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.
Salpingogaster nigra has face yellow with medial black vitta, wing bicolour (anterior margin dark) extensively bare basally, alula broader than costal cell, and pleuron and abdomen mainly black with yellow markings.
New description:
MALE.
Head: Face with facial tubercle, oral margin close to the tubercle, yellow with medial broad dark vitta, yellow pilose; gena brownish; lunule yellow, black medially; frontal triangle black medially with yellow fascia on posterior margin and yellow macula dorsad to each antennal base, black pilose; dichoptic, eye bare; vertical triangle narrow, black, black pilose, with ocelli close to anterior margin; antenna orangish, black pilose, basoflagellomere darker dorsally; antennae on protuberance, distinct in profile; occiput black, silver pollinose, yellow pilose.
Thorax: Scutum black to dark brown with two dorsomedial broad white pollinose vittae, yellow pilose laterally and mostly short black pilose; postpronotum yellow, bare; notopleuron black on anterior half, yellow on posterior half, yellow pilose; scutellum dark brown to black, with anterior and apical margin yellow, short black pilose, subscutellar fringe absent. Pleuron mostly black, except posterior anepisternum yellow on posterior half, and katepisternum with large dorsal yellow macula; metasternum bare; postmetacoxal bridge complete; calypter brownish; plumula absent; halter brownish; spiracular fringes yellowish. Wing: Wing membrane hyaline, with anterior margin and basal area (before vein h) dark brown; vein M1 strongly sinuated and vein R4+5 strongly sinuated into cell dark brown R4+5; extensively bare medially, only microtrichose apically and anteriorly. Alula bare, as broad as cell BM. Legs: Femora with ventral spinose bristles; entirely black to dark brown except pro- and mesotibiae yellow on basal half and metatibia yellow on basal 1/3.
Abdomen: Strongly and distinct petiolate, with tergum 2 cylindrical and narrower than thorax, tergum 3 broadening gradually posteriorly, unmargined. Tergum 1 produced laterally into a strong spur, yellow on anterior half, black on posterior half; tergum 2 entirely brown to black; tergum 3 black, brownish basally with two subbasal yellow maculae on lateral margins; terga 4 to 8 black or dark brown; sterna dark brown to black except sternum 1 yellow and sternum 3 with subbasal yellow fascia; sternum 4 with medial depression on posterior margin, which is produced laterally into two projections; male genitalia large.
FEMALE.
Similar to male except frons black with yellow macula dorsad to each antennal base and lateral yellow vitta on eye margin medially; tergum 3 black, brownish basally with two subbasal yellow maculae on lateral margins, and with medial very narrow yellow fascia on posterior margin. Abdomen in females more flat without modifications in sternum 4.
The group was first recognized and named by Walker (1852: 223). Unfortunately his description was brief and his name, Amathia, was preoccupied. Walker did note the two critical characters for the group, the sinuate vein R4+5 and spines on the femora. Schiner (1868: 344) subsequently re-described the genus and provided the name, Salpingogaster.
Synonym:
Salpingogaster anchoratus Bigot, 1884: 328.
Salpingogaster nigra Schiner, 1868.
Schiner, I.R. (1868) Diptera. vi + 388 pp., 4 pls. In [Wullerstorf-Urbair, B. von (in charge)], Reise der osterreichischen Fregatte Novara. Zool. 2(1)B. K. Gerold's Sohn, Wien. [1868.04.30]
Mengual et al. (2008) included several Salpingogaster species in their molecular phylogeny. The genus was recovered as monophyletic in two different positions using different weighting schemes: as a sister group of Asarkina, Meliscaeva, Episyrphus, Allograpta, Sphaerophoria and Exallandra (1:1, gap:indel); or as a sister group of Allograpta, Sphaerophoria and Exallandra (2:1, gap:indel).
unless otherwise stated