Melanagromyza glyptos, 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

Melanagromyza glyptos sp. nov.

Figs 54 , 55 , 281-284

Description

(Figs 54 , 55 ). Wing length 3.6-3.9 mm (♂), 3.1-3.4 mm (♀). Length of ultimate section of vein M4 divided by penultimate section: 0.6-0.7. Eye height divided by gena height: 2.4-4.9. Gena angled dorsally on anterior 1/2, highest near midpoint. Fronto-orbital plate and parafacial broadly visible laterally, continuing under eye as distinct cheek; fronto-orbital plate well-developed, setae slightly inset. Clypeus narrowed and slightly truncated medially, sides bowed outwards. Sides of ocellar triangle shallowly concave. Parafacial and ocellar triangle subshiny.

Chaetotaxy: Three or four ori, sometimes with slightly larger gap between anterior two setae; two ors. Orbital setulae dense, in several irregular rows, reclinate to erect. Ocellar setulae erect. Eye broadly pilose dorsomedially. Third dorsocentral (variable from slightly longer than setulae to 2/3 length of second dc) sometimes present directly in front of second dorsocentral in male. Acrostichal setulae in eight irregular rows. Mid tibia with two posteromedial setae.

Colouration: Body, including halter, dark brown in base colour. Scutum shiny with faint greenish reflection. Calypter margin and hairs white. Abdomen (excluding tergite 1) sometimes coppery, with light blue shine usually evident posteriorly.

Genitalia: (Figs 281-284 ) Epandrium with small posterodistal spine. Hypandrium with apex strongly produced as apodeme. Metepiphallus with serrated ridges, one pair of longer ventral spines, and several overlapping lateral ridges. Proepiphallus V-shaped, narrowly divided medially and with apex upcurved. Basiphallus U-shaped with sides diverging and tips irregular in outline. Distiphallus separated from phallophorus by less than height of basiphallus; high, with spinulose internal structures, apex abruptly truncated, sides subparallel, and with short, thin bifid ventroapical plate; lateral surface of distiphallus with raised plate bearing minute scales and ridges; mesophallus projecting basally from distiphallus and far exceeding basal margin of distiphallus.

Variation: Male from Plummers Island differs as follows: two ori; frons with several longitudinal wrinkles on each side of ocellar triangle; wing length 3.5 mm; length of ultimate section of vein M4 divided by penultimate section 0.5; eye height divided by gena height: 4.8; abdomen with light blue shine; lateral margin of basiphallus less sculptured; lateral plate on dorsal lobe of distiphallus less pronounced, without medial scales. Several specimens from Turkey Run with wing length 3.0-3.2 mm (♂), 3.4 mm (♀), abdomen and notum distinctly green with apex of abdomen bluish, and phallus slightly smaller and paler.

Host.

Unknown.

Distribution.

USA: MD, SC, VA.

Etymology.

Melanagromyza Gr. glyptos for carved, referring to sculptured outer lateral surface of distiphallus.

Type material.

Holotype: USA. NC: Buncombe Co., 4 km SW Black Mtn., 21-27.1986, W.E. Steiner, Malaise trap, mixed deciduous and hemlock forest nr. small stream (1♂, USNM).

Paratypes: USA. MD: Montgomery Co., Plummers Island, 38°58'N, 77°10'W, Malaise trap, lower trap, 24.iv-7.v.2006, D.R. Smith and J.W. Brown (1♂ 1♀, USNM; 1♀, CNC), Plummers Isl., 11.vii.1915, R.C. Shannon (1♂, USNM). VA: Shenandoah, Lewis Falls, 4.vii.1939, A.L. Melander (1♂, USNM), Fairfax Co., Turkey Run Park, nr. mouth of Turkey Run, 38°57.9'N, 7°09.4'W, Malaise trap, D.R. Smith, 29.iii-25.iv.2005 (1♂ 5♀, USNM; 1♂, CNC), 26.iv-2.v.2007 (12♂ 9♀, USNM), river, 14-17.v.2006 (2♀, USNM), Turkey Run Park, nr. headquarters bldg. 38°57.7'N, 77°08.9'N, Malaise trap, 29.iii-17.iv.2007, D.R. Smith (2♂ 1♀, USNM; 1♂, CNC), Great Falls Park, swamp trail, 38°59.4'N, 77°15.2'W, Malaise trap, 24.iv-2.v.2007, D.R. Smith (1♂, USNM; 1♀, CNC), Shenandoah, N Park Pinnacles, 19.vii.1952, W.W. Wirth (1♂, USNM).

Comments.

Melanagromyza glyptos and M. diantherae are superficially similar, being large and stout-bodied with a blue metallic shine and more than five fronto-orbital setae. The two species are otherwise quite different in both outward and genitalic morphology, and can be easily diagnosed using the characters listed in the key.

Figures

Figures 52 - 63. Melanagromyza buccalis Spencer, head 52 anterior 53 lateral 54, 55 M. glyptos sp. nov., head 54 anterior 55 lateral 56, 57 M. virens (Loew), head 56 anterior 57 lateral 58, 59 M. virginiensis Spencer, head 58 anterior 59 lateral 60 Melanagromyza sp., female (S. A. Marshall - Cuba) 61 Melanagromyza sp., female (S. A. Marshall - Ontario, Hornings Mills) 62, 63 M. virens (Loew), lectotype, head 62 anterolateral 63 lateral.

Figures 281 - 284. Melanagromyza glyptos Lonsdale, sp. nov., male genitalia 281 external components, ventral 282 hypandrium, ventral 283 hypandrial complex, left lateral 284 phallus and epiphallus, ventral.