Eosalpingogaster and Salpingogaster are readily distinguished from all other syrphine groups by the presence of distinct black spinose bristles on the metafemur combined with the petiolate abdomen and sinuate vein R4+5. Both genera have petiolate abdomens, but Salpingogaster is distinguished from Eosalpingogaster by the much more greatly sinuate vein R4+5; other syrphines with sinuate vein R4+5 have oval abdomens. Eosalpingogaster has 1st tergum not produced into a spur, vein R4+5 only slightly sinuate and occipital cilia in 3–4 rows dorsally. In contrast, Salpingogaster has 1st tergum produced laterally into a strong spur and occipital cilia reduced to a single row dorsally.
Very similar to E. cochenillivora, but E. nigriventris has 4th tergum with two basolateral triangular yellow maculae, scutum with a medial broad pollinose vitta, and femora with yellow apical area broader. Eosalpingogaster nigriventris has a larger geographical distribution than E. conopida, with records from the Andean region only.
Eosalpingogaster has been considered as a subgenus of Salpingogaster since Hull (1949b) proposed it for Baccha conopida Philippi, including nepenthe Hull and dactylopianus Blanchard. In the original text, Hull wrote "Corners of first abdominal segment with a sharp hook" but one of the differences with Salpingogaster s.str. is that Eosalpingogaster has 1st tergum not produced into a spur. There are evidences to consider Eosalpingogaster a different and valid genus.
Synonyms:
Salpingogaster nigriventris Bigot, 1883: 329.
Salpindogaster nigriventris [missp.]: Lynch Arribalzaga, 1892: 248.
Baccha mimetica Brèthres, 1907: 292 [nomen nudum, attributed to Lahille].
Salpingogaster liposeta Fluke, 1937: 10.
Salpingogaster dactylopianus Blanchard, 1938: 348.
Eosalpingogaster nigriventris (Bigot, 1884).
Bigot, J.M.F. (1884) Dipteres nouveaux ou peu connus. 22e partie, XXXII: Syrphidi (2e partie). Especes nouvelles, No 1er. Annales de la Société entomologique de France (6) 3, 315-356. [1884.01.31]
Very similar to E. cochenillivora, but differs by having the scutum only reddish laterally, black anterior to scutellum; 4th tergum with a pair of yellow basolateral triangular maculae; scutum with medial broad white pollinose vitta, usually broader than ocellar triangle; femora yellow on apical 1/6–1/5.
Length (5): body, 12.1–12.7 (12.4) mm; wing, 8.7–9.4 (9.1) mm.
Eosalpingogaster conopida was the only species included in the molecular phylogeny by Mengual et al. (2008a). In their analysis, Eosalpingogaster was resolved as sister group of Ocyptamus melanorrhinus, embedded in a clade formed by Ocyptamus and Toxomerus species. This placement was recovered again in Mengual et al. (2008b) when they used them as outgroup for Allograpta.
Eosalpingogaster was proposed by Hull (1949: 299) as a new subgenus of Salpingogaster Schiner. Hull based his decision on the absence of a sharp hook on anterior corners of the first abdominal segment and on the slight curvature of vein R4+5. In contrast, the species of the genus Salpingogaster have the first abdominal tergum produced laterally into a strong spur and vein R4+5 strongly sinuate.
Eosalpingogaster larvae are predators of scale insects (Coccoidea), in contrast with the larvae of Salpingogaster, which feed on spittlebugs (family Cercopidae).
The results from the molecular analysis by Mengual (Mengual and Thompson 2011) resolved Eosalpingogaster and Salpingogaster in two different clades, independent of the method used to infer the phylogeny, and they considered Eosalpingogaster as a valid genus.
A similar result was obtained by Mengual et al. (2012).
E. nigriventris is the speceis with the broadest distribution in the genus; it is known from Argentina, Uruguay, Peru, Ecuador, Venezuela, Trinidad and Brazil.
unless otherwise stated