Bezzia ventanensis Spinelli

Spinelli, Gustavo R., Ronderos, María M. & Cazorla, Carla G., 2012, A new species of Bezzia Kieffer from Argentina (Diptera: Ceratopogonidae), Zootaxa 3232, pp. 62-68 : 62-64

Bezzia ventanensis Spinelli , n. sp.

( Figs. 1 –25)

Diagnosis. The only species of Neotropical Bezzia in which male and female adults have short palpus, 0–1 spines on fore femur, and lacks distinct leg markings, the female has two well developed spermathecae, and the apex of the male parameres is pointed. Pupa: very similar to B. brevicornis from which it can be mainly distinguished by the presence of 13–15 spiracles (23–25 in B. brevicornis ).

Description of male adult ( Figs. 1–3 , 24–25). Similar to female with usual sexual differences. Interocular space with 4 setae; antenna and palpus as in Fig. 1 ; AR (11–13/1–10) 0.55–0.60 (0.58, n = 4). Hind tarsal ratio 1.82–2.20 (2.07, n = 4). Wing ( Fig. 2 ) length 1.32–1.40 (1.36, n = 4) mm; width 0.50–0.52 (0.51, n = 4) mm; CR 074.–076. (0.75, n = 4). Genitalia ( Fig. 3 ): tergite 9 reaching distal level of gonocoxites, cercus stout, rounded; sternite 9 0.25 as long as wide, with very shallow posteromedian excavation. Gonocoxite stout, tapering distally, nearly twice as long as wide; gonostylus 0.5 as long as gonocoxite, deeply curved hook-like, tip pointed. Parameres (Fig. 24) elongate, anterolateral plates bilobed; distal process slightly narrowing mesally, distal 1/4 with fine pubescence, tip pointed. Aedeagus (Fig. 25) triangular, as long as basal width; basal arch low, extending to 4/5 of total length; lateral arms slender, tapering to blunt tip; ventral surface spiculate distally.

Female adult ( Figs. 4–8 ). Head ( Fig. 4 ). Dark brown. Eyes bare, separated medially by width of about 3–4 ommatidia, with 11–14 setae on interocular space. Antenna ( Fig. 4 ) dark brown, base of flagellomeres pale; scape with 1–2 setae; AR 0.86–1.00 (0.93, n = 3). Palpus ( Fig. 5 ) dark brown; third segment short with few sensilla on inner margin; PR 1.57–1.86 (1.67, n = 3). Proboscis short, 0.3 times width of head. Mandible ( Fig. 5 ) with 7–8 stout teeth.

Thorax ( Fig. 6 ). Dark brown, scutum with narrow longitudinal paler lines, humeral areas paler; small anterior spine present; 4 prealar setae, one postalar; scutellum dark brown, with 6 setae. Legs brownish, hairy; fore, mid femora, fore tibia with insconspicuous, narrow pale rings, fifth tarsomeres dark brown; fore femur with 0–1 ventral spines; hind tibial comb with 7 slender spines; pair of black apical spines on tarsomeres 1–3 of mid leg; ventral palisade setae absent on tarsomere 1 of fore leg; in one row on tarsomeres 1–2 of mid leg and tarsomeres 3 of hind leg, in two rows on tarsomeres 1–2 of hind leg; hind tarsal ratio 2.27–2.33 (2.30, n = 3); fourth tarsomere of each leg cordiform; tarsal claws of each leg small, equal, each with short basal tooth. Wing ( Fig. 7 ), length 1.84–2.14 (2.01, n = 3) mm; width 0.66–0.87 (0.75, n = 3) mm; CR 0.81–0.85 (0.83, n = 3); membrane slightly infuscated; veins pale brown except M dark brown; M narrowly sessile. Halter dark brown.

Abdomen. Pale brown except pleurae dark brown. Sternite 8 sclerotized as in Fig. 8 , with tuft of setae anterior to sclerotization. Allotype and one paratype without gland rods, remaining paratype with single, lightly sclerotized pair of glands rods arising from anterior portion of tergite 6 and extending through segment 5. Two ovoid, strongly sclerotized, unequal spermathecae with short necks ( Fig. 8 ), measuring 114–144 (129, n = 3) by 85 (n =3) µm, 92– 107 (104, n = 3) by 70–74 (71, n = 3) µm; third rudimentary spermatheca present.

Female pupa (Figs. 9–18, 21–23). Total length 4.33–4.76 (4.55, n = 2) mm. Cephalothorax length 1.50–1.64 (1.57, n = 2) mm; width 0.98–1.13 (1.05, n = 2) mm. General coloration uniformly brown. Exuviae pale brown, body surface smooth. Operculum (Fig. 10) with disc wider than long; anterior margin pointed with single row of rounded tubercles; surface mostly smooth with mesal V-shaped band of spicules; dorsomedial area small, wrinkled; each side of mesal portion with wrinkled raised areas; anteromarginal (am) seta (Fig. 10) single, thin, long, located on rounded small tubercle, with pore at tubercle base; posterior margin slightly concave, smooth, only small spicules on mesal portion, OL 0.20 (n = 2) mm, OW 0.23–0.26 (0.245, n = 2) mm; OW/OL 1.15–1.30 (1.22, n = 2) mm. Thorax surface smooth, with mesal soft crest extending between bases of respiratory organs. Two stout, hyaline, anterodorsal seta on rounded tubercles (ad), one medium-sized, other short (Figs. 12–13, 21); one stout, medium-sized, dorsolateral seta (dl) (Fig. 21); 2 dorsomedian setae (dm), one long, thin, other short (Fig. 21); 6 dorsal sensillae (d) (Fig. 11): i, ii, iv elongate, thin setae, iii, v–vi pores. Respiratory organ (Figs. 9, 12) pale brown, short, about 5 times longer than broad, distal 1/3 darker, with 13–15 spiracles, length 0.19–0.25 (0.22, n = 2) mm; pedicel very short, not measurable (Fig. 12). Two long, thin ventromedian setae (vm) (Fig. 15); one short, thin ventrolateral seta (vl), associated pore (Fig. 14). Abdominal segments with dark spots; surface with scattered small spinules; tubercles short with single apex, some of them triangular-shaped. First abdominal segment (Figs. 9, 16, 22) with setae as follows: 2 thin anterior setae, one medium-sized, other long, both on rounded tubercle; 3 lateral setae on two tubercles, one seta long, thin, other short, thin, remaining short, stout; one mesal pore; 2 posterior setae, i very short, iv medium-sized, ii–iii pore. Fourth abdominal sensillar pattern (Figs. 9, 17, 23) as follows: 2 dorsal anterosubmarginal (d.a.s.m.): i, with short, thin seta on stout tubercle, ii with medium-sized, thin setae on small tubercle; 4 dorsal posteromarginal (d.p.m.) sensillae: i, minute seta, iii, iv pore, v medium-sized seta; one lateral anterosubmarginal (l.a.s.m.) short, hyaline seta on small tubercle; 3 lateral posteromarginal (l.p.m.) short, hyaline setae: i, iii on strong, raised base, ii small tubercle on small base; 3 ventral posteromarginal (v.p.m.): i, iii, short, hyaline setae on very small tubercle, ii longer, thiner than others. Anal segment (Figs. 9, 18) with dorsal surface with posteriorly directed spicules, extending to apicolateral processes. Apicolateral processes (Fig. 18) moderately short, nearly straight, base wide, extreme tip darkish, each with tuft of small, dark setae; length 0.32–0.34 (0.33, n = 2) mm, width 0.16–0.26 (0.21, n = 2) mm, apicolateral process length 0.11–0.13 (0.12, n = 3) mm.

Male pupa (Figs. 19–20). Similar to female with usual sexual differences; total length 4.01–4.40 (4.20, n = 2) mm. Operculum (Fig. 19) with stouter, rounded spicules, OL 0.208–0.223 (0.215, n = 2) mm; OW 0.223–0.238 (0.230, n = 2) mm. Respiratory organ length 0.24–0.26 (0.25, n = 2) mm. Anal segment (Fig. 20) length 0.342 (n = 2) mm, width 0.22–0.25 (0.235, n = 2) mm, apicolateral processes length 0.11–0.13 (0.12, n = 2) mm (Fig. 20).

Type material. Holotype male with pupal exuviae, labeled “ Holotype Bezzia ventanensis Spinelli , Argentina, Buenos Aires, Sierra de la Ventana, Reserva provincial Tornquist, arroyo de la Clausura, 38º 02' 46.1'' S, 61º 59' 10.1'' W, 4/ 7-XII-2007, P. Marino-C. Cazorla, Malaise trap ( MLPA)”; allotype female with pupal exuviae, same data except 520 m, 12-XII-2010, A. Siri, collected as pupa and reared in laboratory ( MLPA). Other paratypes, 3 males, 2 females, as follows: same data as holotype, 1 male, 1 female ( MLPA); same data except 21-III-2007, 2 males, 1 female (with pupal exuviae), C. Cazorla, collected as pupa and reared in laboratory ( MLPA).

Distribution. Known only from the type-locality.

Bionomics. The pupa of this new species was collected in the same place as Parabezzia balseroi Spinelli & Grogan. Bezzia ventanensis completes its development in 8 days when placed in cotton-stopper vials individually, at a lab T 22°C–26°C (24° C, n = 4).

Figures

FIGURES 1 – 8. Bezzia ventanensis Spinelli, adult—Figs. 1 – 3: male. Figs. 4 – 8: female. Figs. 1, 4: head. Figs. 2, 7: wing. Fig. 3: genitalia. Fig. 5: mouth parts. Fig. 6: thorax. Fig. 8: tip of abdomen. Scale bars 0.05 mm.