Argentinomyia aurifacies 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 : 33-35

Argentinomyia aurifacies Thompson & Montoya sp. nov.

Proposed standard English name: Golden-faced long-antennae flower fly.

Argentinomyia DR sp. 1 Thompson, unpublished

( Figs 14 , 15 and 95 )

Type material. HOLOTYPE. Adult Male, pinned, deposited at National Museum of Natural History. Original label: “ DOMINICAN REPUBLIC, La Compartición, Pico Duarte ” / “ P. N. Armando Bermúdez / 19,025 337, -70,99825, 3087m ” / “RD-255 / 1.vii.2004, D. Pérez “ HOLOTYPE / Argentinomyia aurifacies / Thompson & Montoya 2023” ( USNM 00038437). PARATYPES. DOMINICAN REPUBLIC. La Vega, La Compartición, Pico Duarte ” / “ P. N. Armando Bermúdez / 19,025 337, -70,99825, 3087m ” / “RD-255 / 1.vii.2004, D. Pérez (3♀ USNM ENT 00038440- 42 ); …, La Vega, Sabana Kelly (= Quéliz) / Valle Nuevo 18,750 116, -70,616826, 2294 m, / 2.iv.2003, D. Pérez, R. Bastardo, B. Hierro (4♀, USNM ENT 00038431-34 ) ; San Juan Sierra Neiba, Trail to Sabana del Silencio , 11km SSW de El Cercado / 18,666 667, -71,500000, 1700-1900 m, 10.vii.2006, N.E. Woodley (1♁, USNM ENT 01443646 ; Genitalia dissected) .

Length (n= 5): Body, 7.4–8.1 mm; Wings, 5.8– 4.5 mm.

Diagnosis. Face extensively covered by golden pollinose and pilose; female frontal triangle with a transversal golden-brownish pollinose band; metafemur yellow, only obscured on basal 2/6 and apical 1/6 or little more; surstylus in lateral view with dorsal and ventral margins approximately of the same width in the whole length.

Description (Holotype). MALE. Head ( Fig. 14A ): Face entirely gold, white pollinose, white to golden pilose; tubercle low, bare, area above the tubercle white pollinose. Frontal triangle silver pollinose laterally, golden pilose. Frontal triangle golden-grey pollinose, golden pilose. Gena black. Occiput black pilose dorsally, yellow grey ventrally.Antenna orange, yellowish, darker toward the end and dorsal on basoflagellomere, short, ratio 1.2:1.0:1.8, basoflagellomere as long as the scape and pedicel together, apically rounded; pile black, arista brown. Thorax ( Figs 14B–C ): Aeneous grey, yellow pilose and brownish pollinose, with three brownish vittae, a median slender brown vitta extending along the thorax and ending at the scutellum, in addition to lateral wider brownish vittae, widening towards the pronotum and narrowed posteriorly near the pre-scutellum; pleura shining aeneous, grey pollinose, pile yellowish and sparse; scutellum shining brassy to aeneous, golden pilose. Wing ( Fig. 14C ): Very lightly tinged with brown, stigma brownish, membrane microtrichose, except cell c bare on basal 1/2, cells bm, r and cua bare on basal 1/5, respectively, the apical margin of the wing to just past the end of the 3rd vein brownish, giving the impression of an elongated brown macula; calypter wholly brown; plumula white; halter white, capitulum white. Legs ( Fig. 14C ): Yellow, metafemur slightly obscured on apical 1/5 dorsally; first pro- and mesotarsi yellow, other segments brown, metatarsus brown; coxae yellow. Abdomen ( Fig. 14B ): Black, parallel-sides, 1 st tergum shining metallic aeneous-black; 2 nd tergum with shallow, diffuse, bluish metallic maculae; 3 rd and 4 th terga with rectangular maculae, extending to the apical 2/3, respectively; 5 th tergum with a pair of small lateral rounded maculae, reaching the 1/2 of the segment length; pile yellow, with some black pile in the anterior edge of each segment; male genitalia: surstylus in lateral view ( Fig. 15A ) with dorsal and ventral margins approximately of the same width in the whole length; hypandrium in ventral view ( Fig. 15C ) narrowed laterally towards the apex; aedeagal lobe in ventral view ( Fig. 15C ) circular, apex rounded.

FEMALE ( Figs 14D–F ): Similar to male except: for usual sexual dimorphism, but differing in thorax comparatively more bluish, lateral vittae slender; frontal triangle with a transversal golden-brownish pollinose band; abdomen mostly bluish, with a pair of apically rounded maculae on 3 rd to 4 th terga, reaching to the apical 1/2 of each segment and there is an additional small lateral rounded macula on 5 th tergum reaching apical 1/2.

Taxonomic notes. Argentinomyia aurifacies sp. nov. is similar in appearance to A. taina sp. nov. and A. praeusta but is easily distinguished from them by the face extensively covered by golden pollinose and pilose ( Fig. 14 A-B, D- E); female frontal triangle with a transversal golden-brownish pollinose band ( Figs 14 D-E); metafemur yellow, only obscured on basal 2/6 and apical 1/6 or little more ( Figs 14A, C , D-F); 3 rd and 4 th terga with rectangular maculae, extending to the apical 2/3, respectively; 5 th tergum with a pair of small lateral rounded maculae, reaching the 1/2 of the segment length ( Figs 14B, E ). In A. praeusta the female frontal triangle with a medial white pollinose vitta ( Figs 65 D-E); metafemur obscured on apical 1/3 or little more ( Figs 65A, C , D-F); 3 rd and 4 th terga with maculae extending to the apical 1/2; 5 th tergum without a pair of small lateral rounded maculae ( Figs 65B, E ). In A. taina sp. nov. the frontal triangle with transversal golden-brownish pollinose band touching slightly the sides of the eyes ( Figs 77 D-E); metatibia mostly brownish apically, yellow basally and slightly obscured on apical 1/5 dorsally ( Figs 77C, F ); 3 rd and 4 th terga with maculae extending to the apical 2/3; 5 th tergum with a pair of small lateral rounded maculae ( Figs 77B, E ). Based on males, Argentinomyia aurifacies sp. nov. differs from A. praeusta and A. taina sp. nov. in having the surstylus in lateral view ( Fig. 15A ) with dorsal and ventral margins approximately of the same width in the whole length [versus surstylus with dorsal margin slightly concave and ventral margin slightly convex in A. praeusta ( Fig. 66A ); surstylus very elongated and widened dorsally, with a small extension at the ventral margin in A. taina sp. nov. ( Fig. 78A )]; hypandrium in ventral view ( Fig. 15C ) narrowed laterally towards the apex [versus hypandrium expanded laterally towards the apex in A. praeusta ( Fig. 66C ) and A. taina sp. nov. ( Fig. 78C )] (see “diagnosis” under each species or key).

Etymology. The specific epithet “ aurifacies ” is an adjective derived from the Latin words “ aureus ”, “ aureo ”, denoting golden (Brown 1956: 28) and the Latin “ facies ”, countenance, external form, figure, or surface (Brown 1956: 313). This name refers to the golden face of this species.

Remarks. Our study indicates that Argentinomyia aurifacies sp. nov., A. taina sp. nov. and A. praeusta occur sympatrically throughout middle and high elevations in the Dominican Republic.

Geographical range. Argentinomyia aurifacies sp. nov. (n= 9) is exclusively known from the Cordillera Central in the Dominican Republic (La Compartición, La Vega, Sabana Kelly (= Quéliz) / Valle Nuevo, San Juan Sierra Neiba) ( Fig. 95 ). The species is endemic to the West Indies domain, distributed at middle and high altitudes (1700–3087 m) in the Hispaniola province. Argentinomyia aurifacies sp. nov. and A. taina sp. nov. seems to occur in a restricted range and are rather rare in collections when compared to A. praeusta , which is widespread and abundant.

Figures

FIGURE 14. Argentinomyia aurifacies sp. nov., male Holotype (USNM ENT 01443646): A. Head, frontal view; B. Dorsal view; C. Lateral view. Female (USNM ENT 00038431): D. Head, frontal view; E. Dorsal view; F. Lateral view. Scale bars: 5 mm.

FIGURE 15. Argentinomyia aurifacies sp. nov., male Holotype, genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 65. Argentinomyia praeusta (Loew, 1866), male (USNM ENT 01443776): A. Head, frontal view; B. Dorsal view; C. Lateral view. Female (USNM ENT 01443777): D. Head, frontal view; E. Dorsal view; F. Lateral view. Scale bars: 5 mm.

FIGURE 66. Argentinomyia praeusta (Loew, 1866), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 77. Argentinomyia taina sp. nov., male Holotype (USNM ENT 01443645): A. Head, frontal view; B. Dorsal view; C. Lateral view. Female (USNM ENT 01443644): D. Head, frontal view; E. Dorsal view; F. Lateral view. Scale bars: 5 mm.

FIGURE 78. Argentinomyia taina sp. nov., male Holotype, genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 95. Geographical distribution of Argentinomyia species in the West Indies and the Galápagos Islands.