Stenus (Nestus) nitens Stephens 1833

Stenus (Nestus) nitens Stephens, 1833

(Fig. 1 A–D)

Stenus nitens Stephens, 1833: 300.

Stenus nitens – Waterhouse 1858: 28. — J. Sahlberg 1876: 58. — Poppius 1899: 39. — J. Sahlberg 1899: 340. — J. Sahlberg 1900: 29. — Szujecki 1960: 297. — Puthz 1971b: 34. — Tichomirova 1982: 213. — Pisanenko & Puthz 1991: 170. — Puthz & Zanetti 1995: 18. — Shavrin & Puthz 2007: 125.

Stenus (Nestus) nitens – Jakobson 1909: 481. — Reitter 1909: 158. — Renkonen 1935: 29. — Szujecki 1961: 34. — Palm 1961: 90. — Puthz 1967d: 293. — Puthz 1971a: 82. — Tichomirova 1973: 173. — Shilov 1975: 58. — Ryvkin 1987: 159. — Dauphin 1993: 188. — Semenov 2004: 12.

Stenus (Nestus) nitens <?!> – Poppius 1909a: 16. — Bordoni 2004: 120.

Stenus aemulus Erichson, 1839: 541.

Stenus aemulus – Hochhuth 1872: 154 (as S. aemulus Gyllenhal).

FINLAND: 1 ♂, ‘Fennia. Reitter’, ‘ Stenus nitens Steph. ’, ‘c.[ollection] of A. Jakovlev’ <printed label in Russian> (ZIN); 1 ♂, 1 ♀, ‘Fennia’<printed label on red paper>, ‘ J. Sahlb.[erg]’ <printed on yellowed white rectangle>, ‘ Stenus nitens Stph. ’ <black Indian ink> (ZIN: ex coll. Semenov-Tian-Shanskiy); 1 ♂, ‘Helsingfors. 4126[= Stenus nitens Steph.] – 3’ (ZIN).

RUSSIA: 1 ♀, ‘ Petropolis. 4126[= Stenus nitens Steph.] – 5’, ‘ nitens Steph. ’ (ZIN); 1 ♀, Tyumen Area, Nefteyuganskiy District, 90 km S of Nefteyugansk, near Bolshoye Kayukovo Lake, geobotanical field research station of Moscow University, floating island on sedge eutrophic swamp: in hummock base, 20 Aug. 1985, R.A. Rakitov leg. (AR); 1 ♂, 2 ♀♀, Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Nyogus’yakh River, Bisarkina cordon, moss and litter on swamp amid flood plain forest near foot of slope: Menyanthes trifoliata, Equisetum spp., Sphagnum squarrosum (sparse), Sph. ? centrale, Sph. spp., Nardosmia frigida, Carex spp., Poaceae gen. sp., Salix sp., Comarum palustre, Filipendula ulmaria,? Tomenthypnum sp., Plagiomnium sp., etc., 27 Jul. 1998, A.B. Ryvkin leg. (AR); 1 ♂, Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Nyogus’yakh River basin near Pechpan’yakh River mouth, mosses and litter on large swamp: Carex spp., Comarum palustre, Equisetum sp., Nardosmia frigida, Eriophorum sp., Poaceae gen. spp., Rumex sp., Chamaenerion angustifolium, Salix sp.,? Aulacomnium sp., Plagiomnium sp., Ptilium cristacastrensis, Sphagnum ? russovii, Sph. sp. etc., 15 Sep. 2000, A.B. Ryvkin leg. (AR); 1 ♂, 1 ♀, Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Ay-Magromsy River basin, Medvezhyi Ugol cordon, mosses and litter at southern border of sedge-mossy swamp: Carex rostrata, C. spp., Comarum palustre, Equisetum spp., Sphagnum girgensohnii, Sph. spp., Plagiomnium sp., Aulacomnium sp., Calamagrostis sp., Menyanthes trifoliata, etc. among sparse young birches (t=+10°– +5° C), 4 Oct. 2002, A.B. Ryvkin leg. (AR); 1 ♂, Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Malyi Yugan River basin, 3–5 km SW of cordon at Kol-Kochen-Yagun River, mosses and litter by swampy margin at N side of lake: Carex spp., Sphagnum spp., Poaceae gen. spp., 26 Sep. 1999, A.B. Ryvkin leg. (AR); 1 ♀, Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Malyi Yugan River, cordon below Lyarykni River mouth, open swamp with tussocks of Carex spp. and Calamagrostis sp. with Comarum palustre, Salix sp., Sphagnum squarrosum, Sph. spp.,? Aulacomnium sp. etc. among sparse young Betula sp., 17 Aug. 2003, A.B. Ryvkin leg. (AR); 1 ♂, Krasnoyarsk Territory, Turukhanskiy District, Bakhta River basin, near Keteollo Lake, Noya River source, 323 m a.s.l., mosses and litter among Carex spp., Filipendula ulmaria, Poaceae on tussocks and among those at open river bank, 6 Aug. 1992, A.B. Ryvkin leg. (AR); 1 ♂, Evenkia, Baykitskiy District, Central Siberian Biosphere Reserve, Stolbovaya River 8 km up-stream of river mouth, 60 m a.s.l., mosses and litter on open swamp with Carex spp., Comarum palustre, sparse Menyanthes trifoliata, true mosses, Sphagnum spp. etc., 20 Sep. 1991, A.B. Ryvkin leg. (AR); 1 ♂, Evenkia, Baykitskiy District, Podkamennaya Tunguska River, 175 km up-stream of river mouth, near Belaya Kosa Island, 55 m a.s.l., swamp with Comarum palustre, Sphagnum spp., Equisetum sp., Plagiomnium sp., Carex spp., etc., 23 Aug. 1990, A.B. Ryvkin leg. (AR).

Terra typica: ‘London; Suffolk’; for aemulus: ‘Brandenburg’. The species is known from C & N Europe and W Siberia (Tichomirova 1973). Hochhuth (1872) reported it (as aemulus Gyllh. <sic!>) for the Kiev Government (‘Ziemlich selten’); J. Sahlberg cited it for N Karelia (1876: ‘Nordligast har jag funnit den vid Soukelo i Ryska Lappmarken (66°40’)’), ‘Peninsula Kola, Petschora’ (1899); Jakobson (1909) summarized records for ‘Arkhangelsk Government (Lapponia, Pechora), <…> Olonets Government, St.-Petersburg Government, Kiev Government’. Puthz (Pisanenko & Puthz 1991) mentioned that ‘Aus der europäischen Sowjetunion war diese Art Horion 1963 unbekannt’, but, besides the records named above, Puthz (1971a) himself cited an additional find for the Leningrad Area (‘Viipuri’=Vyborg); Tichomirova (1982) recorded the species for the Moscow Area. The sketchy figure of an aedeagus provided by Bordoni (2004) for S. nitens from Italy (‘Veneto: Verona’) seems to belong to a specimen of another species. Unfortunately the specimen which has been figured by Bordoni is not found in Museo Civico di Storia Naturale, Verona (A. Zanetti pers. comm.); thus, the Italian records of the species require a confirmation. The new material proves that the species is widely distributed in W & C Siberia. The E Siberian records by Poppius (1909a: ‘An der mittleren Lena weit verbreitet, aber einzeln. <...> Olekminsk, Ytyk-haja, Önkyr-yrjä, Ust-Aldan, zwischen Ust-Aldan und Batylym, Shigansk’) have been confirmed by neither subsequent writers nor the new material. The aforecited material from W Evenkia seems to provide the easternmost verified records of the species until now. The shape of the aedeagus of the male from Evenkia corresponds well to that of the specimen from European Russia (see Fig. 1 A–D).