Downeshelea cebacoi (Lane & Wirth)

Felippe-Bauer, Maria Luiza, Silva, Tiago Do Nascimento Da, Ribeiro, Enaly Silva & Borkent, Art, 2011, A new species of Downeshelea Wirth & Grogan and a redescription of the male of Downeshelea cebacoi (Lane & Wirth) (Diptera: Ceratopogonidae), Zootaxa 2780, pp. 20-28 : 25-28

Downeshelea cebacoi (Lane & Wirth) , male redescription

Figs. 15–24

Monohelea cebacoi Lane and Wirth 1964: 218 (in part, specimens from Panama)

Downeshelea cebacoi: Wirth and Grogan, 1988: 51 (in list of World species of Downeshelea ).

Diagnosis. Only species of Downeshelea with dark spots on the apical portion of r3 and m1, with fore-, midfemora yellowish brown ( Fig. 20 ), and the mid portion of each paramere sinuous and the slender distal portion directed posteriorly ( Fig. 23 ).

Male. Head. Brown. Eyes ( Fig. 18 ) bare, moderately separated. Antenna ( Fig. 16 ) with pedicel brown; flagellomeres pale, 2–9 somewhat barrel-shaped, 10 about 3x longer than wide, 11–13 darkest, elongate; antennal ratio 1.03–1.10 (1.08, n=5); palpus ( Fig. 17 ) brown; segment 3 cylindrical, slightly swollen on mid portion, with moderately broad, deep sensory pit near midlength; palpal ratio 2.2–2.6 (2.3, n=5).

Thorax. Brown, without definite pattern in slide mounted specimens. Wing ( Fig. 15) similar to wing of D. lanei ; wing length 1.10–1.40 (1.16, n=6) mm; breadth 0.37–0.45 (0.40, n=6) mm; costal ratio 0.74–0.76 (0.75, n=6). Halter stem pale, knob brown, in some specimens brown only on apical portion of knob. Legs with femora and tibiae ( Fig. 20 ) yellowish brown, hind femur darker on subapical portion, hind tibia darker on proximal half and apical 1/5, in some specimens hind tibia yellowish brown, without define pattern; femorotibial joint areas yellowish; fore-, hind tibiae with apical spur, longer in foreleg; hind tibial comb with 6–7 large setae ( Fig. 19 ). Tarsi ( Fig. 21 ) pale, pilose; palisade setae in single row on hind tarsomere 1; fore-, hind tarsomere 1 with one basal, one apical spine; mid tarsomere 1 with 2 basal, 2 apical, 2–3 other ventral spines; apical spines of tarsomeres 2–4 of fore-, mid-, hind legs: 2-2-2, 2-2-2, 1-1-2, basal spines absent; fore-, mid-, hind tarsal ratios 2.4, 2.5, 2.2 (n=5).

Abdomen. Brown. Terminalia ( Fig. 22–24 ): tergite 9 tapering gradually distally to broad, quadrate apex, with slender apicolateral process; sternite 9 spiculate except on basal portion, posterior margin with narrow, moderately convex median extension bearing two long setae. Gonocoxite straight, moderately stout, 2.4x longer than basal width; gonostylus nearly straight, 0.60 length of gonocoxite, proximal ½ moderately pilose. Parameres ( Fig. 23 ) 1.3x longer than aedeagus, broadly fused basally; stem slender, sinuous at mid length, distal portion long, hyaline, straight, slender process posteriorly directed. Aedeagus ( Fig. 24 ) subtriangular, basal arch very shallow, lateral arms not pronounced, mesal portion with heavily sclerotized area extending from base of basal arms to medioapical region, distal portion with heavily sclerotized margins, moderately narrow apicomesal excavation with two short, slender, pointed, membranous lobes.

Distribution. Downeshelea cebacoi is known from 15 meters in elevation in Almirante, Bocas del Toro Province in Panama to 1450 meters in Puntarenas Province, Costa Rica. The single male from Estación Altamira is from well developed cloud forest.

Specimens examined. Holotype male adult, pinned, with genitalia in drop of Canada Balsam on celluloid strip on pin, labeled " Holotype 3, Monohelea cebacoi Lane & Wirth ", "Almirante Pan Bocas del Toro Pr Jan 1953 ", "F.S. Blanton collector" (USNM); 1 male adult paratype, Canada Balsam on four celluloid strips on pin. PAN- AMA, Bocas del Toro Provincia, Almirante, IX. 1952, F.S. Blanton col., labeled " Monohelea cebacoi , paratype, John Lane det.1961" (#14944, FSPC); 2 males COSTA RICA, Prov. Limón, Est. Biol. Hitoy Cerere, Send. Toma de Agua, 100m, 17.IV–08.V.1999, F. Umana, Malaise Trap, LN 184600/643400, #52757, CD5090 (INBC; CNCI); 1 male, Valle del Silencio, Sendero Espavel, 220m, 17.II–17.III.2000. F. Umana, Malaise Trap, LS 401558 570460, #55286 (CCER); 1 male, Prov. Puntarenas, Buenos Aires, Estación Altamira, Sendero Los Gigantes, 1450 m, 03– 22.II.2000, D. Rubi. Amarilla, LS 331700 572200, #54808, CD5368 (INBC); 1 male, Golfito, P.N. Corcovado, Estación Los Patos, Send. a Sirena, 70m, 25.XII.2000 – 13.II.2001, J. Azofeifa, Malaise Trap, LS 509200 275700 #61323 (INBC); 1 male, Prov. Cartago, P.N. Barbilla, Send Principal a Rio Barbilla, 400–500 m, 19.VIII.2001, E. Rojas, F. Umana, Red de Golpe, LN 216110 597123, #63930 (INBC).

Discussion. The presence of D. cebacoi at lower elevations in Costa Rica and Panama in areas of lowland rainforest suggests that this species is more broadly distributed north and south of its known distribution.

We were unable to locate the female allotype, also from the type locality, said to be in the USNM by Lane & Wirth (1964).

Figures

FIGURES 16 – 21. Downeshelea cebacoi (Lane & Wirth), male. 16. Antenna; 17. Palpus; 18. Dorsal portion of head capsule, anterior view; 19. Hind tibial comb; 20. Femora and tibiae (left to right) of fore-, mid- and hindlegs; 21. Tarsi (left to right) of fore-, mid- and hindlegs.

FIGURES 22 – 24. Downeshelea cebacoi (Lane & Wirth), male. 22. Terminalia, aedeagus and parameres removed; 23. Parameres; 24. Aedeagus.