Phytomyza aldrichi Spencer, 1986

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 aldrichi Spencer

Figs 732-734

Phytomyza aldrichi Spencer in Spencer and Steyskal 1986b: 309; Eiseman and Lonsdale 2018: 67.

Description.

Wing length 2.0-2.3 mm (♂), 2.5 mm (♀). Vein dm-m absent. Eye height divided by gena height: 3.1. Cheek short, but deep medially

Chaetotaxy: Two ori (posterior ori sometimes appearing as ors); one ors. Two irregular rows of acrostichal setulae, ending medially or near posterior dorsocentral. Very few intra-alar setulae anteriorly. Ocellar and postocellar setae subequal to fronto-orbitals. Four dorsocentral setae, decreasing in length anteriorly. Smaller medial presutural supra-alar present.

Colouration: Ocellar tubercle, back of head and palpus brown; clypeus brownish yellow to brown; posterior margin of frons dark brown lateral to base of outer vertical seta, and with faded spot behind base of inner vertical seta that may reach base of one or both verticals; first flagellomere and scape black; remainder of head light yellow (paler below antenna); base of fronto-orbitals sometimes with minute brown spot. Scutum dark brown with greyish pruinosity, with postpronotum, notopleuron and sometimes narrow to wide supra-alar region yellow, with small to large brownish medial spot on postpronotum. Scutellum brown with greyish pruinosity, excluding ill-defined yellow medial stripe that is constricted at midpoint; ON male with stripe nearly absent, most evident apically. Metanotum dark brown with katatergite at least partially yellow. Pleuron variable in colouration, darkest specimens being entirely dark brown with greyish pruinosity with dorsal margin of anepisternum narrowly yellow; paler specimens (ME male palest) with dorsum of katepisternum yellow (including base of seta in posterior mottled region), anepimeron mottled yellow, anepisternum yellowish brown with dorsal ¼ yellow, and posteromedial margin and large anteroventral spot darker brown. Halter white. Calypter margin and hairs brown. Legs variable in colouration, darkest specimens brown with knees broadly yellow; paler specimens with only base of coxae brown, tibiae paler, and sometimes femora with pale mottling. Abdomen dark brown.

Genitalia: (Figs 732-734 ) Hypandrium stout and broadly rounded, with inner lobes narrow, curved, joined medially and with two anterior setae. Postgonite dark, apically hooked, with one seta. Right 1/2 of basiphallus joined to dorsomedial margin of phallophorus; left side with ventrobasal process around shaft; rounded apically, nearly parallel-sided along length. Hypophallus membranous with one pair of flat, clavate laterobasal sclerites with outer margins subparallel. Mesophallus short, with narrow basal stem meeting duct; flanked by one pair of broad, rounded, flat paraphalli. Distiphallus with one pair of very narrow, dark, diverging tubules, subequal to length of mesophallus. Ejaculatory apodeme with stem short, with lateral subbasal swelling and blade broad with margins pointed.

Host.

Ranunculaceae - Ranunculus .

Distribution.

Canada: NS*, ON*, QC*. USA: ID, MD*, ME, OH.

Type material.

Holotype: USA. ID: Moscow, J.M. Aldrich (1♂ [head missing], USNM).

Additional material examined.

Canada. NS: Truro , 26.ix.1913, CNC480058 (1♂, CNC), ON: Marmora, 8.v.1952, J.C. Mitchell, CNC480059 (1♂, CNC), QC: Old Chelsea, 11.vi.1959, J.R. Vockeroth, CNC480057 (1♀, CNC) . USA. MD: Montgomery Co., Colesville, 26.vi.1977, Malaise trap, W.W. Wirth (1♂, USNM), ME: Washington Co., Perry, Birch Point, 15.vi.2014, C.S. Eiseman, ex. Ranunculus repens em. 29.vi.2014, #CSE1141, CNC384880 (1♂, CNC), OH: Hocking Co. , South Bloomingville , Deep Woods Farm, 6.viii.2016, C.S. Eiseman, Ranunculus recurvatus , em. 20.viii.2016, #CSE2927, CNC654479 (1♂, CNC) .

Comments.

Yellow shoulders and a medially yellow scutellum are diagnostic of this species, as is the short, dark, branched distiphallus and the broad, flat paraphallus.

Figures

Figures 732 - 734. Phytomyza aldrichi Spencer, male genitalia 732 hypandrial complex, left lateral 733 phallus, ventral 734 hypandrium and postgonite, ventral.