The identity of Psilochironomus Sublette, 1966 (Chironomidae, Chironominae, Pseudochironomini) Author Andersen, Trond University of Bergen, University Museum of Bergen, Department of Natural History; P. O. Box 7800, NO- 5020 Bergen, Norway. Author Sanz-Laparra, Annui Malla University of Bergen, University Museum of Bergen, Department of Natural History; P. O. Box 7800, NO- 5020 Bergen, Norway. Author Giłka, Wojciech University of Gdańsk, Faculty of Biology, Department of Invertebrate Zoology and Parasitology, Laboratory of Systematic Zoology; Wita Stwosza 59, 80 - 308 Gdańsk, Poland. text Zootaxa 2024 2024-08-16 5496 1 111 118 http://dx.doi.org/10.11646/zootaxa.5496.1.6 journal article 10.11646/zootaxa.5496.1.6 1175-5326 13331113 B6EF5CA8-D3E0-4450-A1E0-23E39171F2BB 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. FIGURE 1. The four slides of male Psilochironomus fumeus (Walley in Curran, 1934 ) from Pára State, Brazil, housed in the Zoologische Staatssammlung in München (ZSM). FIGURE 2. Psilochironomus fumeus (Walley in Curran, 1934 ), male. A—Wing; B—Eye extension; C—Palp; D—Connection between second and third palpomere; E—Spur on fore tibia; F—Spur on mid tibia. TABLE 1. Lengths (in µm) and proportions of legs of Psilochironomus fumeus (Walley in Curran, 1934 ), male.

p 1	p 2	p 3
fe	1298–1339, 1324	1421–1524, 1457	1401–1483, 1442
ti	1730–1792, 1756	1607–1710, 1648	1916–1936, 1921
ta 1	1524–1607	721–762, 747	803–845, 824
ta 2	515–556	330–371, 350	391–433, 412
ta 3	494–515	278–299, 288	309–330, 324
ta 4	453–474	155–175, 164	144–165, 159
ta 5	227–247	82–103, 88	82–113, 93
LR	0.871–0.905	0.443–0.463, 0.454	0.426–0.430, 0.429
BV	2.644–2.744	4.279–4.357, 4.324	4.102–4.489, 4.240
SV	1.949–2.014	4.054–4.257, 4.159	4.025–4.150, 4.081
BR	1.52–1.84	1.67–1.86, 1.73	1.92–2.31, 2.12

FIGURE 3. Psilochironomus fumeus (Walley in Curran, 1934 ), male. A—Hypopygium, dorsal view; B—Hypopygium with tergite IX and anal point removed, dorsal view; C—Anal point, gonocoxite and gonostylus, lateral view; D—Gonocoxite, gonostylus and inferior volsella, ventral view; E—Superior volsella, dorsal view; F—Inferior volsella, dorsal view. 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.