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Family: Chironomidae Newman, 1834 Subfamily: Chironominae Newman, 1834 Tribe: Tanytarsini Zavřel, 1917 Genus: Tanytarsus van der Wulp, 1874, Published as part of Giłka, Wojciech, Paasivirta, Lauri, Gadawski, Piotr & Grabowski, Michał, 2018, Morphology and molecules say: Tanytarsus latens, sp. nov. from Finland (Diptera: Chironomidae), pp. 569-579 in Zootaxa 4471 (3) on page 571, DOI: 10.11646/zootaxa.4471.3.8, http://zenodo.org/record/1439962

Tanytarsus latens sp. nov. Type material. Holotype (DIZUG), adult male specimen (excl. thorax) slide-mounted in Canada balsam: FINLAND, OSTROBOTHNIA BOREALIS, Palokkaanlampi and Rumajärvi ca. 40 km W of Rovaniemi (66°26'N 24°56'E), 7–28 August 2017, Malaise trap, J. Salmela. Paratypes: sampling data as holotype: 1 male (excl. thorax) in Canada balsam, 5 males + 1 hypopygium in Euparal (DIZUG); SATAKUNTA, Kauklastenjärvi ca. 15 km SE of Rauma (61°04'N 21°46'E), 17 August 2010, 1 male (in Euparal), hand net, L. Paasivirta (LP). DNA voucher: DNA extracted from thorax tissue in elution buffer (MIZ PAS). Derivatio nominis. From the Latin adjective meaning concealed or disguised by others. Diagnosis. Darkly coloured, relatively big [wing length: 2245–2540 (2430) µm]. Frontal tubercles small, 2–12 µm long at most. Anal tergite bands of H-type, with broad median connection. Anal point slender, with narrowly rounded apex and 2–3 spinulae. Superior volsella rounded at base, elongate, tapering towards tip, usually with apical nose curved medially. Stem of median volsella straight, slightly swollen in distal half, with irregularly arranged subulate lamellae. Description. Adult male (n = 8 + 1 male hypopygium). Colouration (in alcohol). Eyes black. Antenna, tentorium, scutal stripes, scutellum, postnotum, sternum, hypopygial apodemes and proximal leg segments, incl. femora and tibiae dark brown to black. Head capsule, mouthparts, ground colour of thorax, tarsi and abdomen brown with slight olive undertone. Wing and haltere pale brownish. Head. Eyes reniform, with dorsomedian extension gradually narrowing from 5 facets at base to 4: 4: 3/2 facets medially. Antenna with 13 distinct flagellomeres, AR 1.53–1.78 (1.66), plume fully-developed. Frontal tubercles minute, usually in shape of tiny swellings (2–3 µm), rarely conical or cylindrical, 12 µm long at most (Fig. 1A, B). Lengths of palpomeres 2–5 (in µm): 60–72 (63), 155–183 (172), 143–163 (156), 198–258 (244); pm3 always longer than pm4. Clypeus with 17–24 setae. Thorax chaetotaxy (n = 5). Ac 20–22, biserial, with several setae arranged in small field near antepronotum; Dc 11–14 on each side; Pa 1–2 on each side; Scts 4–8, usually 8. Wing (Fig. 1C). Length 2245–2540 (2430) µm. Venation pattern and chaetotaxy typical of the genus, as shown in Fig 1C; VR Cu 1.14–1.16 (n = 2). Legs. Fore leg tibia with slightly curved distally spur 25–30 µm long. Mid and hind leg tibiae with combs separated, each comb bearing spur; spurs straight or slightly curved, 28–36 µm long on mid leg and 40–55 µm long on hind leg. Basitarsus of mid leg with 4–7 sensilla chaetica. Lengths of leg segments and leg ratios as shown in Table 1. Hypopygium (Figs 2, 3). Gonostylus 160–180 µm, longer than gonocoxite. Anal tergite bands of H-type, with broad median connection (Fig. 2A). Anal tergite usually with 2 long median setae, rarely 3 setae present (n = 2) or median setae absent (n = 1); extensive microtrichia-free area surrounding posterior sections of anal tergite bands; lateral teeth and lateral setae absent; shoulders on posterior margin weak (Figs 2A, 3A). Anal point slender, evenly tapering towards narrowly rounded apex, bearing 2–3 well-developed spinulae placed between crests (Figs 2A, 3A). Superior volsella rounded at base, elongate, tapering towards narrow tip, usually with apical nose curved medially, 4–6 dorsal setae and 3 setae on anteromedian margin (proximal seta weaker), microtrichia absent; digitus long, but not extending beyond margin of superior volsella, pointed (Figs 2, 3B). Stem of median volsella 40–45 µm long, straight, slightly swollen in distal half, bearing several setiform and subulate, irregularly arranged lamellae (Fig 2B). Inferior volsella straight, stout, with distal part swollen, roundish, bearing numerous strong setae (Figs 2A, B).

Cladotanytarsus (Cladotanytarsus) saetheri, sp. nov. Figs 1A, B; 2; 3A–E; 4A; 5A–D Type material. Holotype, adult male: NORWAY, FINNMARK: Helsegård near Karasjok (69°26'13"N / 25°41'01"E), 3 August 2003, swarms near river, sweep net, W. Giłka. Paratypes. 47 males as holotype; FINLAND, OSTROBOTHNIA KAJANENSIS: Oulujärvi-Paltaniemi, 12 June 2017, netting water surface, 3 males, L. Paasivirta; RUSSIA, FAR EAST: Amur obl., Sigikta River below bridge of the road Neryungri–Never, 3 August 2006, 1 male, T.M. Tiunova; Magadan obl., Taui River, 26 July 2002, 1 male, E. Khamenkova; Primorsky Krai, Ussuri River near bridge of the highway Vladivostok – Khabarovsk, 4 August 2003, 1 male, O.V. Orel. CANADA, MANITOBA: Lake Winnipeg: Beaver Creek, 8 June 1971, emergence trap, 2 males, 24 June 1971, emergence trap, 1 male, 22 July 1971, emergence trap, 1 male, 28 July 1971, emergence trap, 1 male, 29 July 1971, emergence trap, 1 male, E. Johnson, M.P. McLean et al.; Gull Harbour, 16 July 1969, light trap, 1 male, P.S.S. Chang; McCreary Island, 25 July 1969, light trap, 1 male, P.S.S. Chang; Victoria Beach, 9 July 1969, light trap, 2 males, P.S.S. Chang (prep. O.A. Saether); USA, COLORADO: Larimer Co., Cache La Poudre River, 15 km NW of Laporte, 26 August 1968, 1 male, F.G. Andrews; Pueblo Co., Arkansas River / Pueblo Reservoir at: Hobson Ranch, 19 September 1985, 2 males, Pueblo Boulevard Bridge, 15 August 1985, 1 male, Stilling Basin Bridge, 15 August 1985, 2 males, S.J. Herrmann; MICHIGAN: Newaygo Co., White River near Ramona, 21 May 1982, 2 males, P.C. Baumann & M. Clavla; SOUTH CAROLINA: Pickens Co., Clemson, Wildcat Creek, 31 March 1976, 1 male, P. Hudson; WISCONSIN: Burnett Co., 20 km E & 7 km S of Siren, 6 August 1966, 2 male hypopygia, D.C. Hansen. Derivatio nominis. The specific name is a patronym commemorating the Chironomidae taxonomist and ecologist, Ole Anton Saether (1936–2013). Diagnosis. Acrostichal setae sparse, placed on top of scutum. Wing vein M3+4 ending only slightly proximally of R4+5 or under R4+5. Phallapodeme strongly curved in anterior section. Anal point stocky, with large spinulae densely arranged between prominent crests. Superior volsella with well-developed apical lip and small field of microtrichia confined to dorsolateral surface at base; digitus evenly tapering toward blunt tip. Stem of median volsella strongly elongated, straight or slightly and evenly curved at most, bearing furcate lamellae on apex. Inferior volsella with dorsal lobe forming a nose. Description. Adult male (n = 73 specimens + 2 male hypopygia). Colouration (in alcohol). Eyes black. Antenna, tentorium, scutal stripes, scutellum, postnotum and sternum brown to dark brown. Head capsule, mouthparts, ground colour of thorax, legs and abdomen including hypopygium brown or light brown with greenish undertone. Wing and haltere pale brownish. Head. Eyes reniform, broadly separated by frons. Antenna with 13 distinct flagellomeres; plume fullydeveloped or weak, AR 0.69–0.92 (0.80, n = 18) in specimens with plume fully-developed or AR 0.54–0.67 (0.60, n = 3) in specimens with plume reduced. Frontal tubercles minute, usually in a form of tiny swellings, rarely conical, 8 µm long at most. Lengths of palpomeres 2–5 (in µm) in specimens with antennal plume fully-developed (n = 21): 32–44 (36), 72–100 (88), 79–120 (94), 123–172 (144); palps shorter in specimens with plume reduced (n = 3): 32–40 (36), 66–92 (77), 76–100 (88), 112; pm4> pm3 (n = 21) or pm4 ≤ pm3 (n = 3). Clypeus with 7–14 setae. Thorax chaetotaxy. Ac 2–6 placed on top of scutum; Dc 5–9 on each side; Pa 1–2 exceptionally 3 on each side (n = 1); Scts 2–4, rarely 6 (n = 2). Wing (Fig. 1A, B). Length 1195–1590 (1405) µm. Venation pattern and chaetotaxy slightly variable (also in specimens of the same sample). Veins ending as follows (in order from base to tip): R1, Cu1 (or Cu1 ending under R1), M2+3, M3+4, R4+5 (or M3+4 ending under R4+5), M1+2; VR Cu 1.22–1.43 (1.31). Macrotrichia on C, R, distal half of M1+2, rarely on R1, distal part of R4+5 and distal half of false vein above M3+4, other veins bare; membrane with macrotrichia on r4+5, sometimes in m1+2, exceptionally a couple of macrotrichia in m3+4 (n = 1), other cells bare. Legs. Fore leg tibia with slightly curved spur 15–24 (20) µm long. Combs of mid and hind leg tibiae separated, ca. twice shorter than spurs; spurs of mid and hind leg unequal in shape (one shorter and straight, second longer and curved) and length: 12–24 µm long on mid leg and 20–36 µm long on hind leg. Basitarsus of mid leg with 2–3 sensilla chaetica. Lengths of leg segments and leg ratios distinctly different in specimens with fully-developed and reduced antennal plume, as shown in Table 1. fe ti ta1 ta2 ta3 ta4 ta5 LR p1 465 – 660 265 – 385 550 – 735 295 – 385 220 – 310 150 – 220 85 – 110 1.81 – 2.30 (575) (325) (640) (345) (270) (185) (100) (1.98) 570 – 745 385 – 450 570 – 600 285 195 – 235 145 – 150 105 – 115 1.43 – 1.49 (645) (420) p2 545 – 690 435 – 565 220 – 330 135 – 195 100 – 180 65 – 115 55 – 85 0.50 – 0.62 (600) (500) (265) (155) (115) (80) (65) (0.53) 610 – 640 495 – 510 250 135 115 85 85 0.49 p3 550 – 780 525 – 765 355 – 460 235 – 295 205 – 240 130 – 165 85 – 105 0.56 – 0.65 (675) (660) (405) (260) (225) (150) (95) (0.61) 675-690 645 – 675 330 205 190 120 90 0.49 Hypopygium (Figs 2; 3A–E; 4A; 5A–D). Gonostylus shorter than gonocoxite, 70–100 (80) µm long, rarely longer, up to 120 µm (n = 3, Finnish specimens). Phallapodeme strongly curved in anterior section. Anal tergite with bands of V-type separated, bearing 1 lateral seta on each side and 3–15 (8) median setae arranged irregularly at base of anal point (Figs 2A). Anal point stocky, broad at base, tongue-shaped or lanceolate, tapering toward blunt tip or with short nipple-like apical elongation, bearing 6–13 relatively large spinulae (exceptionally 3 spinulae present, n = 1) densely arranged between prominent crests (Figs 2A, 3A–E). Superior volsella rounded at base, narrowed at mid length, usually slightly swollen distally, with well-developed apical lip, 4–11 (usually 6–7) dorsal setae and small field of microtrichia confined to dorsolateral surface at base; digitus protruding slightly beyond apex of superior volsella, evenly tapering toward blunt tip (Figs 2A, 4A). Stem of median volsella strongly elongated, 40–60 (55) µm long, straight or slightly and evenly curved at most, bearing several setiform and 5–7 rarely 8 furcate lamellae on apex (Figs 2A, B, 5A–D). Inferior volsella with slight knee-like extension at base and distinct dorsal lobe forming a nose at mid length of inferior volsella (Figs 2A, 4A). Remarks. Our studies on Cladotanytarsus, by now carried out independently as based on materials from North America (M.P., W.G.) and Fennoscandia (L.P., W.G.) indicated that the same unknown species may occur in both the regions studied. Further materials from the Russian Far East confirmed its wide Holarctic distribution. As a result, Cladotanytarsus saetheri is described and compared with its relative, C. gedanicus. These two species were previously misidentified (Giłka 2009) due to morphological similarities in the hypopygial structure, i.a. peculiar shape of the median volsellae consisted of a long stem bearing dense furcate lamellae on apex (cf. Giłka 2001: fig. 2). A detailed character analysis indicated several distinct differences between C. saetheri and C. gedanicus, as shown in Figures 1 & 3–5 and Table 2. Though the weakly plumose and abbreviated antennae, shortened palps and changed proportions of legs segments in several examined males of Cladotanytarsus saetheri may disrupt the species definition, these characters were found as a result of a limited flying ability in specimens collected from the water surface (material from Finland). Thus, they are treated separately in the above description; nevertheless, all the presently examined individuals are defined as conspecific. Interestingly, the Finnish specimens were not sampled by simultaneous netting from the air and vegetation. So, it is probable, that they were copulating on the water surface. Such nontypical mode of life may have a diverse background, being e.g. an adaptation to austere conditions, which in a longterm period may lead to behavioural and spatial isolation (e.g. Serra-Tosio 1974, Hermann et al. 1987, Giłka & Paasivirta 2009, Giłka et al. 2013). This phenomenon usually results in parallel morphological modifications of the wings, antennae, palps and legs, in some cases called as atrophied aberrant characters, and may occur in different Chironomidae groups, including the Tanytarsini (e.g. Saether 1971, Cranston 1980, Giłka 2011b). Some peculiar leg structures/characters in Tanytarsini, however, are recogniZed as distinct apomorphies (Giłka 2011b; ZakrZewska et al., in press). Cladotanytarsus saetheri seems to prefer large, slow flowing rivers and the open shores of large oligotrophic lakes., Published as part of Puchalski, Mateusz, Paasivirta, Lauri & Giłka, Wojciech, 2018, Cladotanytarsus saetheri sp. nov. and C. gedanicus Giłka: Holarctic sibling species (Diptera: Chironomidae), pp. 428-436 in Zootaxa 4394 (3) on pages 429-433, DOI: 10.11646/zootaxa.4394.3.8, http://zenodo.org/record/1199834, {"references":["Gilka, W. (2001) A reView Of POliSh Cladotanytarsus Kieffer (Diptera: ChirOnOmidae) with deScriptiOn Of three new SpecieS. Polish Journal of Entomology, 70, 307 - 328.","Gilka, W. & PaaSiVirta, L. (2009) EValuatiOn Of diagnOStic characterS Of the Tanytarsus chinyensis grOup (Diptera: ChirOnOmidae), with deScriptiOn Of a new SpecieS frOm Lapland. Zootaxa, 2197, 31 - 42.","Gilka, W., SOSzyNSka-Maj, A. & PaaSiVirta, L. (2013) The peculiar winter-actiVe midge, Diamesa starmachi (Diptera: ChirOnOmidae). Polish Journal of Entomology, 82, 201 - 211.","Gilka, W. (2011 b) Six unuSual Cladotanytarsus Kieffer: tOwardS a SyStematicS Of the genuS and reSurrectiOn Of Lenziella Kieffer (Diptera: ChirOnOmidae: TanytarSini). Zootaxa, 3100, 1 - 34."]}

Cladotanytarsus (Cladotanytarsus) gedanicus Giłka, 2001 Figs 1C, D; 3F–J; 4B; 5E–H Material examined. Holotype and paratypes (see Giłka 2001). EUROPE. FINLAND, LAPLAND: Čuonjáčohkka, small reservoir by roadside (Kittiläntie) 45 km SW of Inari (68°39'52"N / 26°18'35"E, 242 m a.s.l.), 6 August 2003, netting, 3 males, W. Giłka; Lemmenjoki-Njurgalahti (68°45'31"N / 26°14'03"E, 175 m a.s.l.), 20 July 2002, netting, 3 males, W. Giłka; Tuurujärvi near Kaamanen (69°09'30"N / 27°13'08"E, 142 m a.s.l.), 26 July 2003, netting, 2 males, W. Giłka; NORTHERN OSTROBOTHNIA: Olhava near Oulu, Gulf of Bothnia (65°27' 48"N / 25°22'21"E, 5 m a.s.l.), 13 July 2002, netting, 3 males, W. Giłka. Several sites on the coast of Bothnian Bay and Bothnian Sea in the beginning of June and in late July and early August 1968 –2012, L. Paasivirta (see also Paasivirta 2012). POLAND, SWEDEN: see Giłka 2009. NORTH AMERICA. CANADA, MANITOBA: Portage Creek, 20 September 1967, 1 male, W.M. Hominick; NUNAVUT: Chesterfield, 26 August 1950, 1 male, J.R. Vockeroth. USA, COLORADO: Pueblo Co., University of Southern Colorado campus, 25 September 1981, light trap, 1 male, J. Linam; NEW MEXICO: Mora Co., Charette Lake, 6 September 1974, Malaise trap, 42 males, M. Beard; San Juan Co., Morgan Lake, 1 July 1963, 1 male, L.A. McElfresh; San Miguel Co., Storrie Lake, 2 July 1970, light trap, 3 males, G. Harrell. Remarks. Cladotanytarsus gedanicus is now for the first time recorded from the Nearctic region, although its wide range in the Holarctic was previously indicated (Giłka 2011a). This species is distributed across North America, from Nunavut and Manitoba in the north through Colorado to New Mexico in the south. It has so far been reported from Europe (Poland, Finland, Sweden) and the Russian Far East (Makarchenko et al. 2005, Yavorskaya et al. 2017); however, the records from Asia require confirmation. The data on C. gedanicus from Norway by Giłka (2009) pertain to C. saetheri. For ecology and seasonal dynamics of C. gedanicus in Poland see Giłka (2001, 2002, 2009)., Published as part of Puchalski, Mateusz, Paasivirta, Lauri & Giłka, Wojciech, 2018, Cladotanytarsus saetheri sp. nov. and C. gedanicus Giłka: Holarctic sibling species (Diptera: Chironomidae), pp. 428-436 in Zootaxa 4394 (3) on page 433, DOI: 10.11646/zootaxa.4394.3.8, http://zenodo.org/record/1199834, {"references":["Gilka, W. (2001) A reView Of POliSh Cladotanytarsus Kieffer (Diptera: ChirOnOmidae) with deScriptiOn Of three new SpecieS. Polish Journal of Entomology, 70, 307 - 328.","Gilka, W. (2011 a) Ochotkowate-Chironomidae, plemie: Tanytarsini, postaci dorosle, samce. Klucze do oznaczania owadow Polski. [Non-biting midges-Chironomidae, tribe Tanytarsini, adult males. Keys for the Identification of Polish Insects]. No 177. Part XXVIII, Muchowki - Diptera. Issue 14 b. POlSkie TOwarzyStwO EntOmOlOgiczne, BiOlOgica SileSiae, WrOclaw, 95 pp. [in POliSh]","Gilka, W. (2002) TanytarSini (Diptera: ChirOnOmidae) Of POland - a fauniStic reView. Polish Journal of Entomology, 71, 415 - 428."]}

1. Metacommunity theory focuses on assembly patterns in ecological communities, originally exemplified through four different, yet non-exclusive, perspectives: patch dynamics, species sorting, source-sink dynamics, and neutral theory. More recently, three exclusive components have been proposed to describe a different metacommunity framework: habitat heterogeneity, species equivalence, and dispersal. Here, we aim at evaluating the insect metacommunity of a subarctic stream network under these two different frameworks. 2. We first modelled the presence/absence of 47 stream insects in northernmost Finland, using binomial generalised linear models (GLMs). The deviance explained by pure local environmental (E), spatial (S), and climatic variables (C) was then analysed across species using beta regression. In this comparative analysis, site occupancy, as well as taxonomic and biological trait vectors obtained from principal coordinate analysis, were used as predictor variables. 3. Single-species distributions were better explained by in-stream environmental and spatial factors than by climatic forcing, but in a highly variable fashion. This variability was difficult to relate to the taxonomic relatedness among species or their biological trait similarity. Site occupancy, however, was related to model performance of the binomial GLMs based on spatial effects: as populations are likely to be better connected for common species due to their near ubiquity, spatial factors may also explain better their distributions. 4. According to the classical four-perspective framework, the observation of both environmental and spatial effects suggests a role for either mass effects or species sorting constrained by dispersal limitation, or both. Taxonomic and biological traits, including the different dispersal capability of species, were scarcely important, which undermines the patch dynamics perspective, based on differences in dispersal ability between species. The highly variable performance of models makes the reliance on an entirely neutral framework unrealistic as well. According to the three-component framework, our results suggest that the stream insect metacommunity is shaped by the effect of habitat heterogeneity (supporting both species-sorting and mass effects), rather than species equivalence or dispersal limitation. 5. While the relative importance of the source-sink dynamics perspective or the species-sorting paradigm cannot be deciphered with the data at our disposal, we can conclude that habitat heterogeneity is an important driver shaping species distributions and insect assemblages in subarctic stream metacommunities. These results exemplify that the use of the three-component metacommunity framework may be more useful than the classical four perspective paradigm in analysing metacommunities. Our findings also provide support for conservation strategies based on the preservation of heterogeneous habitats in a metacommunity context.

Tanytarsus salmelai sp. n. (Figs 3, 4, 15–18, 21, 24, 27) Type material. Holotype male, slide mounted in Canada balsam: Finland, Arcto-Alpine ecoregion, Aksonjunni, 36 km south of Nuorgam, Utsjoki, 2 July 2007. Paratypes. 1 male: same data as holotype; 2 males: Finland, Northern boreal ecoregion, Vasanvuoma near Kittilä, 26 June 2007; 2 males slide mounted in Euparal: Finland, Taljavaaranvuoma near Kittilä, 12 July 2007. Leg. J. Salmela. Derivation of the name. The specific name is dedicated to Jukka Salmela (University of Jyväskylä, Finland), who collected the material. Diagnosis. Darkly coloured species, with wing 1.15–1.50 (1.30) mm long and AR 0.44–0.51 (0.48). Anal wing lobe strongly reduced; membrane brownish, covered with sparse macrotrichia apically. Anal point slender, with narrowed and strongly elongated tip. Superior volsella roundish, bearing two anteromedian setae. Digitus stout, with apical pear-shaped lobe and single seta at its base. Stem of median volsella strongly reduced, with group of short lamellae. Inferior volsella parallel-sided, with transversally cut apex and darkly pigmented dorsomedian ridge. Description. Adult male (measurements in Table). TABLE. Comparison of measurable characters of male Tanytarsus brundini, T. curticornis and T. salmelai sp. n. (length measurements in μm, except for wing). Character \ Species T. brundini T. curticornis T. salmelai n = 10 unless otherwise stated n = 10 n = 6 unless otherwise stated Colouration. Ground colour of thorax, scutellum, haltere, legs and abdomen olive brown; antennal pedicel, tentorium, scutal stripes, postnotum and sternum brown to fuscous or black; wing membrane brownish; C, M and radial veins distinctly darker. Head. Antenna with 13 flagellomeres; ultimate flagellomere relatively short, club-shaped. Frontal tubercles short but always present. Third palpomere longer than fourth. Wing. Membrane covered with sparse macrotrichia in distal half of cell r 4 + 5, a few macrotrichia in apical part of cell m 1 + 2 sometimes present, remaining cells bare. Veins Sc, M, RM, R 2 + 3, proximal half of R 4 + 5, M 1 + 2, Cu and false veins bare, remaining veins bearing sparse macrotrichia. R 4 + 5 ending slightly distal of M 3 + 4 and well proximal of M 1 + 2, FCu distinctly distal of RM, R 1 and Cu 1 ending about same distance along length of wing. Anal lobe of wing strongly reduced (Fig. 3). Legs. Spur of fore tibia straight, 20–25 μm long. Combs of mid and hind tibiae separated. Each comb consists of 7–9 teeth 12–15 μm long (mid tibia) and 8–10 teeth 16–20 μm long (hind tibia); each comb bears straight or slightly curved spur, 12–15 μm (mid tibia) to 28–32 μm long (hind tibia). Basitarsus of mid leg with 3 sensilla chaetica (n = 1). Hypopygium. Gonostylus straight or slightly curved and directed medially, with parallel margins tapering to widely rounded apex. Anal tergite with 2–4 median setae and small microtrichia-free area surrounding its base. Dark tergite bands of V-type, separated by slightly darker median area of anal tergite. Lateral teeth and basilateral setae absent (Fig. 4). Anal point slender, with distinctly narrowed and elongated tip, apically blunt or transversally cut, armed with 3–5 (usually 4) spinulae placed in row between crests forming a pit (Figs 15– 18); 5–8 lateral setae on each side of anal point (Fig. 4). Superior volsella roundish, slightly elongated and directed medially, with median margin transversely cut, bearing 2 strong anteromedian and 4–8 fine dorsal setae. Digitus stout, extending far beyond superior volsella, strongly bent distally, forming relatively small apical pear-shaped lobe with narrowed conical tip and single seta at its base (Fig. 21). Stem of median volsella strongly reduced, 6–8 μm long, located under superior volsella, bearing group of short lamellae; inner margin of coxite above median volsella slightly concave (Fig. 24). Inferior volsella parallel-sided, tapering to transversally cut apex, bearing darkly pigmented ridge in dorsomedian position (Fig. 27). Discussion. The presence of the pear-shaped apical lobe of the digitus and the very short median volsella makes Tanytarsus brundini and T. curticornis most similar to T. salmelai. The character best separating Tanytarsus salmelai is the narrowed and strongly elongated tip of the hypopygial anal point (Figs 15–18). The inferior volsella transversally cut apically (Figs 4, 27), the reduced anal lobe of wing, the brownish wing membrane covered with sparse macrotrichia apically (Fig. 3), the presence of frontal tubercles, the length proportions of the 3 rd and 4 th palpomere as well as the low AR and LR of all legs (Table) distinguish Tanytarsus salmelai from the two relatives compared. The enlarged apex of digitus, similar to that found in Tanytarsus salmelai, can also be observed in the Afrotropical Tanytarsus congus and T. pseudocongus. Both species fit the chinyensis group well in having the digitus-seta, and are easily separable based on highly specific hypopygial features, in particular the shape of their anal points and inferior volsellae (Ekrem 2001). Although the larval habitat of the new species is not known in any detail, it may be presumed that immatures of Tanytarsus salmelai inhabit eutrophic fens, nowadays rare in Finland. The specimens examined were sampled with a sweep net from fens surrounded by small temporary ponds (all sites) and mossy springs (Aksonjunni). Interestingly enough, no adults were collected with Malaise traps set at the same sites throughout the seasons. A correlation between flying activity of the species and its distinct wing surface reduction needs confirmation. This new species is rare. It was recorded only from three out of hundreds of sites distributed across Lapland and visited for several years.

Tanytarsus curticornis Kieffer, 1911 (Figs 2, 10���14, 20, 23, 26) Tanytarsus curticornis Kieffer, 1911: 52; Lindeberg 1963: 127; Reiss & Fittkau 1971: 100. Tanytarsus (Tanytarsus) curticornis Kieffer, 1911: Edwards 1929: 415 (partim). Material examined. FINLAND. Puruvesi, Kes��lahti, 5 August 2002, 1 male, W. Giłka. Vesij��rvi near Lahti, 11 July 2002, 1 male, W. Giłka. SWEDEN. V��sterdal��lven near S��len, 1 July 2006, river and fish-ponds, 8 males, W. Giłka. Diagnostic description. Adult male (measurements in Table). Ground colour of thorax, scutellum, haltere, legs and abdomen yellowish green; antennal pedicel, tentorium, scutal stripes, postnotum and sternum yellowish green to pale brown; wing membrane pale, with C, M and radial veins somewhat darker. Frontal tubercles usually absent. Third palpomere shorter than fourth. Wing membrane under M 3 + 4, Cu 1 and An partially free of macrotrichia; 1 / 4 proximal section of R 4 + 5, proximal half of Cu and neighbouring false veins bare (Fig. 2). Gonostylus with slight narrowing in distal part or regularly tapering to slender apex. Anal tergite with single strong basilateral seta on each side. Median setae absent. Anal point armed 4���10 (usually 7 or 8) spinulae, with blunt, widely rounded or slightly cut apex (Figs 10���14). Superior volsella with median margin transversally cut. Pear-shaped apical lobe of digitus roundish, broadly conical, stout in comparison with relatively small superior volsella (Fig. 20). Median volsella very short, inner margin of coxite above median volsella more or less straight (Fig. 23). Inferior volsella short, with broadly rounded apex (Fig. 26). Discussion. All the examined males of Tanytarsus curticornis have the lightly coloured, usually uniformly yellowish-green body, with slightly darker, pale brown tentorium, pedicel and thoracic sclerites. The colouration, however, should be treated with caution in diagnosing the species, particularly in comparison with freshly emerged specimens of Tanytarsus brundini (see diagnoses). In a number of samples taken in Lapland, we also found a few specimens which may fit Lindeberg's (1963) description of the ���Mutenianjoki population���. Our material collected from two distant sites near Tsarmi and Lemmenjoki (Inari distr.) includes pale, yellowish-green specimens with a hypopygial structure similar to that illustrated by Lindeberg (1963, fig. 6). They are undoubtedly close to Tanytarsus curticornis, but differ in having a long triangular and usually acute hypopygial anal point, bearing 4���8 spinulae placed in a row or dispersed at the base of the anal point. The specimens have a slender inferior volsella lacking an apical expansion, 2���3 median setae (which may occasionally be absent) as well as a reduced wing setation. Due to the variable nature of the diagnostic structures, an unambiguous specific diagnosis could not be formulated based on the few specimens examined. Several males were collected from a boggy area of spring brooks (helocrene) at both sites. Based on pupal descriptions (Bause 1913, Kr��ger 1945), the record of T. virens in Lapland (Thienemann 1941), and his unpublished materials, Lindeberg (l.c.) suggested a close relationship between Tanytarsus curticornis and Tanytarsus virens Kieffer, 1909. However, the systematic status of Tanytarsus virens is not certain. The species has apparently been described (merely included into a key) from adults reared by Thienemann from immatures sampled in the Heilenbecke reservoir in Westphalia (Kieffer 1909). The type series is probably lost. A single pupal exuviae of the Thienemann���s sample, which may have been used for Bause���s (1913) description, is deposited in the Zoologische Staatssammlung Muenchen. Using Langton (1991), the pupa keys out to Tanytarsus debilis (Meigen, 1830) (Spies, pers. comm.), a member of the Tanytarsus verralli species group (Reiss & Fittkau 1971)., Published as part of Gi��ka, Wojciech & Paasivirta, Lauri, 2009, Evaluation of diagnostic characters of the Tanytarsus chinyensis group (Diptera: Chironomidae), with description of a new species from Lapland, pp. 31-42 in Zootaxa 2197 on pages 38-40, DOI: 10.5281/zenodo.189527, {"references":["Lindeberg, B. (1963) Taxonomy, biology and biometry of Tanytarsus curticornis Kieff. and T. brundini n. sp. (Dipt., Chironomidae). Annales Entomologici Fennici, 29, 118 - 130.","Reiss, F. & Fittkau, E. J. (1971) Taxonomie und Okologie europaisch verbreiteter Tanytarsus - Arten (Chironomidae, Diptera). Archiv fur Hydrobiologie, Supplement 40, 75 - 200.","Edwards, F. W. (1929) British non-biting midges (Diptera, Chironomidae). Transactions of the Entomological Society of London, 77, 279 - 430.","Bause, E. (1913) Die Metamorphose der Gattung Tanytarsus und einiger verwandter Tendipedidenart. Ein Beitrag zur Systematik der Tendipediden. Archiv fur Hydrobiologie, Supplement, 2, 1 - 126.","Kruger, F. (1945) Eutanytarsariae der Gregarius - Gruppe (Dipt. Chironomidae) aus Schleswig-Holstein (Tanytarsenstudien IV). Archiv fur Hydrobiologie, 40, 1084 - 1115.","Thienemann, A. (1941) Lapplandische Chironomiden und ihre Wohngewasser. Archiv fur Hydrobiologie, Supplement 17, 1 - 253.","Kieffer, J. J. (1909) Diagnoses de noveaux Chironomides d'Allemagne. Bulletin de la Societe d'Histoire Naturelle de Metz, 26, 37 - 56.","Langton, P. H. (1991) A key to pupal exuviae of West Palaearctic Chironomidae. Privately published, Huntingdon, Cambridgeshire, 386 pp."]}

Tanytarsus brundini Lindeberg, 1963 (Figs 1, 5���9, 19, 22, 25) Tanytarsus (Tanytarsus) curticornis Kieffer, 1911: Edwards 1929: 415 (partim). Tanytarsus brundini Lindeberg, 1963: 127; Reiss & Fittkau 1971: 98. Material examined. FINLAND. Hietanen near Peranka, 2 August 2002, 6 males, W. Giłka. Inari, Vuopajanniemi, 28 July 2002, 1 male, 4 August 2003, 12 males, W. Giłka. J��nisj��rvi near N����t��m��, 26 July 2002, 1 male, W. Giłka. Korettoja on Utsjoki river, 26 July 2003, 1 male, W. Giłka. Kotka, Santalahti, 5 August 2002, 6 males, W. Giłka. Olhava near Oulu, Bothnian Gulf, 13 July 2002, 4 males, W. Giłka. P��ij��nne, 27 May 2003, 1 male, L. Paasivirta. Supru, Kuosnaj��rvi, 26 July 2002, 6 males, W. Giłka. Tervola on Kemijoki river, 13 July 2002, 1 male, 22 July 2003, 5 males, 19 July 2006, 4 males, W. Giłka. Vesij��rvi near Lahti, 11 July 2002, 1 male, W. Giłka. SWEDEN. Bure��, Skelleftebukten, Bothnian Gulf, 9 August 2003, 11 males, W. Giłka. Ljusnan river, 10 km E of Sveg, 19 July 2003, 2 males, W. Giłka. Sike��, Bothnian Gulf, 20 August 2004, 3 males, W. Giłka. Diagnostic description. Adult male (measurements in Table). Ground colour of thorax, scutellum, haltere, legs and abdomen green to brownish green; antennal pedicel, tentorium, scutal stripes, postnotum and sternum brown to dark brown or black (rarely light brown or orange in freshly emerged specimens); wing membrane pale, greenish, with C, M and radial veins somewhat darker, olive. Frontal tubercles usually absent or present as tiny swellings. Third palpomere shorter than fourth. Wing membrane below veins M and R 4 + 5, including almost entire area under M 3 + 4, Cu 1 and An covered with macrotrichia; very short proximal section of R 4 + 5 and 1 / 3 part of Cu and neighbouring false veins bare (Fig. 1). Gonostylus with slight narrowing distally. Anal tergite with pair of median setae. Basilateral setae absent. Anal point stout, armed with 4���7 (usually 4 or 5) spinulae, usually with lanceolate apical expansion (Figs 5��� 9). Superior volsella with enlarged anterolateral part and posteromedian lobe, median margin concave. Pearshaped apical lobe of digitus relatively small in comparison with stout superior volsella, bearing narrow conical tip (Fig. 19). Inner margin of coxite above median volsella distinctly concave (Fig. 22). Inferior volsella slender, apically rounded, slightly wrinkled on its dorsomedian surface (Fig. 25). Discussion. Lindeberg (1963) considered adult males of Tanytarsus brundini and T. curticornis as very similar based on their hypopygial structure. The male of Tanytarsus brundini (1) can be easily distinguished from those of T. curticornis (2) and T. salmelai (3) by the combination of characters presented below. At least one pair of median setae on the anal tergite present (1, 3) or median setae absent (2). Basilateral setae absent (1, 3) or single strong seta on each side of the anal tergite present (2). Anal point slightly lanceolate, usually with 4 or 5 spinulae (1), anal point broadly rounded or slightly cut apically, usually with 7 or 8 spinulae (2) or anal point distinctly narrowed and strongly elongated, usually with 4 spinulae (3) (Figs 5��� 9, 10 ��� 14, 15���18 respectively). Superior volsella concave (1) or transversally cut (2, 3) (Figs 19���21). Pearshaped lobe of digitus with narrow conical tip, relatively small in comparison with superior volsella (1, 3) or pear-shaped lobe of digitus roundish, relatively stout in comparison with superior volsella (2) (Figs 19���21). Inner margin of coxite above median volsella distinctly concave (1), straight (2) or slightly concave (3) (Figs 22���24). The shape of inferior volsellae of the species compared is also distinct when the structures are examined in properly mounted specimens (Figs 25���27). The wing of Tanytarsus salmelai has a distinct shape, colouration and chaetotaxy (Fig. 3), whereas the wings of T. brundini and T. curticornis are very similar (Figs 1 and 2). Slight differences can be observed in the chaetotaxy, i.e. the number of macrotrichia in cells under M 3 + 4, Cu 1, An and on veins R 4 + 5, Cu and neighbouring false veins (higher number in T. brundini). For differences in measurable characters of males Tanytarsus brundini Lindeberg, T. curticornis Kieffer and T. salmelai, see Table. In addition, Lindeberg (l.c.) based his separation of Tanytarsus brundini and T. curticornis on observations of their swarming behaviour. We confirm that swarms containing both species appear rarely. Only one sample collected at Vesij��rvi contained specimens of both species flying together in a large swarm consisting of several tanytarsine species., Published as part of Gi��ka, Wojciech & Paasivirta, Lauri, 2009, Evaluation of diagnostic characters of the Tanytarsus chinyensis group (Diptera: Chironomidae), with description of a new species from Lapland, pp. 31-42 in Zootaxa 2197 on pages 35-38, DOI: 10.5281/zenodo.189527, {"references":["Lindeberg, B. (1963) Taxonomy, biology and biometry of Tanytarsus curticornis Kieff. and T. brundini n. sp. (Dipt., Chironomidae). Annales Entomologici Fennici, 29, 118 - 130.","Edwards, F. W. (1929) British non-biting midges (Diptera, Chironomidae). Transactions of the Entomological Society of London, 77, 279 - 430.","Reiss, F. & Fittkau, E. J. (1971) Taxonomie und Okologie europaisch verbreiteter Tanytarsus - Arten (Chironomidae, Diptera). Archiv fur Hydrobiologie, Supplement 40, 75 - 200."]}

Tanytarsus salmelai sp. n. (Figs 3, 4, 15���18, 21, 24, 27) Type material. Holotype male, slide mounted in Canada balsam: Finland, Arcto-Alpine ecoregion, Aksonjunni, 36 km south of Nuorgam, Utsjoki, 2 July 2007. Paratypes. 1 male: same data as holotype; 2 males: Finland, Northern boreal ecoregion, Vasanvuoma near Kittil��, 26 June 2007; 2 males slide mounted in Euparal: Finland, Taljavaaranvuoma near Kittil��, 12 July 2007. Leg. J. Salmela. Derivation of the name. The specific name is dedicated to Jukka Salmela (University of Jyv��skyl��, Finland), who collected the material. Diagnosis. Darkly coloured species, with wing 1.15���1.50 (1.30) mm long and AR 0.44���0.51 (0.48). Anal wing lobe strongly reduced; membrane brownish, covered with sparse macrotrichia apically. Anal point slender, with narrowed and strongly elongated tip. Superior volsella roundish, bearing two anteromedian setae. Digitus stout, with apical pear-shaped lobe and single seta at its base. Stem of median volsella strongly reduced, with group of short lamellae. Inferior volsella parallel-sided, with transversally cut apex and darkly pigmented dorsomedian ridge. Description. Adult male (measurements in Table). TABLE. Comparison of measurable characters of male Tanytarsus brundini, T. curticornis and T. salmelai sp. n. (length measurements in ��m, except for wing). Character \ Species T. brundini T. curticornis T. salmelai n = 10 unless otherwise stated n = 10 n = 6 unless otherwise stated Colouration. Ground colour of thorax, scutellum, haltere, legs and abdomen olive brown; antennal pedicel, tentorium, scutal stripes, postnotum and sternum brown to fuscous or black; wing membrane brownish; C, M and radial veins distinctly darker. Head. Antenna with 13 flagellomeres; ultimate flagellomere relatively short, club-shaped. Frontal tubercles short but always present. Third palpomere longer than fourth. Wing. Membrane covered with sparse macrotrichia in distal half of cell r 4 + 5, a few macrotrichia in apical part of cell m 1 + 2 sometimes present, remaining cells bare. Veins Sc, M, RM, R 2 + 3, proximal half of R 4 + 5, M 1 + 2, Cu and false veins bare, remaining veins bearing sparse macrotrichia. R 4 + 5 ending slightly distal of M 3 + 4 and well proximal of M 1 + 2, FCu distinctly distal of RM, R 1 and Cu 1 ending about same distance along length of wing. Anal lobe of wing strongly reduced (Fig. 3). Legs. Spur of fore tibia straight, 20���25 ��m long. Combs of mid and hind tibiae separated. Each comb consists of 7���9 teeth 12���15 ��m long (mid tibia) and 8���10 teeth 16���20 ��m long (hind tibia); each comb bears straight or slightly curved spur, 12���15 ��m (mid tibia) to 28���32 ��m long (hind tibia). Basitarsus of mid leg with 3 sensilla chaetica (n = 1). Hypopygium. Gonostylus straight or slightly curved and directed medially, with parallel margins tapering to widely rounded apex. Anal tergite with 2���4 median setae and small microtrichia-free area surrounding its base. Dark tergite bands of V-type, separated by slightly darker median area of anal tergite. Lateral teeth and basilateral setae absent (Fig. 4). Anal point slender, with distinctly narrowed and elongated tip, apically blunt or transversally cut, armed with 3���5 (usually 4) spinulae placed in row between crests forming a pit (Figs 15��� 18); 5���8 lateral setae on each side of anal point (Fig. 4). Superior volsella roundish, slightly elongated and directed medially, with median margin transversely cut, bearing 2 strong anteromedian and 4���8 fine dorsal setae. Digitus stout, extending far beyond superior volsella, strongly bent distally, forming relatively small apical pear-shaped lobe with narrowed conical tip and single seta at its base (Fig. 21). Stem of median volsella strongly reduced, 6���8 ��m long, located under superior volsella, bearing group of short lamellae; inner margin of coxite above median volsella slightly concave (Fig. 24). Inferior volsella parallel-sided, tapering to transversally cut apex, bearing darkly pigmented ridge in dorsomedian position (Fig. 27). Discussion. The presence of the pear-shaped apical lobe of the digitus and the very short median volsella makes Tanytarsus brundini and T. curticornis most similar to T. salmelai. The character best separating Tanytarsus salmelai is the narrowed and strongly elongated tip of the hypopygial anal point (Figs 15���18). The inferior volsella transversally cut apically (Figs 4, 27), the reduced anal lobe of wing, the brownish wing membrane covered with sparse macrotrichia apically (Fig. 3), the presence of frontal tubercles, the length proportions of the 3 rd and 4 th palpomere as well as the low AR and LR of all legs (Table) distinguish Tanytarsus salmelai from the two relatives compared. The enlarged apex of digitus, similar to that found in Tanytarsus salmelai, can also be observed in the Afrotropical Tanytarsus congus and T. pseudocongus. Both species fit the chinyensis group well in having the digitus-seta, and are easily separable based on highly specific hypopygial features, in particular the shape of their anal points and inferior volsellae (Ekrem 2001). Although the larval habitat of the new species is not known in any detail, it may be presumed that immatures of Tanytarsus salmelai inhabit eutrophic fens, nowadays rare in Finland. The specimens examined were sampled with a sweep net from fens surrounded by small temporary ponds (all sites) and mossy springs (Aksonjunni). Interestingly enough, no adults were collected with Malaise traps set at the same sites throughout the seasons. A correlation between flying activity of the species and its distinct wing surface reduction needs confirmation. This new species is rare. It was recorded only from three out of hundreds of sites distributed across Lapland and visited for several years., Published as part of Gi��ka, Wojciech & Paasivirta, Lauri, 2009, Evaluation of diagnostic characters of the Tanytarsus chinyensis group (Diptera: Chironomidae), with description of a new species from Lapland, pp. 31-42 in Zootaxa 2197 on pages 32-35, DOI: 10.5281/zenodo.189527, {"references":["Ekrem, T. (2001) A review of Afrotropical Tanytarsus (Diptera: Chironomidae). Tijdschrift voor Entomologie, 144, 5 - 40."]}