Mixogaster conopsoides Macquart, 1842.
Macquart, P.J.M. (1842) Dipteres exotiques nouveaux ou peu connus. Tome deuxieme. 2e partie. Mémoires de la Société Royale des Sciences, de l'Agriculture, et des Arts à Liège 1841(1), 65-200, 22 pls.
Mixogaster is a group of petiolate Microdon flies restricted to the New World. They are distinguished from all other petiolate Microdon groups by 1) lacking an appendix on vein R4+5; 2) having a reduced and bare metasternum; 3) unarmed scutellum; and 4) usually an appendix on vein M extending in cell R4+5. Some earlier authors more broadly interpreted the concept of this genus and described species now placed elsewhere [aphritina Thomson = Paramixogaster, bellula Williston = Pseudomicrodon, cinctella Sack = Paramicrodon, claripennis Hine = Pseudomicrodon, nigripennis Sack = Paramicrodon, variegata Sack = Paramixogaster, and vespiformis Brunetti = Paramixogaster] (Cheng and Thompson 2008). Hull (1954) provided a revision of the genus.
From original description (Macquart 1842) in French.
Niger. Abdominis incisuris flavis. Alarum limbo externo fuscano.
♀. Face jaune, à petits poils blanchâtres; une bande longitudinale noire, rétrécie inférieurement et n'atteignant pas l’épistome. Front noir; une bande transversale jaune au bord du sillon: une petite tache jaune, carrée, au vertex. Antennes noires. Thorax noir; une petite bande fauve, longitudinale, de chaque côté, et une bande dorsale fauve; écusson brun. Abdomen noir; deuxième segment à base brune et bord postérieur jaune, ainsi que les bords latéraux; troisième à bord postérieur jaune; un peu de jaune au bord postérieur du quatrième. Pieds fauves; cuisses un peu brunâtres; jambes à moitié postérieure brunâtre, du côté intérieur. Ailes un peu jaunâtres ; bord extérieur brunâtre , formé par le bord brun des premières nervures longitudinales; première cellule postérieure à deux petits appendices au bord postérieur et un à l’intérieur.
New description:
FEMALE.
Head: Face straight, without tubercle, yellow with medial brown vitta broadening medially, with long yellow pile; gena narrow, yellow; lunule dark brown; frons yellow with medial dark brown macula dorsad to antennal base, dark pilose; dichoptic, eye bare; vertical triangle yellow with black macula between ocelli, black pilose; antenna dark, basoflagellomere micropilose, as long as scape and more than 3 times longer than pedicel; occiput narrow, a bit broader dorsally, yellow pilose.
Thorax: Scutum dark brown with dorsomedial broad yellow vitta and lateral margins broadly yellow, mainly with appressed yellow pile with some black pile medially; scutellum small, rounded, yellow with medial brown macula, yellow pilose, subscutellar fringe absent; subscutellum large. Pleuron mostly yellow, with meron, katepimeron and anterior part of anepimeron, anterior anepisternum and posterior anepisternum brownish-orange; anterior anpisternum pilose; metasternum bare; calypter yellow; plumula absent; halter yellow; spiracular fringes brownish. Wing: Wing membrane yellowish; extensively microtrichose, except cell CuP bare with some microtrichia apically, anal lobe abre basally and cell R4+5 bare between vein spurious and CuA1; vein R4+5 withou appendix; vein M with small appendix into cell R4+5; vein M1 sigmoid. Alula broad, bare, microtrichose apically. Legs: Entirely brownish, yellowish pilose; metatibia with two media incisions or depressions.
Abdomen: Petiolate, minimum width of tergum 2 narrower than thorax, concave, only tergum 2 margined. Dorsum mainly dark brown, terga 2, 3 and 4 with yellow fascia on posterior margin; tergum 2 with two medial yellow maculae on lateral margins.
Adapted from Hull (1954).
This species clearly possesses a bright, complete, yellow, medial vitta down the mesonotal disc, with the sides broadly yellow; the lateral margins, including postpronotum and postalar callus, give the thorax its distinctive trivittate appearance.
Body lenght: 12.4 mm (Macquart 1842).
Neotropical species known from Colombia and Brazil.
