Lachnocorynus stenocephalus, Boschert & Dikow, 2022

Boschert, Claire & Dikow, Torsten, 2022, Taxonomic revision of the mydas-fly genera Eremohaplomydas Bequaert, 1959, Haplomydas Bezzi, 1924, and Lachnocorynus Hesse, 1969 (Insecta, Diptera, Mydidae), African Invertebrates 63 (1), pp. 19-75 : 19

publication ID	https://dx.doi.org/10.3897/afrinvertebr.63.76309
publication LSID	lsid:zoobank.org:pub:F849C700-225A-4923-AE19-62882F933E83
DOI	https://doi.org/10.5281/zenodo.7577336
persistent identifier	https://treatment.plazi.org/id/42B6D785-DD4A-4B33-951F-D18E986D00C4
taxon LSID	lsid:zoobank.org:act:42B6D785-DD4A-4B33-951F-D18E986D00C4
treatment provided by	African Invertebrates by Pensoft
scientific name	Lachnocorynus stenocephalus
status	sp. nov.

Treatment

Lachnocorynus stenocephalus sp. nov.

Figs 50-52 View Figures 50–52 , 56 View Figure 56

Diagnosis.

The species is distinguished from congeners by the very narrow face (vertex much wider than face), the medially apubescent anepimeron (grey pubescent dorsally and ventrally), the apubescent katepimeron, and the apubescent abdominal tergites.

Etymology.

Greek steno = narrow, cephalos = head. The specific epithet refers to the very narrow ventral face of this species.

Description.

Female. unknown.

Male. Head: black, facial gibbosity brown, in general grey pubescent, white and light brown, regular, cylindrical setae; width distinctly greater than thorax (at postpronotal lobe), interocular distance on vertex distinctly larger than at ventral eye margin; vertex between compound eyes slightly depressed (less than 60° angle on median eye margin), vertex predominantly apubescent, only lateral margin grey pubescent, white setose; ocellar triangle apubescent; facial gibbosity distinct, well-developed and discernible in lateral view, mystax covering entire facial gibbosity, light brown, white ventrally; parafacial area approximately as wide as ½ width of central facial gibbosity (at same level); frons not elevated, medially apubescent, laterally grey pubescent, medially asetose, latero-ventrally brown; occiput grey pubescent, white setose, median occipital sclerite light brown macrosetose; pocl macrosetae absent; postgena sparsely grey pubescent, long, sparsely white setose; clypeus comprised of single sclerite, entirely sclerotized medially, recessed (concave), ventrally simple, posterior to proboscis, laterally connected to face by membranous cuticle; proboscis short, nob-like, occupying approximately ⅓ length of oral cavity, light brown; labellum small, as wide as prementum, as long as prementum, unsclerotized laterally; maxillary palpus cylindrical, light brown, longer than ½ length of proboscis.

Antenna: brown; scape asetose; pedicel white setose dorsally and ventrally; postpedicel indiscernible (broken).

Thorax: black, predominantly grey pubescent; scutum uniformly black, surface macrorugose (distinctly and deeply rugose), predominantly apubescent, paramedian stripes (merging on posterior margin) grey to light brown pubescent and lateral margins grey pubescent, scutal setation comprised of long white to yellow setae in pubescent areas; dc setae pre- and postsuturally white or yellow, acr setae absent, lateral scutal setae white, npl setae 0, spal setae 0, pal setae 0; proepisternum apubescent medially, grey pubescent laterally, long white setose; proepimeron grey pubescent, asetose; antepronotum antero-medially smooth (without any indentation); lateral postpronotum long white setose; postpronotal lobe yellow, grey pubescent, long white setose; scutellum sparsely grey pubescent, discal scutellar setae absent, apical scutellar setae absent; mesopostnotum partly grey pubescent, asetose; anatergite grey pubescent, asetose; katatergite apubescent, long white setose, slightly elevated, smoothly convex; anepisternum grey pubescent, anteriorly asetose, posteriorly asetose, otherwise asetose; katepisternum dorsally grey pubescent, ventrally apubescent, asetose; anepimeron dorsally and ventrally grey pubescent, median stripe apubescent, asetose; katepimeron apubescent, asetose; meron grey pubescent, median stripe apubescent or white pubescent, median stripe apubescent, asetose; metakatepisternum large; metanepisternum grey pubescent, asetose; metepimeron brown (same color as T1), sparsely grey pubescent, long white setose, ± flat, infra-halter sclerite absent.

Legs: yellow to brown, setation comprised of white setae and brown macrosetae; pro coxa sparsely grey pubescent, long white setose; mes coxa sparsely grey pubescent, long white setose; met coxa laterally unsclerotized (membrane between coxa and metakatepisternum clearly visible), sparsely grey pubescent, long white setose; met trochanter setose medially; pro + mes femur yellow, met femur brown, evenly clubbed in distal ¾, macrosetose, 1 antero-ventral and 1 postero-ventral row of macrosetae, 2 macrosetae anteriorly distally, postero-ventrally sparse, long white erect setose; pro tibia straight; mes tibia straight; met tibia laterally arched, met tibia cylindrical with distinct ventral keel terminating into distinct spur, postero-laterally short white, appressed setose; pro + mes tarsomere 1 approximately as long as individual tarsomeres 2, 3, or 4, met tarsomere 1 as long as individual tarsomeres 2, 3, or 4; pulvillus well-developed on pro and mes legs, smaller on met legs; setiform empodium absent.

Wing: length = 5.7 mm; hyaline throughout, veins yellow, microtrichia absent; cells r1, r4, m3, + cua closed, r5 open; C terminating at junction with M1 (or M1+M2); Sc long, terminating in C proximal to r-m; R4 terminates in R1; R5 terminates in R1; auxiliary vein (R3) at base of R4 absent; R4 and R5 widest apart medially; r-m distinct, R4+5 and M1 apart, connected by crossvein; M1 curves slightly anteriorly at r-m, M1 (or M1+M2) terminates in C; base of M3+M4 present, M3+M4 not terminating together in C (not reaching wing margin), M4 and CuA split proximally to m-cu (cell m3 narrow proximally); CuP straight, cell cup wide, CuP and wing margin further apart proximally than distally; alula well-developed; halter light yellow, pubescent, asetose.

Abdomen: brown, setation comprised of scattered short white setae, T2-4 parallel-sided and not constricted waist-like, T surface entirely smooth; T1-7 dark brown dorsally, brown laterally, posterior margins yellowish; T apubescent; T1-2 long white setose, T3-7 short white setose; S1-5 yellow with white posterior margins, S6-8 light brown; S apubescent; S1 asetose, S2-7 sparsely white setose; bullae on T2 transversely elongate, light brown, surface entirely smooth, T2 surface anterior to bullae smooth.

♂ abdomen and terminalia: T1-7 well-developed, entirely sclerotized, T8 postero-medially weakly sclerotized, with anterior transverse sclerotized bridge connecting lateral sclerites. ♂ terminalia not dissected.

Type locality.

Zimbabwe: Mashonaland East: Kotwa, Chimana Causeway (17°06'00"S, 032°38'00"E, -17.1, 32.63333).

Material examined.

Zimbabwe: Mashonaland East: 1♂ Kotwa, Chimana Causeway , 17°06'00"S, 032°38'00"E, 1986-08-05, Lillig, M., Potel, S. ( AAM-003060 , Holotype, SNSB-ZSM) View Materials GoogleMaps .

Distribution, biodiversity hotspots, phenology, and biology.

Known only from the type locality in north-eastern Zimbabwe (Fig. 56 View Figure 56 ). A rarely collected species known only from a single specimen and collecting event in 1986 (Table 1 View Table 1 ). The species is not known to occur in any currently recognized biodiversity hotspot. Adult flies are active in late winter (Table 2 View Table 2 ), which corresponds to the dry season and lower temperatures (data for Mount Darwin, Zimbabwe, see https://worldweather.wmo.int/en/city.html?cityId=956). Nothing is known of the biology.