Argentinomyia bolivariensis ( Fluke, 1945 )

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 : 41-43

Argentinomyia bolivariensis ( Fluke, 1945)

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

( Figs 2D , 20 , 21 and 90B )

Melanostoma bolivariensis Fluke, 1945: 19 .

Type locality: Ecuador. Bolívar , Talahua . HOLOTYPE Male AMNH (Examined). Refs.: Fluke, 1945: 27 ( Fig. 29 , Head, lateral view, male) 29 ( Fig. 45 , male abdomen); 1957: 277 (Figs 97–98, male genitalia)

Rhysops bolivariensis . Fluke, 1957: 266

Rhysops bolivariensis . Thompson et al. 1976: 42

Argentinomyia bolivariensis . Thompson & Skevington, 2014: 98

Argentinomyia bolivariensis . Montoya 2016: 460

Argentinomyia bolivariensis . Marín-Armijos et al. 2017: 168

Type material. HOLOTYPE. Adult Male , ECUADOR. Bolívar, Hacienda Talahua , 3100 m, 28.iv.1939, F.M. and H. Brown ( AMNH) . ALLOTYPE. ECUADOR. Label with the same data as Holotype (1♀, AMNH) . PARATYPE. ECUADOR. Label with the same data as Holotype (22♁, 23♀, AMNH); …, (1♁, 1♀, USNM ENT 00058848 ); …, (1♁, USNM ENT 0143840 ) ; …, (9♁, 9♀, WIRC) .

Length (n= 4): Body, 7.1–8.5 mm; Wings, 8.6–9.3 mm.

Diagnosis. A dark species with even brown-yellowish pollen on face except near the antennae; thorax golden pilose on notopleuron and in the area dorsal to the postalar callus; pro- and mesotibiae without a dark median ring; abdominal maculae slender, elongated, about two and 1/2 times as long as wide on 3 rd tergum, female abdomen generally black covered by grey pollinosity, at most with small reddish maculae; surstylus with dorsal margin slightly concave and ventral margin slightly convex; aedeagal lobe with apex acute; cercus and surstylus yellow, yellow pilose; surstylus with dorsal margin slightly concave and ventral margin slightly convex, shorter than broad; hypandrium narrowed laterally towards the apex; aedeagal lobe with apex acute.

Redescription. MALE. Head ( Figs 2D , 20A ): Face black, nearly perpendicular, slightly projected forward, tubercle low but elongate, lateral ventral part of frontal triangle evenly brown pollinose and yellow pilose, mid-vitta broad, shining and bare; lateral golden pollinose. Frontal triangle shining, golden pollinose anteriorly, face yellow pilose. Frontal triangle covered with brown pollen, arch dorsally to antennae shining, bare. Gena thinly whitish pollinose and white pilose. Ocellar triangle very thinly brownish pollinose, pile black; occipital pile and pollen yellow, becoming white ventrally. Antennae reddish yellow, short, ratio 1.0:1.2:2.3, basoflagellomere slightly longer than the scape and pedicel together; scape darker, basoflagellomere darkened on dorsal 1/2 and orange ventrally, basoflagellomere apically rounded, arista long and black, bare. Thorax ( Figs 20B–C ): Black, mesonotum semishining metallic; covered with brown pollen and brownish pile of various lengths, the apical portion black, with two median whitish pollinose vittae on anterior half; pile long and yellow. Pleura coated with brownish pollen which is whitish posteriorly, yellow pilose, only brownish pilose on notopleuron and area dorsal to postalar callus. Scutellum with long black hairs, some very short golden hairs intermixed, fringe long and yellow. Wing ( Fig. 20C ): Slightly yellowish, stigma yellow, membrane microtrichose; calypter whitish, border brown, fringe yellow; plumula white; halter yellow, capitulum dark. Legs ( Fig. 20C ): Pro- and mesolegs brownish to black, profemur brownish basally and yellow on apical 1/2; metafemur and all tibia yellow apically; basal two segments of metatarsus and basal 1/2 of metatibia reddish to yellow, brownish pilose. In teneral specimens pro- and metalegs often entirely yellow. Pile long hairs yellow. Abdomen ( Fig. 20B ): Narrow, black with two pairs of narrow reddish lateral maculae; lateral sides of the 2 nd tergum with metallic and golden pollinose maculae; maculae on 3 rd tergum reaching from base to apical 1/2, maculae on 4 th tergum smaller, reaching from base to apical 1/3; white pollen on maculae; abdomen shining along sides; pile pale; sterna yellowish, with a broad, median, black vitta, yellow pilose; male genitalia: cercus and surstylus yellow, yellow pilose; surstylus in lateral view ( Fig. 21A ) with dorsal margin slightly concave and ventral margin slightly convex, shorter than broad; hypandrium in ventral view ( Fig. 21C ) narrowed laterally towards the apex; aedeagal lobe in ventral view ( Fig. 21C ) with apex acute.

FEMALE ( Figs 20D–F ). Similar to male except for usual sexual dimorphism and differing in the facial pollen being somewhat paler. Frontal triangle with a transverse band on lower 1/2, with a distinct depression in the middle, dorsal 1/2 nearly bare behind the antennal base. Frontal triangle at the vertex about 2 and 1.5 times as wide as the ocellar triangle. Mesonotal pile sparse and much shorter. Abdominal maculae often absent but when present, they show clearly reddish dashes converging posteriorly. Tergum 5 th without maculae. Legs yellow, metafemur often yellow on basal 1/4, tarsi brown on dorsal edge. Female of A. altissima differs from A. bolivariensis only in the darker legs and a pair of elongate triangular orange maculae from the 2 nd to 4 th terga in addition to smaller maculae on 5 th tergum. According to Fluke (1945), the female of A. browni is similar to or indistinguishable from A. bolivariensis but differs from it by the presence of a carinate face above the tubercle, characteristic of A. browni .

Taxonomic notes. Argentinomyia bolivariensis is similar in morphology to A. altissima and A. browni from which it differs in the following combination of characters: A dark species with even brown-yellowish pollen on face except near the antennae ( Figs 20A, C , D-F); thorax golden pilose on notopleuron and in the area dorsal to the postalar callus ( Figs 20B, E ); pro- and mesotibiae without a dark median ring ( Figs 20A, C , D-F); abdominal maculae slender, elongated, about two and 1/2 times as long as wide on 3 rd tergum, female abdomen generally black covered by grey pollinosity, at most with small reddish maculae ( Figs 20B, E ). Based on males, A. bolivariensis differs from A. altissima and A. browni in having the surstylus in lateral view ( Fig. 21A ) with dorsal margin slightly concave and ventral margin slightly convex [versus surstylus with dorsal and ventral margins slightly concave in A. browni ( Fig. 23A ); surstylus very elongated and widened ventrally, with a median sized extension in the dorsal margin in A. altissima ( Fig. 13A )]; aedeagal lobe in ventral view, with acute apex in A. bolivariensis ( Fig. 21C ) and A. browni ( Fig. 23C ) [versus aedeagal lobe hearth shape, with the apical margin concave in A. altissima ( Fig. 13C )] (see “differential diagnosis” under each species or key).

Comments. The Holotype specimen of M. bolivariensis is currently in the AMNH. Photos are available on their website AMNH: https://sci-web-001.amnh.org/imulive/iz.html?#details=ecatalogue. 10021683.

Geographical range. Argentinomyia bolivariensis (n= 68) is present throughout both slopes of the Central Cordillera in Colombia * (Antioquia) and Ecuador (Bolivar) ( Fig. 90B ). The species is endemic to the Northern Andes domain, distributed at middle and high altitudes (2680–3400 m) in the provinces: Cauca (2680–3400 m) and Magdalena (3057 m) .

Non-type material examined. COLOMBIA. Antioquia, Belmira, Páramo de Belmira , 6.707065, -75.714136, 3057 m, 5.iii.2009, A.L. Montoya, Net (1♁, CEUA 114294 ); Medellín, Corregimiento Las Palmas, 6,182 72, - 75,527 79, 2680 m, Net, 16.x.2011, I. Ceballos (1♁, CEUA 93077 ) .

Figures

FIGURE 2. Differences in head morphology, male: A. Argentinomyia rugosonasa, frontal view; Argentinomyia longicornis: B. lateral view; C. frontal view; D. Argentinomyia bolivariensis, frontal view.

FIGURE 13. Argentinomyia altissima (Fluke, 1945), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm. D–E. Natural habitus of a female specimen in Pumapaccha, Cuzco, Perú (iNaturalist catalogue number# 37168068; https://www.inaturalist.org/observations/37168068). Photo taken by ©Jared Shorma.

FIGURE 20. Argentinomyia bolivariensis (Fluke, 1945), male (USNM ENT 0144380): A. Head, frontal view; B. Dorsal view; C. Lateral view. Female (USNM ENT 00058848): D. Head, frontal view; E. Dorsal view; F. Lateral view. Scale bars: 5 mm.

FIGURE 21. Argentinomyia bolivariensis (Fluke, 1945), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 23. Argentinomyia browni (Fluke, 1945), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 29. Argentinomyia currani (Fluke, 1937), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 45. Argentinomyia longicornis (Walker, 1836), male genitalia. A. Whole genitalia, lateral view; B. Epandrium, dorsal view; C. Hypandrium, ventral view. Scale bars: 1 mm.

FIGURE 90. Geographical distribution of Argentinomyia species in the Tropical Andes.