Dasyhelea scalpela, Grogan, Willliam L., Díaz, Florentina, Spinelli, Gustavo R. & Ronderos, Maria M., 2016

Grogan, Willliam L., Díaz, Florentina, Spinelli, Gustavo R. & Ronderos, Maria M., 2016, The biting and predaceous midges of Guadeloupe (Diptera: Ceratopogonidae). II. Species of the subfamily Dasyheleinae, Zootaxa 4184 (2), pp. 201-254 : 219-222

Dasyhelea scalpela new species

( Figs. 9–10 )

Diagnosis. The only Neotropical species of the grisea group with males having the apex of the paramere scalpedshaped. Females with fore, hind femora with mesal dark spot, fore tibia with mesal dark ring, the subgenital plate arrow-shaped and the spermatheca with neck elongate, stout and oblique.

Male. Head ( Fig. 9 A). Dark brown. Eyes broadly contiguous. Frontal sclerite heart-shaped. Antennal flagellum with flagellomeres 2–9 rhomboidal, 10–13 elongate, 13 longest; antennal ratio 0.83–0.94 (0.89, n=10). Palpus ( Fig. 9 B) moderately short; segment 3 short with scattered capitate sensilla; palpal ratio 1.90–2.18 (1.98, n=10). Scutellum with 6 large, 2 smaller setae. Wing ( Fig. 9 C) moderately slender; membrane hyaline, covered with moderately dense macrotrichia; 2nd radial cell short, well developed; apex of costa, radius perpendicular to wing margin; fork of CuA1 at level of anterior portion of 2nd radial cell; wing length 0.92–1.06 (0.96, n=10) mm, width 0.32–0.34 (0.33, n=10) mm; costal ratio 0.49–0.53 (0.50, n=10). Genitalia ( Figs. 9 D, 10A). Tergite 9 tapering distally, apex truncate, extending beyond apices of gonocoxites; apicolateral process stout, conical with medium-size apical seta; cercus small with 3 setae, 1 medium-size, other 2 shorter. Sternite 9 ( Figs. 9 D, 10B) 0.83 length of greatest width, with narrow deep posteromedian excavation. Gonocoxite stout, 1.48 x longer than greatest width, broadest mesally; gonostylus as long as gonocoxite, very slightly curved, apex bluntly pointed. Gonocoxal apodemes and paramere ( Figs. 9 D, 10C) forming an asymmetrical structure; gonocoxal apodemes moderately slender, bases curved; left apodeme narrowly contacting paramere or separate, right broadly contacting paramere; paramere slender on basal 2/3, distal 1/3 broadened, apex scalped-shaped with recurved, pointed tip. Aedeagus ( Figs. 9 D, 10D) with anterior margin nearly straight, 0.72 length of greatest width; basal arms stout, directed laterally; posterolateral arms slightly divergent, tapering distally, with blunt tips.

Female. Head ( Fig. 9 E). Brown. Eyes contiguous for a distance equal to width of 4 ommatidia. Frontal sclerite broad, bilobed with long, slender ventral projection. Antennal flagellum dark brown; flagellomeres 2–8 vasiform, 9–12 longer vasiform, 13 longest; antennal ratio 0.81–0.92 (0.87, n=5). Clypeus with 5 pairs of setae. Palpus ( Fig. 9 F) moderately short, light brown; segment 3 short with 2 mesal capitate sensilla; palpal ratio 1.63–2.27 (2.03, n=5). Thorax. Scutum dark brown, humeral areas paler; scutellum slightly paler with 7 large, 4 smaller setae. Legs pale brown; fore, hind femora with mesal dark spot, fore tibia with mesal dark ring; femorotibial joints dark; tarsomeres 5 infuscated; hind tibial comb with 6 spines; prothoracic tarsal ratio 2.10–2.54 (2.31, =6), mesothoracic tarsal ratio 2.21–2.54 (2.36, =5), metathoracic tarsal ratio 2.14–2.66 (2.35, =5). Wing ( Fig. 9 G) moderately broad; membrane hyaline with moderately dense macrotrichia; apex of costa, radius oblique; fork of CuA1 at level anterior to base of 2nd radial cell; wing length 0.84–1.02 (0.92, =6) mm, width 0.34–0.44 (0.39, n=6) mm; costal ratio 0.52– 0.58 (0.54, n=6). Halter brown. Abdomen ( Fig. 9 H). Brown. Subgenital plate with anterior portion somewhat arrowhead-shaped, elongate, posterior portion U-shaped, continuous with posterolateral arms; posterolateral arms heavily sclerotized, curved, connected distally by slender sclerite. Spermatheca ovoid, diameter 60 µm, neck elongate, stout, oblique, measuring 46 µm.

Distribution. Guadeloupe.

Type material. Holotype male, allotype female labeled “ Guadeloupe, Basse Terre , Trace des Cretes (D-14), 22-V-2012, R. H. Turnbow, BL trap ” (deposited in FSCA) . Paratypes 20 males, 5 females, as follows: same data as holotype 16 males, 4 females ; same data except NE Pigeon, (16.14404º N, 61.74977º W), 18-V-2012, 3 males ; same data except 23-V-2012, 1 male, 1 female .

Derivation of specific epithet. The species name refers to the unusual scalpel-shaped apex of the male paramere.

Discussion. This new species is very similar to D. flavifrons , but in males of that species, the distal portion of the paramere is bent sharply ventrolaterad and tapers to a blunt point; and females differ by their more broadly elliptical frontal sclerite, yellow halter knob, the subgenital plate that is triangular anteriorly with a lateral posteriorly directed projection, and the neck of the spermatheca is long and straight.

Figures

FIGURE 9. Dasyhelea scalpela n. sp. Holotype male, A – D, Allotype female, E – H. A, E. head. B, F. palpus. C, G. wing. D. genitalia. H. subgenital plate and spermatheca.

FIGURE 10. Dasyhelea scalpela n. sp. Holotype male. A. genitalia. B. sternite 9. C. gonocoxal apodemes and paramere. D. aedeagus. Scale bar: 0.05 mm.