Mesoconius albipedis, Marshall, 2019

Marshall, Stephen A., 2019, A revision of the genus Mesoconius Enderlein (Diptera, Micropezidae, Taeniapterinae), European Journal of Taxonomy 548, pp. 1-126 : 57-59

Mesoconius albipedis sp. nov.

urn:lsid:zoobank.org:act:B83A4AC4-D7FC-4699-A4F8-52F40C7AFF80

Fig. 22 A–G

Etymology

The specific name is from the Latin for ‘white’ and ’foot’, referring to the mostly white tarsi of this species. The name is deliberately similar to that of the closely related M. albitarsus .

Material examined

Holotype

COLOMBIA • ♀; San Antonio ; 2000 m a.s.l.; 16 Feb. 1908; C.T. Trechmann bequest; B.M. 1965 5249; BMNH.

Paratypes

COLOMBIA • 1 ♂; Villa Elvira ; 1800 m a.s.l.; 4 Jul. 1908; BMNH • 1 ♂; Rio Tocola ; 1800 m a.s.l.; 17 May 1908; C.T. Trechmann bequest; B.M. 1965 5249; BMNH .

Description

LENGTH. 19 mm.

COLOUR. Black to reddish brown, except for silvery gena and parafacial, yellow palpus, mostly white to yellow fore tarsomeres (tarsomere 1 white dorsally and dark ventrally, tarsomere 2 white, tarsomeres 3–4 yellow, tarsomere 5 dark), white hind tarsomeres 1–4, reddish mid and hind coxa, along with the adjacent femoral bases, and orange-red ventral parts of the metapleuron. Frontal vitta velvety black. Wing strongly infuscated at least anterodistally, with large but diffuse clear areas in cell r 2+3 and cell r 4+5. Oviscape dark brown to black, with some orange at apex.

HEAD. Epicephalon and paracephalon finely striate, subshining, slightly shinier than orbits; frontal vitta posteriorly sharply tapered to a very narrow microtrichose groove, ending before level of inner vertical bristles; broadly rounded in front of ocelli, half of frontal width, widely separated from anterior margin of frons. Upper face broadly raised, with a narrow and prominent carina at middle.

THORAX. Cervical sclerite with a vertical groove separating a posteriorly microtrichose, dark, subquadrate posterior portion from a small, bare, pale anterior portion. Notum with a broad silvery microtrichose longitudinal vitta on each side, postsutural part of silver vitta broad, with a central dark vitta. Postpronotal lobe shiny, very sparsely microtrichose, with some scattered small pale setae, anterior margin gently sloped, posterior apex longitudinally carinate.

ABDOMEN. Abdominal segment 1 and at least basal half of segment 2 petiolate (all of segment 2 petiolate in male); length of 1+2 slightly more than double that of tergite 3.

FEMALE ABDOMEN. Oviscape with basal ⅔ setulose, but less microtrichose than other tergites, distally shiny. Bursa with deep transverse striae, taperered to a short common duct branching into short, single duct and a long, paired duct divided into distinct parts, including a long rugose basal part that abruptly transforms into a slightly narrower, relatively smooth (indistinctly striate) distal part. Paired spermathecae expanded distally, surface with transverse striae, each spermatheca on a separate narrow stem, with a large ovate swelling just beyond basal quarter. Single spermatheca slightly enlarged, on a long stem separated from main part of duct by a constriction.

MALE ABDOMEN. Sternites 5 and 6 lightly sclerotized, small; S7 dark, with a broad anterior apodeme and an expanded, bare, spatulate right apex; S7 and S8 bare and shiny, contrasting with dull, microtrichose T1– 6; S8 1.5× length of epandrium. Epandrium small, microtrichose, with prominent, setose posteroventral angles, cercus large and distinct. Basal part of distiphallus broadly tubular, narrow basally but distally expanding to a large phallic bulb forming a distinctive broad hood over base of distal part of distiphallus. Ejaculatory apodeme narrow and elongate, slightly longer than epandrium.

Remarks

Mesoconius albipedis sp. nov. resembles the Peruvian species M. albimanus , known only from two females collected in the infamous Piñipiñi Valley. Mesoconius albimanus differs in having an orange to red katepisternum and tergite one, and in having an entirely black fore femur.

Figures

Fig. 22. A–G. Mesoconius albipedis sp. nov. A. Paratype, ♂, BMNH. B. Male terminalia, including segments 6–8. C. Male terminalia, excluding segments 6–8. D. Spermatheca and associated structures. E. Head and thorax, dorsolateral view. F. Holotype, ♀, BMNH, dorsolateral view. G. Holotype, ♀, lateral view. — H. Mesoconius albimanus Enderlein, 1992, lectotype, ♀, MNBG. Abbreviation: kt = katatergite.