Corethrella (Corethrella) drakensbergensis Borkent, 2008

Published, First, 2008, The Frog-Biting Midges of the World (Corethrellidae: Diptera), Zootaxa 1804, pp. 1-456 : 57-58

Corethrella (Corethrella) drakensbergensis Borkent , new species

DIAGNOSIS: Male and female adults: only extant species of Corethrella in the Afrotropical Region with a plain wing (Figs. 61F, 66J) and a medium to dark brown thorax ( Fig. 39C).

DESCRIPTION: Male adult. Descriptive statistics: see Tables 2–5. Head: Outline in anterior view somewhat circular (as in Fig. 6G). Two large setae on frons between ventromedial area of ommatida (as in Fig. 16B). Antenna uniformly medium brown (flagellomeres 12, 13 missing); pedicel without distinctive, more elongate, stout, dorsal or dorsolateral setae; flagellomeres as in Fig. 19G, sensilla coeloconica distributed as in Table 1; flagellomere 13 with well-developed apical bifurcation. Palpus brown (segment 5 missing); segment 3 swollen apically. Thorax (as in Fig. 39C): medium brown with pleura slightly more pale or with ventral portion of katepisternum and ventral portion of anepimeron paler. Posterior portion of dorsocentral row with 2 elongate setae situated somewhat lateral to one another. Prescutal suture elongate, thick, uninterrupted, extending to near dorsocentral row of setae. Anterior anepisternum divided diagonally by sinuous suture, dorsal portion about equal to ventral portion. Ventral portion of posterior anepisternum triangular, uniformly brown, with anterodorsal margin not thick. Wing (Fig. 61F): Apex of R 2 distal to apex of M 1. Plain, without pattern of pigmented veins; veins (other than wing margin) denuded. Halter paler than scutellum. Legs (as in Fig. 39C): Femora, tibiae, foreleg tarsus uniformly medium brown; mid-, hind leg tarsi missing. Femora armature mostly missing but a few simple setae present (except for some apically expanded setae in patch of whip-like setae on posterior portion of hind tibia). Presence of thick, subapical setae on tarsomeres 1–3 uncertain. Foreleg claws unequal (as in Fig. 75D). Each claw without inner tooth. Anterior claws of each leg without a basal prong. Foreleg third tarsomere longer than fourth tarsomere. Claws of mid-, hind legs missing. Empodia thick. Abdomen (Fig. 76F): Uniformly medium brown. Genitalia (Fig. 84B): Gonocoxite uniformly medium brown, gently tapering; anteromedial area with spicules similar in length to those elsewhere on gonocoxite; with well-defined dorsal row of setae, with anterior setae of similar thickness as some other setae on gonocoxite, with posteriormost seta slightly thicker, with row curving posteromedially with posteriormost seta of row positioned dorsomedially. With one dorsomedial stout seta, tapering from base. Gonostylus (in retracted position) straight, curved subapically; of more or less equal thickness for entire length, tapered apically; one elongate, thick subbasal seta, situated ventrally; with thick, blunt apical peg. Aedeagus slender, elongate, tapering gradually to apex, pointed apically, with lateral margins fused at very apex.

Female adult. Descriptive statistics: see Tables 6–11. As for male, with following differences. Head: Coronal suture elongate, extending ventrally past ommatida (as in Fig. 16B). Antennal flagellomeres as in Fig. 26D, sensilla coeloconica distributed as in Table 1 (flagellomeres 10–13 missing). Clypeus ( Fig. 17I) elongate. Mandible with large, pointed teeth. Palpus as in Fig. 33J (segment 5 missing). Wing (Fig. 66J). Legs ( Fig. 39C): As for male but with fore-, midtarsi missing; hind tarsus medium brown. Claws of hind leg simple (without inner teeth). Abdomen: Cercus medium brown.

Immatures. Unknown.

DISTRIBUTION AND BIONOMICS: Corethrella drakensbergensis is known only from the type locality in South Africa (Fig. 114) at an altitude of 1500 m. The specimens were collected with a Malaise trap near a stream in Rainbow Gorge Forest , a protected area with humid montane forest (S. Peck, pers. comm.) .

TAXONOMIC DISCUSSION: Males and the single female were associated through their shared pigmentation pattern and were collected at the same locality and date. All three specimens of C. drakensbergensis were badly rubbed and had parts of the legs and antennae missing. The overall darker wing of this species is likely due to discoloration from being stored in a large Malaise trap sample with darkened alcohol before being extracted.

TYPES: Holotype, male adult on microscope slide, labeled " HOLOTYPE Corethrella drakensbergensis Borkent , 75 km SW Estcourt Cathedral Peaks For. Stn., Natal , South Africa, 7-31-XII-1979, S. and J. Peck, 1500 m ” ( NMSA) . Allotype, female adult on microscope slide, labeled as for holotype ( NMSA). Paratype: 1 ♂, labeled as for holotype ( CNCI) .

DERIVATION OF SPECIFIC EPITHET: The name drakensbergensis reflects the type locality in the Drakensberg Mountains of South Africa .