Stilobezzia (Acanthohelea) xerophila, Cazorla, Carla G. & Spinelli, Gustavo R., 2010

Cazorla, Carla G. & Spinelli, Gustavo R., 2010, Four new Neotropical species of Stilobezzia (Acanthohelea) Kieffer (Diptera: Ceratopogonidae), Zootaxa 2669, pp. 45-56 : 52

Stilobezzia (Acanthohelea) xerophila n. sp.

( Figs. 26–33 , 38 , 39 )

Diagnosis. The only species of Neotropical Stilobezzia (Acanthohelea) with legs dark brown except base and apex of femora with pale rings, male flagellomeres 1–10 pale brown and 11–13 contrastingly dark brown and male abdomen pale brown with genitalia dark brown.

Male. Head. Dark brown. Antenna as in Fig. 26 ; flagellomeres 1–10 pale brown, 11–13 dark brown; antennal plume brown, poorly developed; antennal ratio 0.69–0.80 (0.73, n= 8). Maxillary palpus brown; third segment stout with apical sensory pit; palpal ratio 2.75–3.25 (3.03, n= 8).

Thorax. Scutum dark brown, humeral areas sligthly paler; scutellum sligthly paler, 4 strong setae, 2–3 thiner ones; postscutellum dark brown. Legs dark brown, bases and apices of femora and tibiae with pale rings; tarsomeres pale; hind tibial comb with 6 spines; prothoracic TR 1.89–2.29 (2.10, n= 8); mesothoracic TR 2.12–2.57 (2.36, n= 8); metathoracic TR 2.00–2.8 (2.10, n= 8). Wing ( Fig. 27 ) lenght 0.94–1.12 (1.00, n= 8) mm; width 0.37–0.44 (0.39, n= 8) mm; membrane slightly infuscated, anterior veins brown, cubital fork distal to level of beginning of r-m; dense macrotrichia on costa, scarce on R1, R2, M1, abundant on distal margin of r3, scarce on m1; first radial cell narrow; second 2 times longer than first. Halter whitish.

Abdomen. Pale brown. Genitalia ( Figs. 28–29 , 38 ) dark brown; tergite 9 produced beyond level of end of gonocoxite, progressively narrowing distad, posterior margin rounded; cercus stout, sligthly divergent; sternite 9 folded in the available specimens. Gonocoxite stout, 1.56 times longer than greatest breath, inner margin with short protuberance. Gonostylus 1.24 times shorter than gonocoxite, straight with pointed apex.

Parameres separated, subparallel, sclerotized, articulated to stout, trilobed apodeme; each with basal portion slender, posteromedian process broad on mid portion, tapering to pointed apex. Aedeagus represented by two slender, convergent sclerites.

Female. Similar to male, with usual sexual differences.

Head. Antenna as in Fig. 30 , flagellomeres dark brown, bases paler; antennal ratio 0.89–0.95 (0.91, n= 5). Maxillary palpus ( Fig. 31 ) brown; palpal ratio 2.60–3.25 (2.85, n= 6). Mandible with 7 teeth.

Thorax. Scutellum with 4 strong setae; hind tibial comb with 6 spines; prothoracic TR 2.17–2.33 (2.22, n= 5); mesothoracic TR 2.40–2.52 (2.46, n= 5); metathoracic TR 2.28–2.42 (2.31, n= 5); claws as long as fifth tarsomere. Wing ( Fig. 32 ) length 1.02–1.19 (1.11 n = 7) mm; width 0.48–0.52 (0.50, n= 7) mm, dense macrotrichia on costa, R1, M1, M2, scarce on R2, R3, abundant on distal 1/3 of r3, m1, scarce on margins of m2, cua1; second radial cell 2.25 times longer than first.

Abdomen. Pale brown, segments 8–10 dark brown. Genitalia as in Fig. 33 ; anterior margin of sternite 8 convex, posteromedian excavation U-shaped; sternite 10 short with 3–4 pairs of setae; cercus rounded; two pyriform spermathecae with short necks, measuring 4.8 x 3.0 µm, 4.2 x 3.0 µm; rudimentary third present.

Distribution. Argentina (Salta, Tucumán, San Luis and Córdoba provinces) ( Fig. 39 ).

Types. Holotype male, allotype female, Argentina, Salta prov., Cafayate, Motel del ACA, 27-III-2005, G. Spinelli, light trap. Paratypes: 8 males, 9 females, as follows: same data as holotype 1 male, 1 female; Salta prov., Ojo de Agua, km 1640 Ruta Nacional 9, 23-III-2005, G. Spinelli, 1 male, red; Tucumán prov., Tafí del Valle, 19-I-2000, G. Spinelli, 1 female, light trap; Córdoba prov., Capilla de Monte, 7-III-2006, D. Carpintero, 2 males, 2 females, light trap; 4 km NW Cura Brochero 17/ 29-II-2004, H. López, 1 male, light trap; Río San Antonio, paraje Las Jarillas, 31º 32’ 02.8’’ S, 64º 33’ 01.7’’ O, 820 m, G. Spinelli, 3 males, 4 females, light trap; same data except Malaise trap, 1 female; San Luis prov., Merlo, 14/ 15-XI-2007, G. Spinelli, 1 female, CDC light trap.

Discussion. Stilobezzia (A.) xerophila sp. n. is similar to S. (A.) guarani sp. n. Characters for distinguishing both species my be found in the discussion under the latter species.

Figures

FIGURE 39. Distribution of Stilobezzia (Acanthohelea) guarani, S. (Acanthohelea) monopicta, S. (Acanthohelea) paranaense and S. (Acanthohelea) xerophila.

FIGURE 26 – 33. Stilobezzia (Acanthohelea) xerophila sp. n., 26 – 29 male; 30 – 33 female; 26 — antenna, 27 — wing, 28 — genitalia (ventral view), 29 — parameres removed, 30 — antenna, 31 — maxillary palpus, 32 — wing, 33 — genitalia (dorsal view). Scale bars: 0, 0 5 mm.

FIGURE 34 – 38. Stilobezzia (Acanthohelea) guarani sp. n., 34 — scutum, 35 — male genitalia; Stilobezzia (Acanthohelea) monopicta sp. n., 36 — male genitalia; Stilobezzia (Acanthohelea) paranaense sp. n., 37 — male genitalia; Stilobezzia (Acanthohelea) xerophila sp. n., 38 — male genitalia. Scale bars: 0, 0 5 mm.