Psilochironomus fumeus
Creators: name: Andersen, Trond
name: Sanz-Laparra, Annui Malla
name: Giłka, Wojciech
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Chironomidae
Psilochironomus
Psilochironomus fumeus

description: Psilochironomus fumeus (Walley in Curran, 1934)
(Figs 1–3)
Material examined. Three adult males, BRAZIL, Pará State, Rio Paru do Oeste, Mission Tiriyó, 2º13’54’’N 55º57’39’’W, 26.03– 21.04.1962, leg. E.J. Fittkau (A361-3, A361-6, A361-10) (ZSM); one adult male, Brazil, Pará State, Rio Paru do Oeste, Maloca Apico, 20.04.1962, leg. E.J. Fittkau (A 366-1) (ZSM) (Fig. 1).
Redescription. Adult male (n = 1–4)
Body size and proportions. Total length 5.79–6.16, 5.98 mm. Wing length 2.62–2.68, 2.64 mm. Total length / wing length 2.16–2.28, 2.22. Wing length / length of profemur 1.97–2.06, 2.00.
Colouration. Head, thorax and abdomen dark brown, legs with femur and tibia brown, tarsi slightly lighter brown. Wing with broad, dark band in median 1/3.
Antenna. AR 2.53–2.71, 2.60. Terminal flagellomere 1112–1148, 1129 µm long.
Head. Temporal setae 25–28, partly bi- to tri-serial near transition of eye to its dorsomedial extension. Eye extension nearly parallel-sided, about twice as wide as high, with 5–6 facets per diagonal (Fig. 2B). Clypeus with 48–59 setae. Tentorium 442–480 µm long, 100–108 µm wide. Stipes 296 µm long, 20 µm wide. Palpomere lengths / median width (in µm): 68–80 / 51–60, 80–92 / 60–64, 288–294 / 64–72, 296–320 / 52–56, 360–408 / 35–36. Second palpomere rounded, connect to ventrolateral surface subproximally on third palpomere at an angle of up to 90 ° (Figs 2C, D). Third palpomere slightly swollen proximally, equipped with cluster of 8–12 strong, spine-like setae proximomedially, 62–71 µm long. Third to fifth palpomeres with rows of comparatively short, erect setae mesally; third palpomere apparently lacking sensilla clavata subapically.
Thorax. Antepronotum broad, collar-like, with 6–7 ventrolateral setae. Acrostichals short, decumbent, arising from small, pale spots, apparently 25–30 in partly double row occurring from near antepronotum to mid scutum; dorsocentrals 8–11 in single row; prealars 4–7, supraalar 1. Scutellum with 16–21 setae in single to partly double row.
Wing (Fig. 2A). VR 1.04–1.10, 1.07. Costa not or only barely extended. Brachiolum with 1 seta; R with 20–26, 22 setae; R 1 with 0–4, 1 seta; R 4+5 with 1–2 seta apically; other veins bare. Squama with 9–16, 12 setae.
Legs. Spur of fore tibia (Fig, 2E) 69–73, 71 µm long; spurs of mid tibia (Fig. 2F) 65–73 µm and 72–83 µm long; spurs of hind tibia 73–77 µm and 83–90 µm long. Width at apex of fore tibia 76–83, 80 µm; of mid tibia 90–105 µm; of hind tibia 92–107 µm. Lengths and proportions of legs as in Table 1.
Hypopygium (Fig. 3A–F). Tergite IX with about 20 weak setae; laterosternite IX with 6 setae. In dorsal view anal point broadly subtriangular with rounded apex, 78 µm long, 75 µm wide at base; in lateral view with apex hooked ventrad. Phallapodeme 159 µm long. Transverse sternapodeme narrow, arched, with low, rounded oral projections, 102 µm long. Gonocoxite 268 µm long. Superior volsella straight, projecting caudally, 100 µm long, 28 µm wide medially, with microtrichia and about 12 setae medially, apical part bare, 25 µm long, tapering, with hooked apex. Inferior volsella ovate, 124 µm long, 62 µm wide medially, with microtrichia and about 18 strong marginal and dorsal setae. Gonostylus stout with bluntly rounded apex, 212 µm long. HR 1.34. HV 2.91.
description: Published as part of Andersen, Trond, Sanz-Laparra, Annui Malla & Giłka, Wojciech, 2024, The identity of Psilochironomus Sublette, 1966 (Chironomidae, Chironominae, Pseudochironomini), pp. 111-118 in Zootaxa 5496 (1) on pages 113-116, DOI: 10.11646/zootaxa.5496.1.6, http://zenodo.org/record/13331113