Stilobezzia (Acanthohelea) pabloi Cazorla and Spinelli, 2014

Cazorla, Carla G. & Spinelli, Gustavo R., 2014, A revision of the Patagonian predaceous midges of the subgenus Acanthohelea of Stilobezzia excluding the S. (A.) edwardsi group (Diptera: Ceratopogonidae), Journal of Natural History 49 (3), pp. 155-209 : 182-183

Stilobezzia (Acanthohelea) pabloi Cazorla and Spinelli sp. nov.

( Figures 8 , 21 )

Diagnosis

The only Patagonian species of Stilobezzia (Acanthohelea) with stout aedeagal sclerites, broadening distally with small mesal notch. Female unknown.

Male. Head ( Figure 8A ). Dark brown. Antennal flagellum brown, flagellomeres 1–10 with pale ring above the plume; plume brown, poorly developed; antennal ratio1.56– 1.65 (1.60, n = 2). Palpus brown; segment 3 slightly shorter than 5; palpal ratio 3.75– 4.00 (3.87, n = 2).

Thorax ( Figure 8C ). Scutum dark brown, humeral pits pale brown; scutellum pale brown with 6 large setae; postscutellum dark brown; pleura dark brown. Legs brown, hind leg slightly darker; prothoracic TR 1.80–2.11 (2.00, n = 2); mesothoracic TR 2.05–2.10 (2.07, n = 2); metathoracic TR 2.10–2.22 (2.16, n = 2). Wing ( Figure 8B ) length 1.58–2.10 (1.84, n = 2) mm, width 0.60 mm (n = 2), costal ratio 0.72–0.74 (0.73, n = 2); membrane slightly infuscated; second radial cell 2.16× longer than first; cubital fork originating distal to base of r-m cross vein; macrotrichia on costa, R 1, R 2, R 3, sparse on distal margin of r 3, abundant on apex of m 1. Halter pale brown.

Abdomen. Dark brown. Genitalia ( Figure 8D ): tergite 9 extending 0.70 of gonocoxites length, slender, triangular, posterior margin blunt; sternite 9 short, distal margin apparently without posteromedian excavation; sternite 10 spiculate, not produced beyond base of cerci; cerci directed laterad. Gonocoxite stout, 1.80× longer than greatest breadth; gonostylus curved, base stout, slightly narrowing to pointed tip. Parameres divergent; basal apodemes curved; stems contiguous proximally, then slightly divergent, swollen at mid portion, tip ladleshaped. Aedeagus 0.65× length of basal breadth, composed of two sinuous sclerites, each progressively broadening distally, tip sclerotized with small mesal notch.

Female. unknown.

Distribution

Argentina (Neuquen) ( Figure 21 ).

Types

Holotype male, Argentina, Neuquen, Laguna Epulafquen , 21–23 February 2001, G. Spinelli, Malaise trap ( MLPA) . Paratype, 1 male, same data as holotype .

Etymology

This species is named after Dr Pablo Marino, colleague and friend of the Museo de La Plata.

Discussion

This species is similar to S. (A.) mapuche . The latter species differs by the gonostylus greatly curved subbasally over 90° and the aedeagal sclerites with subapical pointed divergent prongs arising from a common base, the proximal one directed laterad and the distal one directed distad.

Figures

Figure 8. Stilobezzia (A.) pabloi Cazorla and Spinelli sp. nov., male: (A) head; (B) wing; (C) thorax (lateral view); (D) genitalia (ventral view), aedeagus and parameres removed. Scale bars 0.05 mm.

Figure 21. Distribution of Stilobezzia (A.) pabloi and Stilobezzia (A.) spinosa.