Mesoconius nigra, Marshall, 2019

Marshall, Stephen A., 2019, A revision of the genus Mesoconius Enderlein (Diptera, Micropezidae, Taeniapterinae), European Journal of Taxonomy 548, pp. 1-126 : 109-111

Mesoconius nigra sp. nov.

urn:lsid:zoobank.org:act:B032E41E-1F0A-490A-9907-10E7B8847C50

Fig. 44

Etymology

Mesoconius nigra is named for its almost entirely black body and darkly pigmented wings.

Material examined

Holotype BOLIVIA • ♀; La Paz, Coroico, Cerro Uchumachi ; 16°12ʹ43ʺ S, 67°42ʹ49ʺ W; 2550 m a.s.l.; 5 Apr. 2001; S.A. Marshall leg.; cloud forest; CBFC.

Paratypes

BOLIVIA • 2 ♀♀; same collecting data as for holotype; MYCRO070-15 sequenced for CO1; DEBU .

Description (females only)

LENGTH. 16–17 mm.

COLOUR. Mostly brown to black, fore tarsus white, hind tarsus white basally and darkened distally, palpus pale orange. Frontal vitta velvety black. Hind femur with a broad white band just beyond middle; mid femur with a narrow band. Wing uniformly black. Abdominal pleuron dark.

HEAD. Epicephalon and paracephalon smooth and shiny. Frontal vitta narrow, only slightly raised, narrow and indistinct behind ocelli, where it expands to a microtrichose patch between postocellar bristles; anteriorly tapered to near anterior margin of frons. Postocellar bristles and inner vertical bristles well developed. Upper fronto-orbital absent, lower fronto-orbital large, inserted at point of overlap between orbital plate and epicephalon.

THORAX. Scutum inconspicuously microtrichose; dorsocentral and acrostichal setulae very small. Cervical sclerite oblong, with a small, depressed anterior portion divided by a vertical carina; posterior portion elevated, but with surface bare and flat-topped or slightly depressed at middle. Prosternum microtrichose and strongly setose. Postpronotal lobe sparsely microtrichose and very sparsely setulose, anterior surface vertical and shiny along dorsal margin, posterior surface sloped and microtrichose, except for ventral carina. Dorsocentral bristle slightly longer than scutellum. Scutellum with minute discal setulae and one pair of long apical bristles (longer than scutellum). Vertical row of katepisternal bristles golden. Katatergite not swollen, without median process, evenly convex and microtrichose. All coxae with an anteroventral tuft of long black setae.

ABDOMEN. Abdominal segment 1 petiolate on basal half only, T2 short and expanded posteriorly. T3–5 narrow and depressed relative to T2 and T6. Pleuron greatly expanded on segments 3–5. Bursa small, subquadrate, with a small distal ventral receptacle, spermathecal ducts arising separately from apex of bursa. Both ducts lead to pairs of spermathecae, with one duct and one pair of spermathecae slightly larger than the other duct and spermathecae. The smaller spermathecae are narrow and long, on short stems, the larger spermathecae are short and on longer, convoluted stems.

Remarks

Mesoconius nigra sp. nov. is similar to, and obviously closely related to, M. quadritheca sp. nov. from Peru. These species share the four spermathecae, limited constriction at the abdominal base, narrowed T3–5, and similar colour and general habitus, but M. nigra sp. nov. differs from M. quadritheca sp. nov. in having well-developed vertical and postocellar bristles. Mesoconius ruficrus sp. nov. from Peru is also very similar, but differs in colour. All three species share a setose prosternum.

Figures

Fig. 44. Mesoconius nigra sp. nov. A. Head, dorsolateral view. B. Holotype, ♀, CBFC. C. Posterior part of thorax, lateral view. D. Spermathecae and associated structures. E. Living ♀.