Argentinomyia plaumanni Thompson & Montoya, 2023

Montoya, Augusto L. & Wolff, Marta, 2023, Taxonomic revision of the Neotropical genus Argentinomyia Lynch-Arribálzaga, 1891 (Diptera: Syrphidae), with description of 16 new species, Zootaxa 5234 (1), pp. 1-157 : 105-106

Argentinomyia plaumanni Thompson & Montoya sp. nov.

Proposed standard English name: Plaumanni’s long-antennae flower fly.

Argentinomyia 74–06 Thompson, unpublished

( Figs 61 , 62 and 93D )

Type material. HOLOTYPE. Adult male, pinned, deposited at National Museum of Natural History. Original label: “ BRASIL, Santa Catarina, Nova Teutonia” / “ -27,183334, -52,383334, 857m 10.i.1965, F. Plaumann ” “ HOLOTYPE / Argentinomyia plaumanni / Thompson & Montoya 2023” ( USNM ENT 00036936 ). Identified as Argentinomyia 74–06 by Thompson 1974 . PARATYPES. BRAZIL. Labels : same data as Holotype (7♁, USNM ENT 00036934 ; 00036931; 00036932; 00036937; 00036933; 00036935; 0036938) ; BRASIL. Curitiba , 3.i.1954, N.L.H. Krauss (1♁, USNM ENT 01443774 , dissected) .

Length (n= 5): Body, 8.6–9.1 mm; Wings, 7.2–7.4 mm.

Diagnosis. Legs black to brownish; except femur yellow on apical 1/4; pro-, meso- and metatibia yellow on basal 1/3, 1/4 and 1/2, respectively, tarsus black; black pilose; abdomen black, 2 nd tergum with a pair of basolateral elongate yellow maculae reaching the apical 3/4 of the segment length; 3 rd tergum with a pair of basal elongated maculae reaching apical 2/3, but not reaching lateral margin; 4 th and 5 th terga black; surstylus with dorsal margin slightly concave and ventral margin slightly convex.

Description. MALE. Head ( Fig. 61A ): Face perpendicular with four faint transverse depressions, tubercle elongate, broad and low; mid-vitta shining black, sides white pollinose and pilose. Frontal triangle shiny, coppery pollinose, black pilose. Gena shining, white pollinose. Ocellar triangle black, black pilose; occipital pile fine, short and black, white pollinose. Antennae orange, short, ratio 1.2:1.0:2.0; scape darker, basoflagellomere darkened dorsally, scape only very little longer than pedicel which is wider than long, basoflagellomere short, little longer than the scape and pedicel together; arista yellow at base and dark on apical third. Thorax ( Figs 61B–C ): Aeneous, scutum with two very faint pollinose white vittae on anterior half, yellow-golden pilose. Pleura lightly coated with brownish to rusty-colored pollen, yellow pilose. Scutellum black, with long golden pile, in addition to some brown pile in the margin. Wing ( Fig. 61C ): Slightly yellowish, stigma yellow, microtrichose, except bare on basal 1/4 of cell bm, cell cua bare basally; calypter wholly whitish; plumula yellow; halter yellow, capitulum yellow. Legs ( Fig. 61C ): Black to brownish; except femur yellow on apical 1/4; pro-, meso- and metatibia yellow on basal 1/3, 1/4 and 1/2, respectively, tarsus black., black pilose. Abdomen ( Fig. 61B ): Narrow with nearly parallel sides, shining black, 2 nd tergum with a pair of basolateral elongate yellow maculae reaching the apical 3/4 of the segment length; 3 rd tergum with a pair of basal elongated maculae reaching apical 2/3, but not reaching lateral margin; 4 th and 5 th terga black, black pilose, sterna yellow pilose; male genitalia: surstylus in lateral view ( Fig. 62A ) with dorsal margin slightly concave and ventral margin slightly convex, shorter than broad; hypandrium in ventral view ( Fig. 62C ) narrowed laterally towards the apex; aedeagal lobe in ventral view ( Fig. 62C ) circular, apex rounded.

FEMALE. Unknown.

Taxonomic notes. Argentinomyia plaumanni sp. nov. is similar to A. nigrans differing by the following combination characters: Legs black to brownish; except femur yellow on apical 1/4; pro-, meso- and metatibia yellow on basal 1/3, 1/4 and 1/2, respectively, tarsus black, black pilose ( Figs 61A, C, D, F ); 2 nd tergum with a pair of basolateral elongate yellow maculae reaching the apical 3/4 of the segment length ( Figs 61B, E ). In A. nigrans the femora and tarsi black ( Figs 53A, C, D, F ); abdomen black with small yellow to red maculae on basal corners of the 2 nd tergum, reaching over the sides and 1/2 of segment length ( Figs 53B, E ). Based on males, A. plaumanni sp. nov. differs from A nigrans in having the surstylus in lateral view ( Fig. 62A ) with dorsal margin slightly concave and ventral margin slightly convex [versus surstylus with dorsal and ventral margins similar (square-like) in A nigrans ( Fig. 54A )] (see “diagnosis” under each species or key).

Etymology. The specific epithet of this species is a Latinized noun in the genitive case of the last name ‘Plaumann’ in honor of Fritz Plaumann, who collected the type series in Nova Teutonia.

Geographical range. Argentinomyia plaumanni sp. nov. (n= 9) is exclusively known from southeastern Brazil (Santa Catarina and Paraná) ( Fig. 93D ). The species is endemic to the Paraná domain at low altitudes (857 m) in the Paraná Forest province .

Figures

FIGURE 53. Argentinomyia nigrans (Fluke, 1945), male (USNM ENT 01384670): A. Head, frontal view; B. Dorsal view; C. Lateral view. Female (USNM ENT 01406441): D. Head, frontal view; E. Dorsal view; F. Lateral view. Scale bars: 5 mm.

FIGURE 54. Argentinomyia nigrans (Fluke, 1945), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm. D–G. Rhysops funerea (Hull, 1949), male Holotype (CNC DIPTERA 169358). D. Latero–frontal view; E. Dorsal view; F. Lateral view; G. Label.

FIGURE 61. Argentinomyia plaumanni sp. nov., male Holotype (USNM ENT 00036936): A. Head, frontal view; B. Dorsal view; C. Lateral view. Scale bars: 5 mm.

FIGURE 62. Argentinomyia plaumanni sp. nov. male Holotype, genitalia. A., Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 93. Geographical distribution of Argentinomyia species in the North Andes and southeastern South America.