Mesoconius rufithorax Enderlein, 1922

Marshall, Stephen A., 2019, A revision of the genus Mesoconius Enderlein (Diptera, Micropezidae, Taeniapterinae), European Journal of Taxonomy 548, pp. 1-126 : 47-48

Mesoconius rufithorax Enderlein, 1922

Fig. 17

Mesoconius rufithorax Enderlein, 1922: 178 .

Material examined

Lectotype (here designated, Fig. 17 A–B)

PERU • ♀; Cusco, Callanga, Piñipiñi Valley ; 1500 m a.s.l.; O. Garlepp leg.; MNBG .

Paralectotypes

PERU • 2 ♀♀; same collecting data as for holotype; MNBG .

Enderlein also lists a specimen from Songo, Bolivia in HMNH (not examined).

Other material

BOLIVIA • 4 ♀♀; Coroico; 1200 m a.s.l.; “ Coll. Fasel ”; BMNH .

Redescription (females only)

LENGTH. 17–18 mm.

COLOUR. Head mostly black or almost black anterior to ocelli, orange behind ocelli, clypeus, membranous lower face and palpus yellow; parafacial, gena part of postocciput silver–microtrichose. Cervical sclerite entirely orange and subshining. Thorax and syntergites 1–2 orange, femora orange and almost bare basally, black and microtrichose distally, fore and hind tarsi white, except for a black ventrobasal part of fore tarsomere 1. Wing mostly uniformly lightly infuscated, with an indistinct preapical clear area. Abdomen black distally, abdominal pleuron mostly pale, but at least in females with prominent black vertical bands on P2–4, tapered ventrally from tergites, P5 mostly black.

HEAD. Epicephalon and paracephalon shiny, very finely striate; frontal vitta depressed, sharply tapered posterior to ocelli, broad and diffuse anterior to ocelli, with an inconspicuous anteromedial point, widely separated from anterior margin of frons. Inner vertical bristle strong, with four–five setulae near base. One weak fronto-orbital bristle inserted below level of anterior ocellus. Upper face broadly raised. Clypeus bare anteriorly, setulose laterally.

THORAX. Cervical sclerite with a vertical groove separating a large, subquadrate microtrichose posterior portion from a small, bare anterior portion. Notum finely and densely microtrichose, acrostichal and dorsocentral setulae in indistinct rows, scattered setulae also present anterolaterally. Postpronotal lobe sparsely microtrichose, with several scattered small pale setae; posterior half with a central longitudinal ridge, anterior half rounded. Dorsocentral bristle longer than length of scutellum. Scutellum with four small discal setulae and long, closely spaced black apical bristles (longer than scutellum). Katatergite prominent but rounded, without a nipple-like apex. Notopleuron with two widely spaced black bristles. Vertical row of katepisternal bristles golden. All coxae with golden anteroventral setae.

ABDOMEN. Abdominal segment 1 and base of segment 2 petiolate; length of 1+2 slightly more than double that of tergite 3. T1 setose, with preapical long, thin lateral setae.

FEMALE ABDOMEN (based on BMNH non-type specimens). Oviscape bare except for scattered setulae. Bursa small, suboval, finely wrinkled; ventral receptacle small and inconspicuous, like a small, distally bent finger. Single and paired spermathecal ducts similar in width, length and texture, both arising from a broad extension of the bursa. Single spermatheca cylindrical, distinguishable from duct only by its heavier sclerotization; paired duct uniformly smooth, slightly expanded distally before branching into short, slightly convoluted ducts leading to almost spherical, striate spermathecae.

Remarks

The combination of an anteriorly darkened head, distally black femora and three bold pleural black stripes distinguish this species from the many other mostly orange species of Mesoconius .

Figures

Fig. 17. Mesoconius rufithorax Enderlein, 1922. A–B. Lectotype, ♀, MNBG, Peru. C. ♀, Bolivia. D. Spermathecae and associated structures, lateral view, Bolivia.