Mesoconius zadbi, Marshall, S. A., 2015

Marshall, S. A., 2015, Mesoconius Enderlein (Diptera, Micropezidae, Taeniapterinae) of Central America, Zootaxa 3914 (5), pp. 525-540 : 539-540

Mesoconius zadbi new species

Figs. 6A–6D

Description (females only): Length (antenna to wing tip) 15 mm. Color: Black to dark brown except as follows: gena, extreme anteroventral corner of face and parafacial silvery pruinose, palpus orange–yellow, margin of frontal vitta silvery pruinose. Face and antenna reddish brown. Fore tarsus white with white setae, hind tarsus white with white setae on tarsomeres 1–2, mixed white and brown setae on tarsomere 3, brown setae on tarsomeres 4–5; fore femur narrowly orange basally, black distally; mid and hind femora black with orange apex. Fore tibia black, mid tibia and hind tibia orange to yellow. Distal abdominal scerites reddish.

Head: Epicephalon and paracephalon with a microscopic pattern of longitudinal striations, shining, smooth, sharply contrasting with orbits and lower frons; frontal vitta velvety black, sharply constricted behind ocelli, then expanded to a densely microtrichose area between postocellar bristles; widely separate from anterior margin of frons. Outer vertical bristles absent, inner vertical bristles strong, postocellar bristles strong. Fronto-orbital bristles (2) strong and widely separated. Upper face entirely microsetulose, strongly and broadly carinate; parafacials, gena, and outer corner of face strongly silvery pruinose, subantennal areas shining reddish brown. Palpus yellowish.

Thorax: Cervical sclerite with a vertical groove separating a microtrichose, subquadrate posterior portion from a small bare anterior portion. Notum microtrichose, without acrostichal setulae but with a distinct row of small dorsocentral setulae; postpronotal lobe microtrichose with some scattered small setulae, anterior margin forming a vertical, shining face. Katatergite very prominent, with a tapered microtrichose apex. Vertical row of katepisternal bristles yellow. Coxae with anteroventral golden bristles.

Abdomen: Syntergite 1+2 very narrow basally, constriction between syntergites about half as wide as base of T3; length of T1+2 double length of T3.

Female abdomen: Pleuron dark on dorsal half of segments 2–5, otherwise pale. Oviscape reddish brown, paler apically. Bursa copulatrix large, ventral receptacle small. Single spermatheca small, slightly broader than duct; paired spermathecal duct similar in diameter to paired duct but longer and divided into a broad striate distal half and a narrower smooth distal half, distally dividing into long spermathecal bases each with a subbasal elongate oval swelling and a distal sinuate section with 2–3 deep S–bends. Paired spermathecae elongate, distinctly striate, tapered basally.

Type material (all INBC): Holotype (♀): COSTA RICA. Cartago, Rio Macho forest reserve, La Esperanza del Guarco, end of Esperanza road, 2400 m. 1–2.vi.1998, S.A. Marshall. Paratypes: COSTA RICA. Cartago, Paraíso, PN Tapantí, Macizo de la Muerte, 1500 m. 19.v.2000, malaise, C. Hanson, D. Rubi (1 ♀). San José, Moravia, Zurquí de Moravia, tower path, 1600 m. 24–31.v.2013, Malaise, project ZADBI (1 ♀).

Etymology. The specific name refers to Project ZADBI , the Zurquí All Diptera Biodiversity Inventory. Mesoconius zadbi and most of the other Mesoconius species newly described here are described partly on the basis of specimens from Project ZADBI .

Comments. Although this species remains known only from males, M. zadbi clearly belongs in Mesoconius and can be placed in a clade characterized by a paired spermathecal duct with a striate basal half and a smooth distal half.

This species is similar to the South American Mesoconius infestus group, but differs most obviously by its black mid and hind femora with contrasting orange apices. M. zadbi is probably most closely related to M. bicolor , but characters of the as yet unknown males are needed to test that hypothesis.

Figures

FIGURE 6 A – D. Mesoconius zadbi. A, head; B, female; C, thorax – abdomen junction to show pointed katatergite; D, spermatheca and associated structures.