Corethrella (Corethrella) brunnea Borkent, 2008

Published, First, 2008, The Frog-Biting Midges of the World (Corethrellidae: Diptera), Zootaxa 1804, pp. 1-456 : 56-57

Corethrella (Corethrella) brunnea Borkent , new species

DIAGNOSIS: Male adult: unknown. Female adult: only extant species of Corethrella in the Old World with about 23 setae on the clypeus, a plain wing (no pattern) (Fig. 66I), wing with well-developed scales on all the wing veins (as in Fig. 73D), an entirely dark brown thorax ( Fig. 39B), and halter as dark as the scutellum.

DESCRIPTION: Male adult. Unknown. Female adult: Descriptive statistics: see Tables 6–11. Head: Outline in anterior view uncertain. Coronal suture uncertain (poorly positioned on microscope slide). Two large setae on frons between ventromedial area of ommatida (as in Fig. 16B). Antenna dark brown; pedicel without distinctive, more elongate, stout, dorsal or dorsolateral setae; flagellomeres as in Fig. 26C, sensilla coeloconica distributed as in Table 1; flagellomere 13 with well-developed apical bifurcation. Clypeus squarish (not clearly visible). Mandible with large, triangular teeth. Palpus ( Fig. 33I) dark brown; segment 3 somewhat ovoid, swollen beyond midlength. Thorax ( Fig. 39B): dark brown, pale sclerites around base of wing. 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. 66I): Apex of R 2 equal to apex of M 1. Plain, without pattern of pigmented veins and/or scales; veins (other than costa and wing margin) with well-developed scales. Halter as dark as scutellum. Legs ( Fig. 39B): Uniformly dark brown. With only slender setae, lacking scales (except for some in patch of whip-like setae on posterior portion of hind tibia). Midleg with thick, subapical setae on each of at least tarsomeres 1–3. Claws of each leg equal to those of others; equal on each leg, simple (without inner teeth). Empodia thick. Abdomen: Dark brown. Cercus dark brown.

Immatures. Unknown.

DISTRIBUTION AND BIONOMICS: Corethrella brunnea is known from the type locality in Sarawak, Malaysia (Fig. 116A) at an altitude of about 20 m. The single holotype was collected with a Malaise trap over a stream .

TAXONOMIC DISCUSSION: The holotype is uncleared and undissected on a microscope slide, so that some features could not be studied.

TYPE: Holotype, female adult on microscope slide, labeled " HOLOTYPE Corethrella brunnea Borkent ”, “ Sarawak: 1 st Div., Semongoh For. Res., 1 25' N 110 17'E, 15-19.xi.1976, P.S. Cranston, B.M. 1977-19”, “malaise over stream” ( BMNH).

DERIVATION OF SPECIFIC EPITHET: The name brunnea (brown) refers to the overall coloration of the female of this species.