Talahua fervida Fluke, 1945

Montoya, Augusto L. & Wolff, Marta, 2020, Description of six new large species of Argentinomyia Lynch-Arribalzaga, 1891 and redescription of Talahua fervida (Fluke, 1945) (Diptera, Syrphidae, Syrphinae), ZooKeys 929, pp. 19-51 : 19

Talahua fervida Fluke, 1945 Figures 12 , 13 , 14 , 17

Melanostoma fervidum : Fluke (1945: 22).

Talahua fervidum : Fluke (1957: 262).

Talahua fervida : Thompson et al. 1976: 45 (catalog citation); Thompson 1999: 338 (catalog and taxonomic notes); Mengual et al. 2008: 545 (taxonomic list); Montoya 2016: 462 (catalog citation); Marín-Armijos et al. 2017: 184 (catalog citation).

Type specimen of

Talahua fervida

Fluke 1945.

Holotype. ♂, ECUADOR, Bolívar, Hda. Talahua . Original label: "ECUADOR, Bolivar, Hda. [Hacienda] Talahua , 3100 m a.s.l., 28.iv.1939, F.M. Brown & H. Brown collectors, AMNH". / Melanostoma / ( Talahua ) / fervidum / Fluke" [red, handwritten except first line]". The holotype is deposited at the AMNH in New York, USA. Paratype 3 ♂, same information as holotype, deposited in the AMNH, USNM, and WIRC (http://research.amnh.org/iz/types_db/details.php?specimen_id=2724, http://syrphidae.myspecies.info/taxonomy/term/140).

Genus differential diagnosis

(modified from Fluke 1945, Thompson and Skevington 2014). Male dichoptic. Both sexes with face slightly receding to perpendicular with a well-rounded tubercle, facial pollinosity yellowish (broadly punctuate in the Platycheirus stegnus species group or Carposcalis subgenus as well as some Argentinomyia species), never with transversal grooves dorsally along tubercle (present in some Argentinomyia ); antennal pits distinctly separated (confluent in Xanthandrus ); basoflagellomere large, slightly oval and apically rounded, scape broader than long, nearly equal to pedicel; metespisternum bare (with several fine subappressed hairs in Xanthandrus ); katepisternal pile patches broadly separated throughout (broadly separated posteriorly, joined anteriorly in Xanthandrus ); metasternum entire (greatly reduced in Melanostoma ), bare; mesocoxa pilose posteriorly (bare in Argentinomyia and Melanostoma ); metacoxa with a tuft of pile at posteromedial apical angle (bare in Argentinomyia ); scutellum with a deep groove next to the rim (present in the new large Argentinomyia species described here); wing without maculae along the anterior edge of apical marginal cells; male legs, simple, slender, without bristles, pile tufts or modified hairs (modified, either broadened, or with special bristles, pile tufts or modified hairs as in Platycheirus and some Tuberculanostoma ); tibiae usually yellow with a dark ring near the middle, more prominent on the metalegs; abdomen elongated or with parallel sides, with 4 to 5 pairs of large rounded to triangular maculae; male genitalia large, surstyli elongated, three to four times longer than broad and not forked, black; superior lobes elongate, no sickle-shaped; cerci elongate and yellow, "chitinous box" (= apex of hypandrium= superior lobes) elongated; lingula absent; aedeagus simple, no segmented, without apicomedial teeth.

Redescription

(modified from Fluke 1945: 22, and Mengual 2014). Body size. Large-sized flies, 9-12 mm. MALE. Head (Fig. 13A-C, E ). Face large, shining black, wider than the thorax and abdomen, straight to perpendicular, not produced, with a large well-rounded tubercle (low dorsally, not distinct in some Argentinomyia ), densely pollinose, sides of face usually with coppery reflections and a faint, slightly rugose area; front not swollen; gena large; oral tips, ocellar triangle, and the large triangular macula on the front shining black; pile on front generally black, on gena and face yellow to white, on ocellar triangle black, on the occiput yellow except the dorsal pile black; eyes bare, holoptic in male, with eyes contiguity as long as ocellar triangle; antennae black, pedicel and the lower basal corner of basoflagellomere red, short, scape broader than long, nearly equal to pedicel, basoflagelomere large, rounded or oval, ratio 1.1:1.5:2.5, arista black, dorsobasal, as long as the basoflagellomere or more, bare. Thorax (Fig. 13A-F ): Black; postpronotum (humerus) bare; notopleuron with distinctive tubercle; scutum shining, covered with yellow pollen and short golden pile with many longer black pile that appear yellowish at the base, these pile become longer posteriorly; pleura yellow pollinose and pilose; scutellum black and with transversal rugose area on the disc, generally with longer yellowish and black setae on the posterior margin; subscutellar fringe complete, with multiple rows yellow pile; postmetacoxal bridge incomplete; pleura black to orange, whitish pollinose and pilose. Legs (Fig. 13C ). Black; profemora yellow on the apical 1/3, mesofemora yellow on the apical 1/3, metafemora yellow on the apical 1/3; all the tibiae yellow with a dark ring near the middle, more prominent on the metatibia; tarsi brown, the pile yellow, black on the metatibia and above on the tarsi. Wing (Fig. 13A-F ). Smoky; membrane entirely microtrichose, except for extensive bare areas on basal half (cells c, sc, r1, dm, and bm); the stigma and costal cell brownish; vein R4+5 straight; vein M1 (apical crossvein) oblique, slightly sinuous; alula broad, broader than cell cup, extensively bare,; calypter yellow, plumule simple, yellow; halter yellow, with a darkened capitulum. Abdomen (Fig. 13B-F ). Elongated, black, with parallel sides, as broad as or broader than thorax, segments more or less quadrate, as long as broad, without premarginal sulcus, markings on tergites variable, with four pairs of lateral rounded to triangular prominent yellow maculae or with a complete basomedial black maculae; the first tergum shining, second with broad lateral yellow and only the apex black, third tergum with similar but wider maculae, fourth tergum with still wider but less elongate maculae, fifth tergum with a pair of small maculae in the basal corners. Pile yellow on the sides basally, black down the middle and on the apical terga. Male genitalia as Figs 12E , 14 .

Female. (Fig. 13C-E ). Similar to male except for normal sexual dimorphism. Abdominal maculae are comparatively shorter than in the male. Front narrow above, not the much wider than the ocellar triangle, shining above with a pollinose transversal macula below. Sixth tergum with a pair of small basolateral maculae. Sterna extensively yellow, yellow pilose, only brownish pilose in the apical corners of sterna four to sixth.

Distribution.

Talahua fervida is exclusively restricted to the Tropical Andes of Central and Occidental Cordillera in Colombia (Antioquia, Boyacá, Cundinamarca, Tolima) to Central Cordillera in Ecuador ( Bolívar, Sucumbios). The species has a mountainous distribution in the biogeographical provinces of Cauca, Magdalena and North Andean Páramo (Fig. 17 ).

Additional material examined.

COLOMBIA: Antioquia, Bello, San Félix, Las Baldías, 6°20.029'N, 75°39.263'E, 2950-3150 m a.s.l., Net, 22.ii.2015; A. L. Montoya Leg. (1 ♀, CEUA 92108); Belmira, Páramo Santa Inés, Cabaña Cabildo Verde, El Morro-Alto de La Gallina, 6°40.167'N, 75°40.136'E, 3247 m a.s.l., Net in Clusia cf. brachycarpa Cuatrec., 4-14.ii.2017, A. L. Montoya; J. Sanchez; E. Orozco-G Leg. (1 ♂, CEUA 95345); Medellín, Corregimiento San Sebastián de Palmitas, Vereda La Volcana, High part, 6°21.232'N, 75°40.883'E, 2569-2650 m a.s.l., Van Sommeren-Rydon trap baited with fish, 22.ix.2011, L. Ríos-M Leg (1 ♀, CEUA 93328); San José de la Montaña, Vereda El Congo, Sector La Laguna, 6°46.013'N, 75°41.979'E, 3100-3183 m a.s.l., Net, 21-30.vi.2017, C. Henao; A. F. Sepúlveda Leg (1 ♀, CEUA 98074); Sonsón, San Francisco, Las Palomas A Mountain hill, 5°43.924'N, 75°15.444'E, 2749 m a.s.l., Forest, Net, 1-12.ix.2018, A.M. Echeverry, J. Vallejo Leg. (1 ♀, CEUA 103636); Boyacá, Flora and Fauna Sanctuary Iguaque, Ravien Carrizal, Cabaña Mamarramos, Lagunillas, 5°41.783'N, 73°26.516'E, 2850-3380 m a.s.l. (IAvH, in Gutiérrez et al. 2006). ECUADOR: Sucumbios, Santa Barbara, 0°37.868'N, 77°31.207'E, 3023 m a.s.l., 14.iii.1994, Gonorre Leg (1 ♂, QCAZ 103712).

Ecology.

Adults of Talahua fervida are found in highland ecosystems including cloud forests of the Andesand Páramo from 1800 to 3350 m a.s.l. The species has been associated with flowers of Clusia cf. brachycarpa Cuatrec ( Clusiaceae Lindl.), but the immature stages are unknown.

Figures

Figure 12. Genus Talahua Fluke: A head, frontal, male B basoflagellomere, frontal view C metacoxa pile tuft, ventral view D scutellum emarginated, dorsal view E male genitalia, lateral view F holotype, AMNH G paratype label, USNM. Scale bars: 5 mm.

Figure 13. Talahua fervida, male (CEUA 95345): A dorsal view, male B lateral view (Paratype USNM). Female (CEUA 93328): C lateral view D dorsal view E posterior view, detail of maculae on sixth tergum. Scale bars: 5 mm.

Figure 14. Talahua fervida, male genitalia: A whole genitalia including epandrium, cercus and surstylus, lateral view B hypandrium, dorsal view C cerci, and surstyli, ventral view D cerci and surstyli, dorsal view. Scale bar: 0.05 mm.

Figure 17. Biogeographical distribution of Talahua fervida (light blue).