Silba tsifama, Macgowan & Tschirnhaus, 2024

Macgowan, Iain & Tschirnhaus, Michael Von, 2024, Records of Lonchaeidae (Diptera, Cyclorrhapha) from Togo and other African countries, with descriptions of new species, Zootaxa 5514 (1), pp. 1-27 : 13-14

Silba tsifama sp. nov. ( Figures 31–33 )

Description: Holotype male: Head: Eye bare. Frons sub—shining black, covered with light microsculpture, frontal and interfrontal setulae short, not more than 0.1x as long as orbital seta, longer along margin with lunule. Orbital plate shining blue-black, bare apart from the orbital seta. Ratio of frons width at narrowest point to eye width 1.0:2. Lunule with a brownish ground colour, covered in grey pollinosity, as to a slight extent are the face and parafacial. Antenna entirely black, reaching down to mouth margin. postpedicel length to depth ratio 2.3:1 Arista yellow basally, plumose, ratio of plume width at maximum to depth of postpedicel 0.9:1. Anterior genal setulae in a single row of 6 along mouth margin, the basal of these strong and slightly curved, the strongest setula on the genae.

Thorax: Scutum shining black, with dense black setulae approximately 0.25x length of orbital seta.Anepisternum with a vertical row of three anterior and three posterior setae, remainder of sclerite with a scattering of setulae which are approximately 0.5x as long as the setae. Katepisternum with a single strong seta located near dorsal margin, approximately six short setulae lying anterior to the seta otherwise the sclerite almost bare. Proepisternum with a single seta, proepimeron also with a single seta which is approximately 0.6x the length of that on the proepisternum. Scutellum, disc shining greyish — black, marginal setae missing but with 1–2 short setulae on each side between lateral and apical setae, two between apical setae. Calypter pale with a white fringe. Wing slightly fumose, veins light yellow, wing length 3.5mm. Legs completely black.

Male terminalia: In lateral view epandrium approximately 1.5x higher than wide, bearing strong setae on ventral margin and over much of the ventral surface. Cercus relatively small, approximately 0.25x height of epandrium, bearing long, strong setae along posterior and ventral margins. In ventral view a long, thin posteriorly directed process of the postgonite lying parallel to the phallus on each side slightly sinuate, pointed apically and just slightly wider than the apical part of the phallus, reaching posteriorly beyond the apex of the latter. Surstylus extending anteriorly from the shell of the epandrium as a boot-like process, medial margin slightly serrated and creased, bearing a row of seven small, black prensisetae of uniform size near posterior margin. Pregonite setulose on posterior surface. Phallus; a simple J-shaped long, thin tube, in ventral view slightly expanded just before apex.

Female: As in male but with the usual sexual differences. Aculeus gently tapering to a rounded tip, three lateral setulae on the apical segment.

Diagnosis. The combination of a single seta on the katepisternum and, in the male genitalia, the long, thin lateral processes arising apparently from the hypandrium make this species easily distinguishable from other members of the genus. The single seta on the katepisternum also allows female specimens collected at the same locality to be confidently associated with the male.

Type material. Holotype: ♂. TOGO: Région du Centre: Tsifama W of Diguina Konta (SW of Blitta), at Kpentsro creek. 28.4.200 8, 8.1647N 0.8077E, 575m Biotope: Remains of secondary rainforest, aspirated from spittle droplets on Anubias gigantea ( Araceae ), leg. M. von Tschirnhaus. Specimen deposited in SDEI; SDEI-Dip-01005.

Paratype: 1♂ with the same data as the holotype. Specimen deposited in NMS; NMS- 10022322 .

Additional material: 3♀, Specimens with the same data as the holotype deposited in NMS; NMS- 10022313, 10022331 & 10022304 .

Etymology. The specific epithet refers to the town of Tsifama where the type material was collected

Figures

FIGURES 31–33. Silba tsifama sp. nov. 31. Epandrium and associated structures, lateral view. LP = lateral process. 32. Same, ventral view. 33. Internal view of surstylus.