Atrichopogon dactilus Felippe-Bauer

Felippe-Bauer, Maria Luiza, Silva, Tiago Do Nascimento Da & Alves, João Ricardo Carreira, 2012, Two new species of Atrichopogon Kieffer from Rio de Janeiro, Brazil (Diptera: Ceratopogonidae), Zootaxa 3566, pp. 39-50 : 40-41

Atrichopogon dactilus Felippe-Bauer , sp.nov.

Figs.1–14

Diagnosis. Male: Only extant species of Atrichopogon in the Neotropical region with pigmented wings and the posterior margin of the tergite 9 with an elongate and setose finger-like process that greatly surpassing the apex of gonocoxite. Female: Only extant species of Atrichopogon in the Neotropical region with a moderately wing length (1.19 mm), uniform color pattern of the antenna and legs, one large ovoid strongly sclerotized spermatheca (130 µm) and abdominal segments 1–7 pale, with ventrolateral black marks on segments 1–6 and the remainder of the abdomen brown.

Male. Head: Pale brown. Head width/mouthpart length 1.8–2.5 (2.1, n=10). Ommatidia with interfacet pubescence; broadly abutting medially for length of 3.6–4.5 (n=7) ommatidia ( Fig. 4 ). Antenna pale brown; proportions of 13 flagellomeres as in figure 3; flagellomeres 2–10 fused; plume on flagellomeres 1–9 welldeveloped; flagellomeres 10–13 without plume setae; flagellomere 9 = 0.72–0.9 (0.81, n=9) x shorter than flagellomere 10; flagellomere 13 with apical projection not basally constricted; AR 0.78–0.88 (0.84, n=7). Palpus ( Fig. 5 ) pale brown; third segment short, swollen at midlength, with well-developed deep pit on midlength; segment 4, 5 broadly fused; PR 1.8–2.1 (2.0, n=2).

Thorax ( Fig. 8 ): Dark brown. Scutum with setae arising directly from surface; with lateral suture. Paratergite with one seta. Wing ( Fig. 1 ) with patch of pigmentation in area of r-m and posterior to apex of R3; macrotrichiae in apical portion of r3 and m 1 in some specimens; wing length 1.08–1.12 (1.10, n=10) mm; CR 0.67–0.72 (0.69, n=10). Halter stem pale brown, capitate portion pale. Legs ( Fig. 6 ) yellowish brown, coxae, trochanters and basal portion of femora lighter; hind tibial spur longer than width of hind tibia; empodia present.

Abdomen ( Fig. 7 ): Segments 1–8 yellowish brown, with ventrolateral black marks on segments 1–3, 5–6; segment 9, 10 dark brown. Terminalia brown ( Fig. 9 ): segment 9 equal in width to segment 8; tergite 9 elongate, greatly surpassing apex of gonocoxite; posterior margin with long setose finger-like process, 0.30 length of tergite 9. Sternite 9 with ventral surface broadly convex, posterior margin concave, with transverse row of 7–12 long thin setae. Gonocoxite 2.7–3.2 (3.0, n=10) times as basal width, without medial lobe, gonocoxal apodeme beak-shaped. Gonostylus double, split to base, with inner portion elongate, curved basal process; basal ¼ of outer portion with patch of well developed bristles. Aedeagal-parameral complex with delicate lateral arms curved posteriorly; elongate, tapering from base, median portion a speculate lateral expansion; apical portion with mesal fringed excavation with two slender, pointed processes. Cercus short, bearing pointed apical process, ventral to tergite 9 at base of finger-like process.

Female. Similar to male, with following differences. Head: Head width/mouthpart length 1.6–1.8 (1.7, n=11); eyes broadly abutting medially for length of 4.1–4.5 (n=11) ommatidia ( Fig. 11 ). Antenna ( Fig. 10 ) pale brown, flagellomeres 1–8 elongate, vasiform, AR 1.34–1.44 (1.40, n=8). Mandible well developed with 14 teeth. Palpus ( Fig. 12 ) pale brown, moderately elongate, pit at midlength, segments 4, 5 partially fused in some specimens, PR 2.0–2.5 (2.2, n=5). Legs as in figure 13. Wing ( Fig. 2 ) pattern of pigmented membrane as for male; macrotrichia on membrane in apical portion of r3, m1 and in apical ½ of M1; wing length 1.15– 1.22 (1.19, n=11) mm. CR 0.68–0.73 (0.69, n=11). Abdomen ( Fig. 14 ): Segments 1–7 pale, with ventrolateral black marks on segments 1–6, well developed on segments 1–3, 5–6, smaller on segment 4; segments 8–10 brown; cercus pale brown. Genitalia: one dark brown ovoid spermatheca, with very short neck, measuring 115–145 (130, n=11) x 80 –90 (85, n=11) µm. Types. Holotype male, on microscope slide labeled “Sumidouro, Rio de Janeiro, BRASIL, 24–25.XI.2009, CDC light trap, São Caetano’s Rock cave, J.R.C. Alves col” (CCER). Allotype female, same data as holotype except 25–26.XI.2009, “forest area” (CCER). Paratypes 9 males, 10 females as follows: 5 males, 3 females same data as allotype (CCER; 1 male, 1 female MLP); 1 male same data as holotype (CCER); 2 females same data as holotype except “forest area” (CCER); 2 males, 3 females same data as allotype except “São Caetano’s Rock cave”, “forest area near São Caetano’s Rock” (CCER); 1 male, 2 females same data as allotype, except 2009 (CCER).

Etymology. The specific epithet is from the Greek: dactilus = finger, referring the figer-shaped projection on the posterior margin of tergite 9 of males of this species.

Taxonomic discussion. The male of Atrichopogon dactilus can be distinguished from the others Neotropical species with distinctively pigmented wings by the peculiar form of the posterior margin of the tergite 9 with its setose finger process that greatly extends beyond the apex of the gonocoxite. The female of the new species differ from A. nebulosus and A. nubeculosus described by Macfie (1939, 1949) and otherwise known only from a single females, by the smaller length of the wing 1.15–1.22 mm (about 1.5 mm in A. nebulosus ; about 1.3 mm in A. nubeculosus ), by the uniformly pattern of the legs and the strongly sclerotized spermatheca (tarsus darker than legs; spermatheca lightly sclerotized in A. nubeculosus ) and by the uniformly pale brown antenna (flagellomeres 9–13 darker than the flagellomeres 1–8 in A. nebulosus ).

Figures

FIGURE 9. Terminalia of Atrichopogon dactilus sp. nov., ventral view. Aedeagal-parameral complex and gonostylus in dissected view. Scale bar: 0.1 mm.

FIGURES 1 – 2. Wing photographs of Atrichopogon dactilus sp. nov. 1. male; 2. female.

FIGURES 3 – 8. Atrichopogon dactilus sp. nov., male. 3. Head, anterior view; 4. Eye separation, anterior view; 5. Palpus, lateral view; 6. Legs (left to right) of hind, mid- and forelegs, lateral view; 7. Abdomen, ventral view; 8. Scutum, lateral view.

FIGURES 10 – 14. Atrichopogon dactilus sp. nov., female. 10. Antenna; 11. Eye separation, anterior view; 12. Palpus, lateral view; 13. Legs (left to right) of hind, mid- and forelegs, lateral view; 14. Abdomen, ventral view.