pruinosity sometimes appearing coppery postsuturally. Halter white. Calypter margin and hairs brown. Legs mostly dark brown, apices of femora sometimes narrowly to more widely yellowish, tibiae sometimes slightly paler, at least apically on fore leg, and tarsi yellowish with apical segments darker. Abdomen brown.

Genitalia: (Figs 811-813 ) Inner lobe of hypandrium narrow and closely surrounding postgonite. Halves of basiphallus overlapping at base, but otherwise flat, parallel. Sclerites of hypophallus band-like, mostly parallel with apices slightly incurved. Paraphallus small, dark, band-like, directed dorsally to fuse to ventromedial margin of mesophallus. Mesophallus dark, subcylindrical and with slight medial constriction. Distiphallus entirely split, forming one pair of narrow and very elongate, looped arms; very dark, but apex paler with small, clear apical cup. Ejaculatory apodeme with dark, narrow stalk and broad fan-shaped blade.

Hosts.

Rosaceae - Prunus .

Distribution.

Canada: ON, NS*. USA: CT, MA, NY, OH, VA.

Type material.

Holotype: USA. OH: Erie Co., 15.viii.1952, peach leaves, A.C. Dowdy (1♂[only head, one leg and puparium remaining], USNM).

Paratypes examined.

Canada. ON: Fonthill, 18.viii.1950, W.L. Putnam, peach leaf miner, CNC480131 (1♀, CNC), Vineland Sta., 20.vi.1951, W.L. Putnam, peach, CNC480122 (1♂, CNC), 21.vi.1951, CNC480124, CNC480129 (1♂,1♀, CNC), 23.vi.1951, CNC480125-480128 (4♀, CNC), 25.vi.1951, CNC480130 (1♀, CNC), 26.vi.1951, CNC480120, CNC480121, CNC480123 (3♂, CNC). USA. OH: Berlin Heights, v.1952 (10♂ 1♀ 1?, USNM).

Additional material examined.

Canada. NS: CBHNt. Pk., Mackenzie Mtn., 400 m, birch and fir, 29.v.1984, B.E. Cooper, PG639848 , CNC480132 (1♂, CNC), 7.vi.1984, CNC480134 (1♂, CNC), CBHNt. Pk., North Mt. , 400 m, 9.vi.1984, B.E. Cooper, PG767865 , CNC480133 (1♂, CNC) . USA. CT: New haven, “1717”, W.E. Britton, larva coll., 6.viii.1917, in peach leaf, emerged 1.vii.1918 (1?, USNM), MA: Hampshire Co., Southampton , 37 Middle Rd. , 18.x.2013, C.S. Eiseman, ex. Prunus persica em. 21.iii.2014, #CSE1015, CNC384791 (1♂, CNC), OH: Erie Co. , 15.viii.1952, peach leaves, A.C. Dowdy (1♀, USNM), Wayne Co., 1944, Weaver, peach leaf miner, “6-5”, “6-16” (1♂ 1♀, USNM), VA: Winchester, 29.vii.1915, bred from peach foliage, quaintance No. 1481, E.B. Blakeslee (2♂ 1♀, USNM) .

Comments.

The long, dark, looped arm of the distiphallus is an unmistakable characteristic of Phytomyza persicae , and should be examined to confidently differentiate it from similar species such as the Ilex leaf miners, which are nearly identical externally. In Europe, the very similar P. heringiana Hendel occurs on apple ( Malus domestica ) ( Papp and Černý 2020: fig. 128).

Figures

Figures 811 - 813. Phytomyza persicae Frick, male genitalia 811 hypandrial complex, left lateral 812 phallus, ventral 813 hypandrium and postgonite, ventral.