Atrichopogon (Atrichopogon) trochantispina Rossi, Marino & Spinelli 2025, n. sp.
Creators: name: Rossi, Juan Francisco
name: Spinelli, Gustavo Ricardo
name: Hochman, Sabrina Ivanne
name: Marino, Pablo Ignacio
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Ceratopogonidae
Atrichopogon
Atrichopogon trochantispina

description: Atrichopogon(Atrichopogon)trochantispina
Rossi, Marino & Spinelli, n. sp.
(Figs 3; 4; 8B; 9B)
urn:lsid:zoobank.org:act: 48DE212B-192E-4A76-89D1-793B74962D9A
TYPE MATERIAL. — Holotype. Peru • ♂; Cuzco, Kirigueti; VII.2004, J. Williams; light trap; MLPA.
Allotype. Peru • ♀; same data as for holotype; MLPA.
Paratype. Peru • 1 ♀; same data as for holotype; MLPA.
ETYMOLOGY. — The name trochantispina (spine) refers to the distinctive spines on the trochanter of hind leg.
DISTRIBUTION. — Atrichopogon trochantispina Rossi, Marino & Spinelli, n. sp. is known only from the type locality in Kirigueti (11°38’13”S, 73°07’07”W), at an elevation of 395 m.
DIAGNOSIS. — Only extant species of Atrichopogon in the New World with pigmented wings and the trochanter of hind leg bearing black spines.
DESCRIPTION
Male adult (Figs 3; 8B)
Head (Fig. 3A). Golden brown. Ommatidia (Fig. 3B) with interfacet spicules, abutting medially for length of 3-4 ommatidia. Antenna pale brown with plume setae well developed, flagellomeres 2-10 fused, flagellomere 9 with plume setae, flagellomere 10 without plume setae, 11-13 elongated, 10 slightly longer than 1-9; flagellomere 13 with apical nipple, not basally constricted; AR 0.96. Maxillary palpus (Fig. 3C) pale brown with third segment moderately elongate, swollen at midlength, with deep sensory pit opening just beyond midlength; segments 4, 5 closely apressed; segment 5 conical; PR 2.56. Proboscis short, head width/mouthparts length 2.8.
Thorax (Fig. 3E). Dark brown with small pale patch on humeral areas, ventral portion of pleurae lighter. Scutum with setae arising directly from surface, not in pits; with lateral suture. Paratergite with one stout seta. Anepisternum well developed, broadly bilobed posteriorly. Legs uniformly yellowish brown; hind trochanter with two black spines, the anterior one stouter; hind tibia slightly expanded at apex; hind tibial spur thick, length longer than width of hind tibia at midlength; hind tibial comb with nine spines; prothoracic TR 3.71, mesothoracic TR 3.57, metathoracic TR 3.00; claws curved, bifid at tip; empodia present. Wing (Fig. 3D) with two distinct dark patches in area of r-m and in r 3 posterior to apex of R 3; with macrotrichiae in apical portion of r 3, m 1; both radial cells well formed, second nearly five × longer than first; wing length 0.92 mm; width 0.32 mm; CR 0.67. Halter pale.
Abdomen (Fig. 3F). Tergites 1-6 light brown with dark lateral patches, 7-8 entirely light brown, genitalia dark brown. Genitalia (Figs 3G; 8B) large, segment 9 about equal in width to segment 8. Tergite 9 narrow, short, not extending to apex of gonocoxites, tapering distally, posterior margin somewhat rounded with 6 black, long setae, 4 medial stout, 2 lateral ones thinner; sternite 9 narrow, with narrow longitudinal wrinkle (probably due to slide mounting process), posterior margin protruding with 2 pairs of mesal setae, each pair contiguous to wrinkle. Gonocoxite moderately stout, without medial lobe, 2.2 × longer than greatest breadth. Gonostylus 0.7 length of gonocoxite, split from midportion to apex (0.4 distal), outer portion nearly straight with one stout seta; inner portion slightly shorter, curved, apex pointed. Aedeagal-parameral complex elongate; dorsal portion with V-shaped basal arch, mesolateral margins subparallel, greatly expanded distally, hyaline, with broad, convex apex, pair of slender, sclerotized, subparallel, inner prongs ending in an arrow-shaped process, contiguous with a feet-shaped process directed laterally; ventral portion stout, triangular, lateral arms stout, recurved, directed posterolaterally, posterolateral margins slightly sinuate, apex not well discernible, apparently bulbous, produced beyond tergite by a short distance. Cercus elongate, broad basally, apex rounded, extending beyond margin of tergite 9.
Female adult (Figs 4; 9B)
Head. As for male, with following differences: flagellum brown, proportions of flagellomeres as shown in Figure 4A; flagellomeres 1-8 longer than broad, vasiform, flagellomeres 9-13 elongated; AR 1.46-1.48 (1.47, n=2). Maxillary palpus (Fig. 4B) with third segment slender, with deep sensory pit opening near midlength; segments 4, 5 separate, their combined length slightly longer than third segment; PR 2.20 (n = 2); head width/mouthparts length 2.15-2.39 (2.27, n=2). Mandible with 21 teeth.
Thorax. Scutum dark brown with humeral areas yellowish. Legs uniformly yellowish brown; prothoracic TR 3.71 (n=2), mesothoracic TR 3.25-3.50 (3.38, n=2), metathoracic TR 2.80-3.00 (2.90, n=2); claws curved, not bifid at tip. Wing (Fig. 4C) with the same pattern of pigmented membrane, with abundant macrotrichiae on r 3, m 1; radial cells narrow, second five × longer than first; wing length 0.92-0.98 (0.95, n=2) mm; width 0.36-0.38 (0.37, n=2) mm; CR 0.65 (n=2).
Abdomen (Fig. 4D).Tergites 1-6 pale brown with dark lateral patches, 7-8 lighter, 9 dark brown, 10 uniformly light brown. Sternite 7 rectangular. Sternite 8 without elongate, cuticular extensions, posterior margin with narrow, mesal projection. Sternite 9 (Fig. 4E; 9B) subquadrangular. One spermatheca (Fig. 4F; 9B) large, ovoid with short, stout neck, sclerotized, measuring 0.120 -0.124 (0.122, n=2) by 0.098 -0.104 (0.100, n=2) mm. Cercus yellowish brown.
REMARKS
Of the Neotropical species with distinctive pigmented wings, Atrichopogon trochantispina Rossi, Marino & Spinelli, n. sp. is the only one bearing stout black spines on the hind trochanter, likely an autapomorphy of this species. The presence of splitted gonostylus near midlength is shared with Atrichopogon maculipennis Clastrier, 1968 from French Guiana, Atrichopogon nukini Felippe-Bauer, 2018 and Atrichopogon riopardensis Farias, Pessoa & Paulino-Rosa, 2021 from Brazil. The wing of A. maculipennis has the distal 1/3 entirely dark and the gonostylus is shorter and thicker with the projections broadly separated. The dark spots of the wings of A. nukini and A. riopardensis are similar to the new species, however, the tergite 9 of A. nukini is moderately long, extending about the level of apex of gonocoxite, and the inner portion of the gonostylus of A. riopardensis is four times shorter than the outer portion.
Atrichopogon clastrieri Spinelli & Marino, 2007 from Argentina is also similar to this new species, but in males of A. clastrieri the posterior margin of the tergite 9 bears a small medial lobe, and the gonostylus is simple, among other genital differences. The female mandible of A. clastrieri is poorly developed, without teeth.
description: Published as part of Rossi, Juan Francisco, Spinelli, Gustavo Ricardo, Hochman, Sabrina Ivanne & Marino, Pablo Ignacio, 2025, Four new species of Atrichopogon Kieffer, 1906 (Diptera, Ceratopogonidae) from Peruvian Amazonia and a key of Neotropical species of this genus with pigmented wings, pp. 185-202 in Zoosystema 47 (13) on pages 190-193, DOI: 10.5252/zoosystema2025v47a13, http://zenodo.org/record/15308695