Corethrella (Corethrella) edwardsi Lane

Published, First, 2008, The Frog-Biting Midges of the World (Corethrellidae: Diptera), Zootaxa 1804, pp. 1-456 : 153-155

Corethrella (Corethrella) edwardsi Lane

Corethrella edwardsi Lane 1942:126 . Type locality: Salobra, Mato Grosso, Brazil. Holotype ♀ (DEFS). Lane 1953: 91.

DIAGNOSIS: Male and female adults: only extant species of Corethrella in the New World with the wing with four transverse bands, with one of these bands just distal to the arculus and another situated subapically (with no dark scales on these veins extending to the apex of the wing) (Figs. 64H, 70N), with the halter pale or light brown (light than that of the scutellum) and with the hind tibia with both basal and apical darker pigmentation ( Fig. 54B).

DESCRIPTION: Male adult. Descriptive statistics: see Tables 2–5. Head: Outline in anterior view laterally elongate (as in Fig. 12G). Four large setae on frons between ventromedial area of ommatida (as in Fig. 16G). Antenna light brown; pedicel with at least one distinctive, more elongate, stout, dorsal or dorsolateral seta; flagellomeres as in Fig. 23H, sensilla coeloconica distributed as in Table 1; flagellomere 13 with welldeveloped apical bifurcation. Palpus pale to light brown, in some with apical portion or all of segment 5 more darkly pigmented; segment 3 of nearly constant width. Thorax (as in Fig. 54B): Dark brown. Posterior portion of dorsocentral row with group of about 3 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. 64H): Apex of R 2 equal to apex of M 1. Anterior margin with differently, discretely pigmented scales (indicating anterior margins of transverse bands), with four bands of dark scales: basal, subbasal, midlength and subapical, with latter not extending to apex of wing; veins (other than costa and wing margin) with well-developed scales. Halter pale to light brown, lighter than scutellum. Legs (as in Fig. 54B): Dark brown, with apical 1/3 of hind femur more lightly pigmented, hind tibia with basal, apical darker, non-discrete 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. 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. 80A): Dark brown. Genitalia (Fig. 95A): Gonocoxite dark brown basally, with apical 2/3 more lightly pigmented, gently tapering; anteromedial area with spicules similar in length to those elsewhere on gonocoxite; with well-defined dorsal row of setae, with seta 2 thicker than others, 1,3 thicker than 4, 5; 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) basal 4/5 straight, apical 1/5 evenly curved, basal half thicker, apical half slender, tapered apically; one elongate, slender subbasal seta, situated anteriorly or anteroventrally; apical seta slender, elon- gate, 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. 16G). Antenna medium brown; with flagellomeres as in Fig. 30K, sensilla coeloconica distributed as in Table 1. Clypeus ( Fig. 18W) squarish. Mandible with small, pointed teeth. Palpus as in Fig. 35C. Wing (Fig. 70N). Legs: Claws of each leg equal to those of others; equal on each leg, simple (without inner teeth). Abdomen: Dark brown with, in some, segments 8, 9 slightly darker. Cercus dark brown.

Pupa. Mostly undescribed. Thorax: Scutum, metathorax without spherical sensory pits. Respiratory organ (Fig. 103A): Tubular, with apical portion flattened. Abdomen (Fig. 109B): Segments 3–7 not expanded laterally. Paddle long, slender; apicodorsal thick spine articulating; apicoventral seta longer than thick spine.

Larva. Undescribed.

Egg. Unknown.

DISTRIBUTION AND BIONOMICS: Corethrella edwardsi is known from Costa Rica to Colombia, Guyana, and Brazil (Fig. 128) at altitudes ranging from 5– 180 m. Adult specimens have been collected using light and frog-call traps. The Costa Rican specimens from 5 km NE Tárcoles were all collected with a light trap beside a lagoon, while running a frog-call trap ( Hyla gratiosa ) nearby, which did not collect any. Bernal et al. (2006), however, found this to be the most common species at Gamboa, Panama (9°07.0'N, 79°41.9'W) in frog-call traps using Physalaemus pustulosus . These workers also collected the species with taped calls of Dendropsophus microcephalus (pers. obs.), and H. gratiosa (pers. obs.).

The serrate mandibles of the female adults and their attraction to frog calls suggest that they feed on frog blood in nature. The specimens from the Belkin “Mosquitoes of Middle America” project are identified in Table 12.

The male and female from Demerara Guyana were reared from a canal, the female from Corentyne, Guyana from a “hole in ground”, and the male and female from Rio Chagres, Panama from a lake margin.

TAXONOMIC DISCUSSION: Males and females were associated through the shared presence of a common pigmentation pattern and were collected together in Costa Rica, Panama and Guyana; at the latter two locations, males and females were reared from similar larvae and pupae.

Lane (1942) designated a female holotype and 36 female paratypes for C. edwardsi . I have reexamined the holotype and 14 paratypes (now all on microscope slides). It is uncertain where the remaining 22 paratypes are. The one male specimen from Colombia differed in having a basally more pale gonocoxite than other specimens studied. There are associated larval and pupal exuviae for the male and female from Demerara, Guyana and the male and female from Rio Chagres, Panama ( USNM) .

The specimens of C. quadrivittata listed by Lane (1953:91) from Sooretama, Brazil are here identified as C. edwardsi (2 ♀).

MATERIAL EXAMINED: Holotype, adult female on microscope slide, labeled “ Corethrella edwardsi Lane. 41”, “Holotipo”, “ M. Grosso, Salobra, Exp. C.Z. B., vii, 39”, “1.206”, “S277 T2770” ( DEFS). 14 ♀ paratypes labeled as for holotype (2 BMNH; 8 USNM; 4 DEFS). 13 ♂, 11 ♀, 5 km NE Tárcoles, Costa Rica, 20 m, 2-IX-1993 (10 ♂, 8 ♀, CNCI; 3 ♂, 3 ♀, INBC); 2 ♂, 1 ♀, Teñideros, Caño Negro, Alajuela, Costa Rica, 2- IX-2005 ( INBC); 1 ♂, 1 ♀, each with larval and pupal exuviae, Rio Chagres , 1 km S Juan Mina, Chilibre , Canal Zone , Panama, 25 m, 4-VIII-1972 ( USNM); 2 ♀, Gamboa , Panama, 27 m, VII-1967 ( USNM); 2 ♀, 9°07.0'N, 79°41.9'W, Gamboa , Panama, 27 m, 6-VIII-2003 ( CNCI); 3 ♀, from previous location but 20-VII- 2003 ( CNCI); 1 ♀, from previous locality but 17-VIII-2003 ( CNCI); 1 ♀, from previous locality but 18-VIII- 2003 ( CNCI); 1 ♀, from previous locality but 25-VI-2003 ( XBCP); 1 ♀, from previous locality but 6-VIII- 2003 ( XBCP); 1 ♂, 13 km NE Monteria, Cordoba, Colombia, 10 m, 5-6-X-1969 ( USNM); 1 ♂, 1 ♀ with larval and pupal exuviae, Sophia West Middle Walk canal, Demerara, Georgetown , Guyana, 5 m, 6-XI-1967

( USNM); 1 ♀, Corentyne Berbice, Guyana, 5-X-1962 ( USNM) ; 2 ♀, Parque Sooretama , Cupido, Brazil, 58 m, II-III-1948 ( BMNH) .

DERIVATION OF SPECIFIC EPITHET: The name edwardsi was named to honor F.W. Edwards.