Syneches ruficollis ( Walker, 1852 )

Soares, Matheus M. M., Freitas-Silva, Rafael A. P. & Ale-Rocha, Rosaly, 2021, Review of Brazilian species of Syneches Walker (Diptera, Hybotidae, Hybotinae), with description of ten new species, Zootaxa 5049 (1), pp. 1-84 : 60

Syneches ruficollis ( Walker, 1852) nomen dubium

Hybos ruficollis Walker, 1852: 206 .

Syneches ruficollis: Bezzi, 1909: 314 (key); Collin, 1933: 28 (cit.); Smith, 1962: 212 (cit.); 1967: 9 (cat.); Yang et al., 2007: 307 (cat.). Type locality: Brazil.

“ Niger, thorace luteo, antennis flavis, pedibus fulvis, alis limpidis apice subfuscis.”

“ Head black: eyes red; facets very large: sucker tawny: feelers yellow: chest luteous: abdomen black, shining, thinly clothed with hoary hairs: legs tawny, clothed with pale yellow hairs: feet dark tawny: wings nearly colourless, pale brown at the tips; a spindle-shaped dark brown spot near the tip of the fore border; wing-ribs tawny; veins black, tawny at the base; poisers tawny” ( Walker 1852).

“Length of the body 1 ½ line; of the wings 4 lines.”

“Type-locality: Brazil.”

Remarks. Syneches ruficollis was described based on a single female from Brazil. Smith (1962) reported that the holotype could not be found in the Natural History Museum (NHMUK) and that it was possibly lost. According to the original description, the species has the following set of relevant characters: antenna yellow, thorax brownish yellow, legs yellow covered with concolorous bristles, all tarsus or some of them dark brown, abdomen black and wing hyaline with pterostigma spindle-shaped (= oval). Some of these characters are common in many Brazilian species: S. fasciatus sp. nov. and S. flaviscutellatus sp. nov. (antenna and legs mostly yellow, but both species have a distinct color pattern on the thorax and the wing mostly brown), S. sinclairi sp. nov. (but the female has an inconspicuous pterostigma and all the tarsi yellow) and S. tenebricus (but all tarsi are yellow and the wing is brownish). Thus, without analyzing the holotype, it is impossible to correctly associate S. ruficollis with any Brazilian species, hence we treat this name as a nomen dubium.