Corethrella (Corethrella) amabilis Borkent, 2008

Published, First, 2008, The Frog-Biting Midges of the World (Corethrellidae: Diptera), Zootaxa 1804, pp. 1-456 : 115-116

Corethrella (Corethrella) amabilis Borkent , new species

DIAGNOSIS: Male adult: unknown. Female adult: only extant species of Corethrella in the New World with flagellomeres 2 and 3 very short ( Fig. 29C), flagellomeres 7–12 each with one sensillum coeloconicum, a distinct midlength wing band and no dark scales basal to this band (Fig. 69G), thorax dark brown ( Fig. 49A), halter light brown (lighter than scutellum), midfemur dark brown and equal to that of base of hind femur, midfemur without scales, base of hind tibia darkly pigmented (contrasting with pale apex of hind femur) ( Fig. 49A).

DESCRIPTION: Male adult. Unknown. Female adult. Descriptive statistics: see Tables 6–11. Head: Outline in anterior view laterally elongate ( Fig. 10D). Coronal suture short, extending ventrally about midway along area between ommatidia (as in Fig. 16F). Two large setae on frons between ventromedial area of ommatida (as in Fig. 16F). Antenna dark brown); pedicel with at least one distinctive, more elongate, stout, dorsal or dorsolateral seta; flagellomeres as in Fig. 29C, sensilla coeloconica distributed as in Table 1; flagellomere 13 with well-developed apical bifurcation. Clypeus ( Fig. 18B) squarish or somewhat wider than long. Mandible with small, pointed teeth. Palpus ( Fig. 34N) pale; segment 3 somewhat ovoid, swollen at or near midlength. Thorax (as in Fig. 49A): Dark brown, pale sclerites around base of wing, scutellum with darker anteromedial spot. Posterior portion of dorsocentral row with 2 elongate setae situated somewhat lateral to one another. Prescutal suture elongate, interrupted by area of pale cuticle. 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 thick. Wing (Fig. 69G): Apex of R 2 basal to apex of M 1. Anterior margin with differently, discretely pigmented scales (indicating anterior margin of wing band), distinct midlength band present; veins (other than costa and wing margin) with well-developed scales. Halter light brown, lighter than scutellum. Legs (as in Fig. 49A): Medium to dark brown, with fore-, midleg knees pale, hind femur with apical 0.6 pale, hind tibia pale with basal and apical discrete dark brown pigmentation. 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 slender. Abdomen: Medium brown with sternites 1–2 slightly darker, segments 8–9 dark brown. Cercus dark brown.

Immatures. Unknown.

DISTRIBUTION AND BIONOMICS: Corethrella amabilis is known from two localities in the highlands of Costa Rica (Fig. 119A) at an altitude of 1800–1850 m. The three specimens were collected with Malaise traps.

TYPES: Holotype, female adult on microscope slide, labeled " HOLOTYPE Corethrella amabilis Borkent ”, “ Costa Rica, Prov. Cartago, A.C.L.A.P., Paraíso, Pque Nal Tapantí, Sect La Rep. Torre I.C.E. entre Ríos Porras y Villegas. 1800 m, Nov 1996. R. Delgado. Malaise LN186150 560100, #52191, CD5148” ( INBC) . Paratypes: 1 ♀, from type locality but VII-1997 ( CNCI) ; 1 ♀, Est. Santa Elena, Chirripó NP, San Jose , Costa Rica, 1850 m, 20-III–15-IV-1997 ( INBC) .

DERIVATION OF SPECIFIC EPITHET: The name amabilis (lovely) refers to the prettily patterned body of this species (shared with numbers of others).