Ocyptamus (Mimocalla) tristani Zumbado, 2000.
Thompson, F.C. & Zumbado, M. (2000) Flower flies of the subgenus Ocyptamus (Mimocalla Hull) (Diptera: Syrphidae). Proceedings of the Entomological Society of Washington 102, 773-793. [2000.10.17]
Thompson and Zumbado (2000) described tristani. Before, Hull (1943) described the subgenus Baccha (Mimocalla) for those species with a stronly petiolate, clubbed abdomen and greatly enlarged hypopygium, but also with a looped vein R4+5 and sigmoid M1.
This species has been reared a number of times, and specimens have been submitted for identification to the Systematic Entomology Laboratory, USDA. The determination labels associated with the specimens in the USNM indicate that the species was first incorrectly identified as Baccha bromleyi by Hull and this mistake was perpetuated by subsequent specialists (e.g., W.W. Wirth, L.V. Knutson) as either bromleyi or new species near bromleyi. Apparently none of these misidentifications were published (Thompson and Zumbado 2000).
From Thompson and Zumbado (2000).
MALE.
Head: Face yellow, with light orange medial vitta, sparsely white pollinose laterally, only densely pollinose narrowly along eye margin, white pilose except black pilose ventrad to antenna; gena yellow, shiny, bare; lunule yellow except brown medially; frontal triangle yellow except brown along lunule, black pilose; vertical triangle black, black pilose; occiput black except yellow on ventral 1/5, densely yellowish-white pollinoseventrally becoming more golden dorsally, white pilose ventrally becoming more golden dorsally; antenna brown except more brownish orange basoventrally on basoflagellomere and yellow on inner side of scape and pedicel, black pilose; basoflagellomere elongate, slightly less than twice as long as wide.
Thorax: Mainly yellow with black maculae; prothorax yellow; scutum black except with broad yellow vitta running from postpronotum to and including anterior 1/2 of postalar callus but narrowly attenuated dorsad to wing base, with vitta about as wide as postpronotum, with black areas black pollinose except for broad golden pollinose submedial vitta which tapers posteriorly and does not reach scutellum and a very narrow indistinct brown pollinose medial vitta on anterior 2/3 which expands into a broader golden pollinose vitta at level of postalar callus, long yellow pilose anteriorly and laterally, short intermixed black and yellow pile elsewhere; scutellum yellow except disc blackish, short sparse black pilose with a few intermixed yellow pili basally; subscutellar fringe singular, white; pleuron yellow except black narrowly on anterior convex surface of posterior anepistemum, ventral 2/3 of katepistemum, posteriorly on katatergum and anteriorly on anatergurn, very sparsely white pollinose except denser dorsally on katepistemum, yellow pilose; plumula absent short, yellow; calypter yellowish white except dorsal margin brownish; halter yellow, with capitulum brownish. Legs: Proleg yellow except slightly brownish subapically on posterior of femur, sparsely gray pollinose, yellow pilose; mesoleg yellow except sligthly brownish on base of and subapically on posterior of femur, yellow pilose except for a row of black pili on dorsoposterior surface; metacoxa brown, long black pilose with intermixed yellow pili laterally; metatrochanter brown, long black pilose; metafemur yellow except black ventrally and posteriorly except apically, black pilose except yellow pilose on yellow area; metatibia yellow except brownish medial lh, yellow pilose; metatarsus yellow except brownish-orange basotarsomere, yellow pilose. Wing: Hyaline except stigma brownish and cell Sc yellowish orange, microtrichose except bare cell R posterior to spurious vein on apical 1/3, cell BM, anterobasal 1/3 of cell CuP, cell R4+5 posterior to spurious vein, narrowly on basoposteriorly in cell DM, basomedial 1/3 of cell CuA1, anterior to vein A2; alula microtrichose, normal, as wide as cell CuP.
Abdomen: Dark brown with broad yellow fasciae; 1st tergum yellow on basal 2/3, black apically, yellow pilose basally, black pilose apically; 2nd tergum brownish black except for large yellow basolateral triangular macula and medial inverted V-shaped macula, with basolateral maculae narrowly separated medially and occupying basal 1/2 of tergal length, with V-shaped macula slightly beyond middle of tergum and completely surrounded by black areas, yellow pilose basolaterally, black pilose elsewhere; 3rd tergum yellow on basal 3/8, brownish black apically, yellow pilose on yellow area, black pilose elsewhere; 4th tergum yellow on basal 1/3, margin and apicolateral corner, elsewhere black, yellow pilose; 5th tergum yellow except with broad medial black fasciate macula, black pilose; genitalia yellow, black pilose; 1st sternum yellow, yellow pilose; 2nd sternum brown except yellow basally, yellow pilose; 3rd sternum brown except yellow basal 1/3, black pilose except yellow pilose basally; 4th sternum brown, brown pilose; 5th sternum orange except yellow apically, brown pilose.
FEMALE.
Similar to male except for normal sexual dimorphism and frons black except yellow broadly along eye margin, short black pilose.
unless otherwise stated