Argentinomyia genus is found in the Neotropical Region only, except absent from the Chilean subregion. Argentinomyia species belongs to the subfamily Syrphinae (bare postpronotum), and have anterior anepisternum and metaepisternum bare, face and scutellum black in ground colour (some species with face partly yellow), eye bare, abdomen oval or with parallel sides, face with tubercle, straigth in profile not produced anteriorly, antennal pits separated, metasternum not reduced, and male legs simple without strong setae.
New description:
MALE.
Head: Face with facial tubercle, without grooves, shiny black medially, golden pollinose laterally with punctuation, with two dense white pollinose maculae on eye margin, yellow pilose; gena black, white pollinose posteriorly; frontal triangle shiny black, white pollinose posteriorly, golden pollinose; vertical triangle black, black pilose; holoptic, eye bare; antenna brown, scape elongate, about twice as long as pedicel, black pilose; occiput black, silver pollinose, white pilose.
Thorax: Scutum and scutellum shiny bronze black, golden pilose; scutum with the dorsomedial short whitish pollinose vittae; postpronotum bare; subscutellar fringe complete with golden pile. Pleuron shiny bronze black, golden pilose; anterior anepisternum and metaepisternum bare; metasternum not reduced, bare; calypter black, yellow medially; plumula white; halter yellowish; spiracular fringes white. Wing: Wing membrane mostly hyaline, yellowish anteriorly; broadly bare basally (cells R and BM bare), microtrichose apically. Alula broad, microtrichose. Legs: Entirely yellow-yellowish except four apical protarsomeres, three apical mesotarsomeres and three apical metatarsomeres brown, metafemur black on apical 1/2 or less, and metatibia black.
Abdomen: slightly spatulate, mostly black with long yellowish pile. Tergum 1 black, pollinose; tergum 2 black with two lateral elongate, narrow orangish vittate maculae (difficult to see in some specimens); tergum 3 black with two anteromedial oblique orange maculae; tergum 4 black with two anteromedial oblique metallic-orange maculae (sometimes only metallic); tergum 5 black.
FEMALE.
Similar to male except as follows: frons shiny black on anetriro 1/3, bronze pollinose on posterior 2/3, with two medial black pollinose maculae; scutal vittae longer and bluish; metafemur mostly black, yellow only on less than basal 1/4. Abdomen with maculae on terga 2 and 4 metallic, more obscure; maculae on tergum 3 less evident.
Argentinomyia longicornis (Walker, 1836).
Walker, F. (1836) Descriptions, & c. of the Diptera. Pp. 331-359. In: Curtis, J., Haliday, A.H., and Walker, F. Descriptions, & c. of the Insects collected by Captain P. P. King, R. N., F. R. S., in the Survey of the Straits of Magellan. Transactions of the Linnean Society of London 17, 315-359. [1836.07.09]
Species of Argentinomyia were described in several genera. Rhysops Williston, 1907, Braziliana Curran, 1925 and Allograptina Enderlein, 1938 are genus names synonymized under Argentinomyia.
Synonyms:
Pipiza longicornis Walker, 1836: 343.
Melanostoma longicornis Williston, 1888: 263.
Braziliana vittithorax Hull, 1937: 176.
unless otherwise stated