Atrichopogon (Atrichopogon) eucnemus Macfie

Marino, Pablo I., Rossi, Juan F. & Cazorla, Carla G., 2022, A new species of Atrichopogon (Atrichopogon) Kieffer (Diptera: Ceratopogonidae) redescription and first record from Argentina of Atrichopogon (A.) eucnemus and Atrichopogon (A.) woodfordi by Macfie, Zootaxa 5188 (6), pp. 574-586 : 575-576

Atrichopogon (Atrichopogon) eucnemus Macfie

( Figs. 1–9 )

Atrichopogon eucnemus Macfie, 1939: 185 (male, female; Brazil); Borkent & Dominiak, 2020: 60 (in World catalog).

Atrichopogon (Atrichopogon) eucnemus: Borkent & Spinelli, 2007: 45 (in Neotropical catalog), Santarem & Felippe-Bauer, 2022: 39 (in Brazilian catalog).

Diagnosis. Only extant species of Atrichopogon in the Neotropical Region without pigmented wings, with male genitalia light brown except gonostylus brown; aedeagal-parameral complex moderately elongate, dorsal portion with bulbous projection, ventral portion stout, quadrangular with triangular medial projection. Female: scutum dark brown with humeral areas and prescutellar depression yellowish, scutellum yellowish; one dark brown, heavily sclerotized spermatheca with hyaline punctations and a short, broad neck.

Male. Head ( Fig. 1 ). Dark brown. Ommatidia with interfacetal spicules, nearly abutting medially for length of 3 ommatidia. Antenna brown with plume setae moderately well developed on flagellomeres 1–9, 2–5 fused, flagellomere 9–10 with plume setae, 11–13 elongated, 10 slightly longer than 1–9; flagellomere 13 with apical nipple not basally constricted; AR 0.86. Maxillary palpus ( Fig. 2 ) yellowish brown, segment 3 slender, with deep sensory pit opening beyond mid-length; segments 4–5 separate; segment 5 apically rounded; PR 2.30. Proboscis short, head width/ mouthparts length 1.65. Thorax. Dark brown except scutellum brown. Scutum with setae arising directly from surface, not in pits; with lateral suture. Paratergite with one stout seta. Anepisternum well developed, slightly bilobed posteriorly. Legs uniformly pale brown; hind tibia slightly expanded at apex; hind tibial spur thick, longer than width of hind tibia at midlength; hind tibial comb with 7–8 spines; prothoracic TR 3.00, mesothoracic TR 2.50, metathoracic TR 1.68; claws curved, tip bifid; empodia present. Wing ( Fig. 3 ) plain; without macrotrichiae on membrane; radial cells well developed, second 3X longer than first; wing length 0.92 mm; width 0.32 mm; CR 0.67. Halter pale. Abdomen. Tergites brown. Genitalia ( Fig. 4 ) light brown except gonostylus brown; segment 9 about equal in width to segment 8. Tergite 9 short, not extending to apex of gonocoxites, posterior margin somewhat rounded; sternite 9 narrow, posterior margin concave with one row of 6 setae. Gonocoxite moderately narrow without medial lobe, 2.4X longer than greatest breadth. Gonostylus 0.85 length of gonocoxite, curved, apex sharply pointed. Aedeagal-parameral complex moderately elongate, dorsal portion with bulbous projection; ventral portion stout, quadrangular with short, triangular medial projection; lateral arms stout, apically recurved 120º, directed posterolaterally, basal arch extending to 0.5 of total length. Cercus somewhat elongate extending beyond margin of tergite 9.

Female. Similar to male, with the following sexual differences: flagellomeres 1–8 vasiform, longer than broad, 9–13 greatly elongate ( Fig. 5 ), AR 1.56–1.70 (1.62, n = 4). Maxillary palpus ( Fig. 6 ) with segment 3 slender, with deep sensory pit opening beyond mid-length; segments 4-5 separate, their combined length longer than segment 3; PR 2.30–2.70 (2.52, n = 4); head width/ mouthparts length 1.24–1.53 (1.34, n = 4). Mandible poorly developed, without teeth.Thorax. Scutum ( Fig. 7 ) dark brown with humeral areas and prescutellar depression yellowish, scutellum yellowish. Legs uniformly brown; prothoracic TR 2.70–2.91 (2.78, n = 4), mesothoracic TR 2.45–2.64 (2.56, n = 4), metathoracic TR 1.65–1.80 (1.71, n = 4); claws curved, without bifid tips. Wing ( Fig. 8 ) membrane with abundant macrotrichiae on r 3, m 1; scarce on m 2;radial cells well developed, second cell 3X longer than first; wing length 1.00– 1.24 (1.14, n = 4) mm; width 0.44–0.50 (0.46, n = 4) mm; CR 0.65-0.68 (0.66, n = 4). Abdomen ( Fig. 9 ) yellowish. Tergites uniformly brown. Sternite 7 elongate, rectangular. Sternite 8 narrow, without elongate, cuticular extensions. Sternite 9 subquadrangular. Genital sclerotization closed, anterior margin rounded. Spermatheca globular, heavily sclerotized with minute hyaline punctations; measuring 76–90 (81, n = 4) by 64–90 (74, n = 4) µm, with short broad neck measuring 7.5 µm (n = 4). Cercus slender.

Distribution and bionomics. Atrichopogon eucnemus is previously known from Brazil. This is the first record from Argentina, where it was found in three natural protected areas on the coast of the Río de La Plata estuary: the Reserva Costera Municipal de Avellaneda, exclusively in the vineyards, the Reserva Natural provincial estancia San Juan, Parque Pereyra Iraola Iraola, and in the marginal forest within the Reserva Natural Integral Punta Lara. Specimens were collected with a sweep net during late afternoon, and with CDC light trap.

Type material. Holotype male, allotype female, Brazil, Santa Catarina, Nova Teutonia , 5-XI-1936, F. Plaumann ( BMNH, examined).

Other specimens examined. Argentina, Buenos Aires, Reserva Costera Municipal de Avellaneda (viñedos), 4-V-2021, 1 male, 1 female , J. Rossi, sweep net ( MLPA); same data except 23-III-2021, 1 female ; Buenos Aires, Reserva Natural Integral Punta Lara 34º 47’ 18” S; 58º 00’ 01” W, marginal forest, 9/ 10-XI-2014, 2 females , CazorlaCampos, CDC light trap. Buenos Aires, Reserva Natural provincial estancia San Juan, Parque Provincial Pereyra Iraola, 22-IV/ 1-V-2022, 1 male , Cazorla, CDC light trap.

Taxonomic discussion. This species is similar to A. (A.) woodfordi Macfie (1938) and A. (A.) comechingon Spinelli & Marino (2007) . The male genitalia of A. comechingon can be distinguished by the slender triangular process with blunt tip of the aedeagal parameral complex, and the cercus do not extend beyond tergite 9. The male genitalia of A. woodfordi differ from this species by its higher basal arch, the nearly straight posterior margin of sternite 9, and the moderately elongate tergite 9 that extends to about the level of the apex of gonocoxite. In addition, the males of these species do not have the distal 5 flagellomeres elongate. The female of A. eucnemus shares with females of A. comechingon and A. woodfordi a distinctive pattern of pigmentation on the scutum. The latter two species differ by the presence of some macrotrichiae in cell cua 1. Moreover, the genital sclerotization of A. comechingon is open and subquadrangular, and the neck of the spermatheca of A. woodfordi is distinctly paler.

Figures

FIGURES 1–4. Atrichopogon eucnemus Macfie. Male, 1–4. 1 head. 2 maxillary palpus. 3 wing. 4 genitalia. Scale bars: 0.1 mm.

FIGURES 5–9. Atrichopogon eucnemus Macfie. Female, 5–9. 5 head. 6 maxillary palpus. 7 scutum and scutellum. 8 wing. 9 tip of abdomen, ventral view. Scale bars: 0.1 mm.