Corethrella (Corethrella) albicoxa Borkent, 2008

Published, First, 2008, The Frog-Biting Midges of the World (Corethrellidae: Diptera), Zootaxa 1804, pp. 1-456 : 137-139

Corethrella (Corethrella) albicoxa Borkent , new species

DIAGNOSIS: Male adult: only extant species of Corethrella in the New World with a pale palpus (as in Fig. 12A), a distinct midlength wing band and with or without more basal dark scales (Fig. 64B), with a dark brown thorax (as in Fig. 52D), dark brown midfemur, base of hind tibia darkly pigmented (contrasting with pale apex of hind femur) (as in Fig. 52D), all femora with slender scales (as in Fig. 74C), and a pale gonocoxite (contrasting with dark segments 8 and 9) (Fig. 79G). Female adult: only extant species of Corethrella in the New World with a distinct midlength wing band and with more basal dark scales on M and, in some, on R (Fig. 70H), with a dark brown thorax ( Fig. 52D), dark brown midfemur, base of hind tibia darkly pigmented (contrasting with pale apex of hind femur), hind femur with basal 0.42–0.55 darkly pigmented ( Fig. 52D), and all femora with slender scales (as in Fig. 74C).

DESCRIPTION: Male adult. Descriptive statistics: see Tables 2–5. Head: Outline in anterior view laterally elongate (as in Fig. 12A). Two large setae on frons between ventromedial area of ommatida (as in Fig. 16B). Antenna pale to light brown, with flagellomeres 11–13 more darkly pigmented in some; pedicel with at least one distinctive, more elongate, stout, dorsal or dorsolateral seta; flagellomeres as in Fig. 23B, sensilla coeloconica distributed as in Table 1; flagellomere 13 with well-developed apical bifurcation. Palpus pale; segment 3 of nearly constant width or somewhat swollen subapically. Thorax (as in Fig. 52D): Dark brown, pale sclerites around base of wing. Posterior portion of dorsocentral row with group of about 7 elongate setae. Prescutal suture short, not extending more than half way to 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 thick. Wing (Fig. 64B): Apex of R 2 basal to apex of M 1. Anterior margin with differently, discretely pigmented scales (indicating anterior margin of midlength band), with midlength band, with darker more basal scales restricted to vein M, some with darker scales on R; veins (other than costa and wing margin) with well-developed scales. Halter medium brown, lighter than scutellum. Legs (as in Fig. 52D): Dark brown with knees of fore-, midlegs pale, basal 0.42–0.55 of hind femur dark, base and apex of hind tibia with discrete dark pigmentation, pale at midlength, at least mid-, hind leg tarsomeres 2–4 with banding. Femora, tibiae with slender scales (also 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. Apices of fore-, midleg fifth tarsomeres undivided, with claws slightly subapical to apical (as in Fig. 75F). Claw of foreleg longer than those of mid-, hind leg. Each claw without inner tooth. Anterior claws of each leg without a basal prong. Foreleg claws unequal. Midleg claws equal. Foreleg third tarsomere shorter than fourth tarsomere. Empodia slender. Abdomen (Fig. 79G): Dark brown. Genitalia (Fig. 93C): Gonocoxite pale to light brown, gently tapering; anteromedial area with spicules similar in length to those elsewhere on gonocoxite; with well-defined dorsal row of setae, with setae 1, 2, 3 thicker than others, in some, seta 2 thicker than others, with row restricted to dorsal portion of gonocoxite. With one dorsomedial stout seta, more or less of even thickness for most of length, tapering near apex. Gonostylus (partially extended) mostly straight, curved near apex, slender, of more or less equal thickness for entire length, expanded apically, rounded to somewhat pointed apically; one elongate, slender subbasal seta, situated anteriorly or anteroventrally; apical seta slender, short, simple. Aedeagus slender, elongate, tapering gradually to apex, pointed apically, with lateral margins fused at 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). Antenna medium to dark brown; with flagellomeres as in Fig. 30F, sensilla coeloconica distributed as in Table 1. Clypeus ( Fig. 18Q) wide. Mandible with small, pointed teeth. Palpus as in Fig. 34 AC. Wing (Fig. 70H). Legs: Claws of each leg equal to those of others; equal on each leg, simple (without inner teeth). Abdomen: Dark brown. Cercus dark brown.

Pupa. Mostly undescribed. Thorax: Scutum, metathorax each with spherical sensory pit (as in Fig. 100A). Respiratory organ (Fig. 102H): Tubular. Abdomen (Fig. 108A): Segments 3–7 somewhat expanded laterally. Paddle only moderately elongate; apicodorsal thick spine articulating; apicoventral seta longer than thick spine.

Larva. Undescribed.

Egg. Unknown.

DISTRIBUTION AND BIONOMICS: Corethrella albicoxa is known from Grenada, Trinidad and Tobago and Venezuela (Fig. 122) at altitudes ranging from 20–1700 m. All adults were reared from bromeliads. The specimens from the Belkin “Mosquitoes of Middle America” project are identified in Table 12.

TAXONOMIC DISCUSSION: Males and females were associated through the shared presence of a distinctive pigmentation pattern and slender scales on the legs and were reared together in both Trinidad and Tobago and Venezuela.

TYPES: Holotype, male adult on microscope slide, larval and pupal exuviae on separate slide, labeled " HOLOTYPE Corethrella albicoxa Borkent ”, “Natl. Rt. 3 NW of Rancho Grande, Maracay, Aragua, Venezuela, 800 m, 16-VIII-1969 ", “ Corethrella sp. 28 USNM”, “VZ 379-60 Venezuela 69–70 Mosq Mid Amer” (USNM). Allotype, female adult on microscope slide, larval and pupal exuviae on separate slide, labeled as for holotype but VZ 379-61( USNM) . Paratypes: 1 ♂ with larval and pupal exuviae from type locality ( USNM) ; 1 ♂ with larval and pupal exuviae, 1 ♂ with pupal exuviae, 1 ♀ with larval and pupal exuviae, 1 ♀ with pupal exuviae, Trail NE of Rancho Grande, Maracay, Aragua, Venezuela, 1100 m, 5-VII-1969 (1 ♂ with pupal exuviae, CNCI; others to USNM) ; 1 ♀ with larval and pupal exuviae, Rancho Grande , Maracay, Aragua, Venezuela, 1100 m, 6-VII-1969 ( USNM) ; 2 ♂, 4 ♀, each with larval and pupal exuviae, Rancho Grande , Maracay, Aragua, Venezuela, 1100 m, 29-XI-1967 (1 ♀, CNCI; others to USNM) ; 1 ♂ with larval and pupal exuviae, Alto de Pipe , Caracas, Miranda, Venezuela, 1700 m, 26-XI-1967 ( USNM) ; 1 ♀ with pupal exuviae, near trail to Fedons Camp from Grand Etang , Mont Quaqua, St. Andrew, Grenada, 600 m, 23-X-1963 ( USNM) ; 1 ♀ with pupal exuviae, St. David , near Matelot, Trinidad and Tobago, 20 m, 12-III-1964 ( USNM) ; 1 ♂, 1 ♀, each with larval and pupal exuviae, St. George , Aripo Valley, Trinidad and Tobago, 300 m, 19-III-1964 ( USNM) ; 1 ♂ with pupal exuviae, as previous locality but 250 m, 20-III-1964 ( USNM) ; 1 ♂ with larval and pupal exuviae, St. George , “Brasso Seco “, Trinidad and Tobago, 500 m, 2-IV-1964 ( USNM) ; 1 ♂ with larval and pupal exuviae, St. George , “Brasso Seco “, Arima-Blanchisseuse Rd. 12 milepost, 500 m, Trinidad and Tobago, 18-III-1965 ( USNM) ; 1 ♀ with larval and pupal exuviae, St. George , “Las Lapas Trace “, Trinidad and Tobago, 600 m, 3-IV-1964 ( USNM) ; 2 ♀, each with pupal exuviae, St. George , Guanapo Valley, “AripoGuanapo Trace 9 milepost “, Trinidad and Tobago, 150 m, 16-IV-1964 ( USNM) ; 1 ♂ with larval and pupal exuviae, St. George , “La Laja Trace “, Trinidad and Tobago, 400 m, 8-IV-1965 ( USNM) ; 1 ♂ with larval and pupal exuviae, St George , “La Laja Trace” 1 mi. from Arima-Blanchisseuse Rd, Trinidad and Tobago, 500 m, 12-III-1966 ( USNM) ; 1 ♂ with pupal exuviae, St George , “Spring Hill Estate “, Trinidad and Tobago, 300 m, 5-III-1966 ( USNM) ; 1 ♀ with larval and pupal exuviae, St George , Lopinot Rd 6 3/4 milepost, 250 m, Trinidad and Tobago, 19-III-1966 ( USNM) .

DERIVATION OF SPECIFIC EPITHET: The name albicoxa (white, coxa) refers to the pale male gonocoxite.