Phytomyza avicursa, Lonsdale, 2021

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 avicursa sp. nov.

Figs 745-747

Description.

Wing length 2.4 mm. Vein dm-m absent. Eye height divided by gena height: 3.0. First flagellomere slightly enlarged and subrectangular, thick. Border of fronto-orbital plate not evident. Cheek distinct, deepest part of ring around eye, but anterior region of fronto-orbital plate also clearly visible laterally.

Chaetotaxy: Two ori on one side and one on the other; two ors. Four dorsocentrals, decreasing in height anteriorly with anterior seta nearly 1/2 length of posterior seta. Acrostichal setulae in two irregular rows to level of second dorsocentral that sometimes appear as three rows. Very few scattered intra-alar setulae.

Colouration: Head light yellow with back of head, ocellar spot, posterolateral corner of frons (enclosing base of vertical setae), antenna, palpus and clypeus dark brown; ocellar spot small but relatively broad, subquadrate. Thorax dark brown with greyish pruinosity. Wing veins light brown to brown. Halter white. Calypter margin white with hairs light brown. Legs dark brown with apices of femora light yellow for length less than apical width of femora, more faded on mid and hind legs. Abdomen dark brown.

Genitalia: (Figs 745-747 ) Hypandrial lobe narrow and transverse, following inner margin of postgonite. Postgonite large, strongly hooked anteriorly, broadly flattened behind apex and with one outer seta. Phallophorus fused to T-shaped basiphallus. Hypophallus membranous and with two overlapping transverse lobes. Paraphalli made up of two flattened, widely spaced plates that are perpendicular to basiphallus. Mesophallus not evident. Distiphallus shorter than paraphallus, cylindrical, slightly compressed dorsoventrally, with base widened in ventral view and narrower in profile; apex clear, membranous, enclosing inner-ventral sclerotisation.

Host.

Unknown.

Distribution.

USA: VA.

Etymology.

The specific name compounds the Latin for bird (avis) and run (cursus), referring to the type locality.

Type material.

Holotype: USA. VA: Fairfax Co., Turkey Run Park, 0.3 km W mouth Turkey Run, 38°58'N, 77°09.6'W, Malaise trap, river, 14-17.v.2006, D.R. Smith (1♂, USNM).

Comments.

While unremarkable externally, the elongate, T-shaped, and unusual flat basiphallus and short distiphallus of Phytomyza avicursa are highly unique and easily characterise this new species, which is currently known only from the holotype male. Also see comments for P. winkleri .

Figures

Figures 745 - 747. Phytomyza avicursa, sp. nov., male genitalia 745 hypandrium and postgonite, ventral 746 hypandrial complex, left lateral 747 phallus, ventral.