Xanthandrus (Androsyrphus) setifemoratus Thompson, 1981.
Thompson, F.C. (1981) The flower flies of the West Indies (Diptera: Syrphidae). Memoirs of the Entomological Society of Washington 9, 200 pp. [1981.09.02]
Adapted from original description (Thompson 1981).
MALE.
Head: Black; face and gena silvery-white pollinose except shiny on tubercle, yellow pilose laterally; frontal lunule black; frontal triangle shiny except narrowly white pollinose laterally, yellow pilose; vertical triangle shiny, yellowish-brown pilose; ocellar triangle about twice its length anterior to posterior eye margin; occiput silvery-white pollinose, white pilose becoming slightly more yellowish above. Antenna: scape brownish orange, black pilose; pedicel yellow, black pilose; basoflagellomere yellow except apicodorsal 1/3 black, elongate oval, about 5/6 as long as broad; arista brown, as long as antenna.
Thorax: Black, with a slight bluish-green sheen, white pilose; scutum and scutellum shiny; pleuron sparsely white pollinose except more densely pollinose on posterior anepisternum and dorsal katepisternum; calypter and plumula pale orange; halter orange with capitulum slightly darker. Legs: Coxae dark, sparsely white pollinose, white pilose; trochanters dark reddish brown, yellow pilose; profemur reddish brown except orange apex, yellow pilose; mesofemur dark reddish brown and yellow pilose on basal 2/3, orange and black pilose on apical 1/3, with black ventral spinose setae on apical 1/2; metafemur dark reddish brown except orange apex, yellow pilose except black pilose on apical 1/4, with strong long black ventral spinose setae on apical 4/5; pro- and mesotibiae orange, with slightly brownish medial tinge, black pilose, with some longer and stronger black pile on posteromedial 1/3; metatibia dark reddish brown except orange on base, black pilose; protarsus dark brown, black pilose; mesotarsus orange on basal 2 tarsomeres, brownish on apical 3 tarsomeres, black pilose; metatarsus brownish black, black pilose. Wing: with brownish tinge, extensively microtrichose, bare as follows: 1st costal cell, basal 4/5 of 2nd costal cell; above Rs, cells R and BM, basal 1/5 of cell R4+5, posterobasal 1/4 of cell dm, along anterior and posterior edges of cell CuA1 on basal 1/2, anterobasal 1/2 of CuP, in front of A2, and basal 5/6 of alula; tegula and basicosta brownish-black pilose.
Abdomen: 1st tergum shiny black, yellow pilose; 2nd tergum mainly dull black, shiny laterally, with 2 large sublateral orange maculae which extend over lateral margin on their anterior 1/3, with maculae broadly separated, yellow pilose on margins and maculae, short black pilose elsewhere; 3rd tergum similar to 2nd but with maculae isolated from lateral margins; 4th tergum mainly dull orange, shiny laterally, with indistinct medial brown vitta and apicomedial triangle, yellow pilose laterally and on basal 1/2, black pilose elsewhere; 5th tergum dark reddish brown, yellow pilose; 1st sternum dark brown, sparsely white pollinose, white pilose; 2nd sternum dark orange, shiny, yellow pilose; 3rd sternum dark reddish brown, shiny, yellow pilose; 4th sternum orange, densely pilose, with lateral pile longer and medial pile long but slightly decumbent; genitalia black, black and brown pilose.
Thompson (1981) considered Androsyrphus to be the sister-group of Xanthandrus and he ranked it as a subgenus of Xanthandrus. In the tribe Melanostomatini (Fluke, 1958) many generic names have been based on special modification of the male legs, but most of these have now been reduced to subgenera or synonymized. Thompson (1981) also said that the spinose femora of setifemoratus will be found to be non-sexually dimorphic because this character is not sexually dimorphic in other syrphid genera, and decided to create a new subgenus for this species.
Androsyrphus has not been included in phylogenetic analyses. Mengual et al. (2008) included 2 species of Xanthandrus in their molecular analysis. Both were resolved together as sister group of the clade including Argentinomyia and Melanostoma.
Xanthandrus has been considered member of the tribe Bacchini sensu lato, although some phylogenetic analysis suggest that Baccha is the only memeber of Bacchini and the other genera commonly related to them should be included in the tribe Melanostomini. Rotheray and Gilbert (1989, 1999) included Melanostoma and Xanthandrus, which, in their analysis, were isolated from the other genera of the ‘‘traditional’’ Bacchini by the tribe Syrphini. These authors also suggested the tribe Melanostomini with only Melanostoma and Xanthandrus as Palaearctic members.
The original Holotype label has the name Xanthandrus spinifemoratus, instead of the correct name Xanthandrus setifemoratus.
unless otherwise stated