Stenus (Nestus) rigidus Casey, 1884

Ryvkin, Alexandr B., 2014, Stenus (Nestus) Pluvius Sp. N., With Notes On Some Related Species (Coleoptera: Staphylinidae: Steninae), Acta Biologica Universitatis Daugavpiliensis 14 (2), pp. 187-205 : 191-195

Stenus (Nestus) rigidus Casey, 1884 sp. propria rigidus Casey, 1884: 119 rigidus ; Casey, 1892: 711

ageus Casey, 1884: 116

ageus ; Herman, 2001: 2047

ageus ; Smetana, 2004: 553

ageus ; Shavrin & Puthz, 2007: 109

ageus ; Puthz, 2012: 292, 296

ageus ; Puthz, 2013a: 862

dissociatus Eppelsheim, 1893: 54

parvulus L. Benick, 1914: 150

gerhardti L. Benick, 1915a: 233

New material examined. USA: 1 female ( OSU): Camden, N.J. 23.II.; H.W.Wenzel Collector; H.W.Wenzel Collection.— 1 female ( OSU): Huachu. Mts, Ariz. VII.26.; Miller Can. HA.Wenzel [leg.]; H.W.Wenzel Collection.— 1 female ( AR): Alaska 76–76, Cirkl Hot Springs. 24.08.1976. E.Matis leg.— 5 males, 1 female ( UAM): ALASKA: Sheenjek River, wet meadow. 1– 30.06.2000. A.Johnson leg.— 1 male, 1 female ( UAM): ALASKA: Sheenjek River, open spruce. 1– 30.06.2000. A.Johnson leg.— 2 females ( UAM): ALASKA: [Arctic Nat. Wild. Ref. ( ANWR)] Sheenjek R, wet meadow. Trans 5, trap 5. 18.06.2000. A.Johnson leg.— RUSSIA: SVERDLOVSK AREA: 1 female ( ZIN): Perm Government, near Ekaterinburg, Uktus. 09.06.1910. G.G.Jakobson leg.[ ‘ argus Gr. L.Benick det.’]— YAMALO-NENETS AUTONOMOUS REGION: 1 male ( AR): South of the Yamal Peninsula, Priuralskiy District, Tarcheda-Yakha River near mouth. 23.07.1980. E.M.Veselova leg.— 1 female ( AR): South of the Yamal Peninsula, Priuralskiy District, near Shchuchye trading station. He4a: Calamagrostis lapponica . 29.07.1980. E.M.Veselova leg.— 1 male ( AR): South of the Yamal Peninsula, Priuralskiy District, near Shchuchye trading station. 11.08.1980. E.M.Veselova leg.— KHANTY-MANSI AUTONOMOUS REGION: 1 male, 1 female ( AR): near Shapsha, 61.085°N 69.458°E, 42 m a.s.l. 01– 04.08.2010. K. Tomkovich leg.— 1 male ( AR): Surgutskiy District, Surgutskiy Nature Refuge, Ob’ River basin, right side of Materikovyi Pasl Channel, lake shore: Carex spp. , Comarum palustre, Lamiaceaegen. sp., Climacium sp. , Plagiomnium sp. etc. 10.08.2000. A.B.Ryvkin leg.— 1 male ( AR): Khanty-Mansi Autonomous Region, Surgutskiy District, Yuganskiy Nature Reserve, Vuya-Yany River near Ay-Vuya-Yany River mouth, clay river banks near mouth of small left confluent (500 m below field research station): Carex spp. , Poaceae , Mentha sp. ,? Trollius sp. etc. 25.08.2000. A.B.Ryvkin leg.— TYUMEN AREA: 1 male ( AR): Uvatskiy District, 11 km S of Gornoslinkino, clayish right side of Irtysh River (narrow fold at rill mouth) up-stream of Tobolsk Field Research Station of Severtsov Institute, leaf litter under Salix sp. with small true mosses, Marchantia sp. , Equisetum sp. , Carex sp. , Calamagrostis sp. etc. 04.06.2004. A.B.Ryvkin leg.— 1 male ( AR): same locality and collector, plant debris and leaf litter at margin of inundated flood-plain of Varpak River: Carex sp. , Poaceae , Lythrum sp. , Salix sp. on gentle slope, aspen trees on steep slope, depression in the ground with aspen leaf drift. 07.06.2004.— TAYMYR AUTONOMOUS REGION: 4 males, 2 females ( AR): Putorana Highland, nr. Ayan Lake, Kapchug River, riverside tundroid, bog with mosses and Eriophorum sp. 11.06.1983. K.Yu.Eskov leg.— 1 male ( AR): Putorana Highland, Ayan Lake near Ayan River source, mossy coastal osier-bed. 07.07.1983. K.Yu. Eskov leg.— 2 males ( AR): Putorana Highland, Ayan Lake near Ayan River source, lakeside tundroid, under willow & alder bushes. 31.07.1983. K.Yu.Eskov leg— 1 male ( AR): Putorana Highland, Ayan Lake near source of Ayan River, larch forest with Equisetum sp. at debris cone. 21.08.1983. K.Yu.Eskov leg.— KRASNOYARSK TERRITORY: 1 female ( AR): ‘Stolby’ Nature Reserve, near Kandalak cordon, Mana River bank, sweeping on grass near water. 24.08.1994. I.A.Ushakov leg.— 2 females ( AR): Turukhanskiy District, Yeloguy River 7–10 km below Tyna River mouth, 70 m a.s.l., Carex spp. , Poaceae gen. spp., Comarum palustre , etc. on lakeside (tussocks). 22.07.1989. A.B.Ryvkin leg.— 1 male, 1 female ( AR): Turukhanskiy District, Yeloguy Refuge, Yeloguy River 6 km below Tyna River mouth, in litter on swamped shore of forest lake with Filipendula ulmaria , Ribes nigrum , Alnus sp. , Betula sp. 27.07.1992. V.B.Semenov leg.— 1 female ( AR): Turukhanskiy District, Yeloguy Refuge, Tyna River 12 km up-stream of river mouth, under mosses on stony bank of river. 12.08.1992. V.B.Semenov leg.— 2 males ( AR): 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 between those at open river bank. 06.08.1992. A.B.Ryvkin leg.— 1 male, 1 female ( AR): Turukhanskiy District, Bakhta River basin: near Keteollo Lake, 325 m a.s.l., among Carex spp. , Poaceae gen. spp. etc. on swampy SW lakeside near old hut. 21.08.1992. A.B.Ryvkin leg.— EVENKIA: 1 male, 2 females ( AR): same locality and collector, under Salix sp. 19.07.1982.— 1 male ( AR): near Tura, Kochechum River bank, alder bushes. 29.08.1982. K.Yu.Eskov leg.— 1 female ( AR): Baykitskiy District, Bakhta River head, 1, 5 km up-stream of Gutkengne River mouth, 470 m a,s.l., swampy bank of old channel with tussocks: in mosses and litter among Carex spp. , Poaceae gen. sp., Filipendula ulmaria , Geranium sp. , Trollius etc. 14.08.1991. A.B.Ryvkin leg.— 1 female ( AR): Baykitskiy District, Central Siberian Biosphere Reserve, Stolbovaya River basin: Birapchana River, 3–5 km below confluence of the Levaya Birapchana and Pravaya Birapchana Rivers, 460–480 m a.s.l., swamps at rill mouth: Carex sp. with Trollius asiaticus , Geranium sp. , Filipendula palmata , etc. on tussocks. 03.07.1988. A.B.Ryvkin leg.— 2 males, 4 females ( AR): same locality and collector, 480 m a.s.l., small eutrophic swamp at river bank ( Carex spp. , mosses etc.). 05.07.1988.— 1 male ( AR): Baykitskiy District, Central Siberian Biosphere Reserve, Stolbovaya River basin: Dulkuma River (I), 12–15 km up-stream of Topkaya River mouth, 210 m a.s.l., litter, drift and mosses under Alnus , Salix , Betula at river bank. 27.06.1990. A.B.Ryvkin leg.— 1 male, 1 female ( AR): Baykitskiy District, Central Siberian Biosphere Reserve, Stolbovaya River basin, Dulkuma River 4–5 km up-stream of river mouth, 105 m a.s.l., river bank: shingles, stones, Carex spp. , Poaceae , mosses. 06.07.1990. A.B.Ryvkin leg.— TUVA: 4 females ( AR): Todja District, Todja Basin, Malyi Azas Lake, near Toora-Khem River source, 940 m a.s.l., swamp with tussocks at lake shore: Carex spp. , Poaceae , Trollius asiaticus , Plagiomnium sp. etc. 16.06.1991. A.B.Ryvkin leg.— 3 males, 5 females ( AR): Todjenskiy District, Bol’shoy Yenisey (Biy-Khem) River basin, 2 km S of the Great Waterfall, lake on left confluent of Biy-Khem River, 1070 m a.s.l, mosses and litter on swamp and in lakeside swamped sparse forest (from water to foot of slope): Larix sibirica , Picea obovata , Betula spp. , Vaccinium uliginosum , V. vitis-idaea , Oxycoccus sp. , Ledum palustre , Carex spp. , Salix sp. , Linnaea borealis , Sphagnum spp. , Pleurozium schreberi , Hylocomium splendens , etc. 15.06.1992. A.B.Ryvkin leg.— IRKUTSK AREA: 1 male, 1 female ( ZIN): Irkutsk. V.Ye.Yakovlev leg.; 115. [ ‘ argus Gr. L.Benick det.’].— 1 male ( ZIN): same locality and collector; 238.[ ‘ argus Gr. L.Benick det.’; ‘52’].— 1 female ( ZIN): same locality and collector; 273.[ ‘ argus Gr. L.Benick det.’]— 1 male ( ZIN): same locality and collector; 276.[ ‘ argus Gr. L.Benick det.’]— 1 female ( AR): Kazachinsko-Lenskiy District, 9 km SO Magistralnyi, Kirenga River, river bank: Carex sp. , Filipendula ulmaria (He) . 16.07.1984. A.B.Ryvkin leg.— BURYATIA: 2 males ( DUBC): E Siberia, Bauntovskiy district, left side of Talaya river, N54°50’826” E113°32’731”. 23.08.2010. I.V.Enushchenko leg.— TCHITA AREA: 1 male ( AR): Uletovskiy District, Sokhondinskiy Nature Reserve, valley of stream without name (right confluent of Ingoda River), 2 km NE of Ashagley winter hut. N 54°36.7`E 111°07.952`, h= 1350 m a.s.l. 20.07.2009. A.V.Shavrin, I.V.Enushchenko leg.— YAKUTIA: 1 female ( ZIN): 5 verst off Yakutsk, suburban settlement. 18.06.1925. Bianki leg. [;] Yakutian research expedition of Acad. of Sci.[ ‘ argus Gr. L.Benick det.’; ‘46’]— 1 male ( ZIN): Ytykkhaya 40 verst off Yakutsk. 26.06.1901. Herz leg.[ ‘ argus Gr. L.Benick det.’].— 1 female ( ZIN): Amginskaya Sloboda, Yakutsk Region. 09.08.1925. Bianki leg. [;] Yakutian research expedition of Acad. of Sci.[;] Grass swamp[;] Lakeside.[ ‘ morio Gr. L.Benick det.’]— 1 female ( ZIN): Amginskaya Sloboda. 12.08.1925. Bianki leg. [;] Yakutian research expedition of Acad. of Sci.[;] Grass swamp[;] Lakeside. [ ‘ argus Gr. L.Benick det.’]— 1 female ( ZIN): 17 verst off III camp, Amginsk–Yakutsk road. 15.08.1925. Bianki leg. [;] Yakutian research expedition of Acad. of Sci.[ ‘ argus Gr. L.Benick det.’; ‘19’]— 1 female ( ZIN): same locality and collector, XIV-1 dry meadow of S slope. 01.08.1958.— 4 females ( AR): Ordjonikidzevskiy District, Lyutenge River basin, near Noochuga, leaf litter on small swamp with Larix gmelinii , Salix sp. , Ledum palustre , Carex spp. , Iris sp , Poaceae etc. 28.07.1984. A.B.Ryvkin leg.— 1 male ( AR): Tomponskiy District, Aldan River basin, 3 km NE of Khandyga, swamp with Carex spp. , Iris sp. , Betula sp. , Larix gmelinii . 31.07.1984. A.B.Ryvkin leg.— 1 male ( AR): 25 km S of Yakutsk, left side of Lena River. 11.07.2001. S.A.Kurbatov leg.— AMUR AREA: 1 female ( AR): upper reaches of Bolshoy Ol’doy River. 24.09.1958. O.N.Kabakov leg.— 1 female ( ZIN): Klimoutsy, 40 km W of Svobodnyi, Iris - Carex meadow, XIg–1. 14.06.1958. Zinovyev leg.— 1 female ( ZIN): same locality and collector, XIV-1 dry meadow of S slope. 01.08.1958.— 1 male, 1 female ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Nora River basin near Maltsevskiy cordon, mosses and plant debris on swampy flood-plain lakeside: Carex spp. , Calamagrostis sp. , Filipendula palmata , Geranium sp. , Comarum palustre , Spiraea sp. , Salix sp. , Sphagnum? girgensohnii , Sph. squarrosum , Polytrichum commune , P. sp., Climacium sp. , Iris sp. , etc. 28.08.2004. A.B.Ryvkin leg.— 1 male, 2 females ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Selemdzha River basin near Burundushka River mouth, clayish and sandy-clayish river banks with Carex spp. , Poaceae , Salix spp. , Equisetum spp. , etc. 03.08.2004. A.B.Ryvkin leg.— 2 males, 3 females ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Selemdzha River basin near Dvadtsatikha cordon, open swamp: Carex sp. , Spiraea spp. , Geranium sp. , Vicia sp. , Poaceae , Salix spp. , Filipendula palmata , sparse Plagiomnium sp. , Sphagnum sp. , Polytrichum sp. , etc. 04.08.2004. A.B.Ryvkin leg.— 1 male ( AR): same locality and collector, plant debris and sweeping on open swamp: Carex sp. , Spiraea spp. , Geranium sp. , Vicia sp. , Poaceae , Salix spp. , Filipendula palmata , sparse Plagiomnium sp. , Sphagnum sp. , Polytrichum sp. , etc. 08.08.2004.— 2 males ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, rill (left confluent of Nora River) up-stream of Gryashchinskaya Mt., true mosses and plant debris among Carex spp. , Poaceae , Alnus sp. , Padus asiatica , Salix sp. , etc. 26.08.2004. A.B.Ryvkin leg.— 1 male, 7 females ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Nora River basin near Meun River mouth, small swamp with Carex spp. , Poaceae & Sphagnum squarrosum . 19.08.2004. A.B.Ryvkin leg.— 2 males, 9 females ( AR): same locality, biotope & collector. 20.08.2004.— 10 males, 9 females ( AR): Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin near Burunda cordon, plant debris and mosses (+sweeping) on swampy sides of flood-plain lake: Carex spp. , Poaceae , Spiraea sp. , sparse Climacium sp. , Hypnum sp. , Sphagnum sp. , Polytrichum sp. , etc. 09.09.2004. A.B.Ryvkin leg.— 1 male ( AR): Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin, 0.5 km NW of Burunda cordon, moss and plant debris at edge of swamp: tussocks of Poaceae with Carex sp. , young growth of Betula sp. , Salix sp. , Spiraea sp. , and small true mosses. 07.10.2004. A.B.Ryvkin leg.— 1 female ( AR): Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin, 1 km SE of Burunda cordon, mosses and plant debris among sedge tussocks on wide Carex - Eriophorum -gramineous swamp with small true mosses, Sphagnum squarrosum, Sph. sp., Ledum palustre , Vaccinium uliginosum , sparse Salix sp. , young growth of Betula sp. , etc. 21.09.2004. A.B.Ryvkin leg.— 2 males, 1 female ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Burunda River near Ozyornyi Rill mouth, mosses and plant debris among sedge-gramineous tussocks on very gentle slope near intermittent channel: Carex spp. , Calamagrostis sp. , Polytrichum sp. and other true mosses, Spiraea sp. , etc. 27.09.2004. A.B.Ryvkin leg.— 11 males, 11 females ( AR): same locality, biotope & collector. 28.09.2004.— 1 female ( AR): same locality and collector, mosses and leaf litter under Salix sp. and Alnus sp. with separate tussocks of Carex sp. , Plagiomnium sp. , etc. on flood-plain (near old channel). 30.09.2004.— 1 female ( AR): same locality and collector, Plant debris and mosses among tussocks of Carex spp. and Poaceae with Spiraea sp. , Vicia sp. , Plagiomnium sp. , etc. on open flood-plain depression with tracks of Capreolus capreolus . 01.10.2004.— 1 male ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, lower reaches of Chervinka River, mosses, ferns, leaf litter, plant debris on banks of river and intermittent rill with tussocks of Carex spp. , Poaceae , Spiraea spp. , Salix spp. , Betula? divaricata , undergrowth of Betula platyphylla , etc. 30.06.2005. E.M.Veselova & A.B.Ryvkin leg.— 1 female ( AR): Selemdzhinskiy District, Selemdzha River basin, flood-plain of Aldikon River near Norsk, mosses and leaf litter under Salix sp. and along the edge of open sedge-gramineous tussock swamp. 05.09.2004. A.B.Ryvkin leg.— 1 male ( AR): Selemdzhinskiy District, Selemdzha River basin, 2 km up-stream of Norsk, mosses and plant debris among Carex spp. , Poaceae , Filipendula palmata , Spiraea sp. , Salix sp. , Padus sp. , etc. on swampy side of small drainage lake (dammed rill). 06.09.2004. A.B.Ryvkin leg.— 3 males, 4 females ( AR): Selemdzhinskiy District, 3 km SW of Norsk, Aldikon River near mouth, 200 m a.s.l., plant debris and sparse mosses among sedges and Poaceae gen. spp. on gentle bank of river. 21.08.2006. A.B.Ryvkin leg.— 2 males, 1 female ( AR): Selemdzhinskiy District, near Fevral’sk, 268th km of Belogorsk– Fevral’sk road, Tikhiy rill, 275 m a.s.l., mosses and plant debris between sedge & gramineous tussocks among Alnus sp. , Salix sp. , Spiraea sp. with Sphagnum squarrosum, Sph. spp., etc. 08.10.2008. A.B.Ryvkin leg.— 1 male ( AR): same locality, collector & biotope. 14.10.2008.— 1 female ( AR): Selemdzhinskiy District, Selemdzha River basin, 5 km up-stream of Ekimchan, up-stream of Unerikan River mouth, 500 m, mosses and litter on spacious swamp near lakeside: Vaccinium uliginosum , Ledum palustre , Chamaedaphne calyculata , Betula divaricata , undergrowth of Betula sp. and Larix gmelinii , Carex spp. , Poaceae gen. spp., Comarum palustre , Salix spp. , Sphagnum spp. , Polytrichum spp. , etc. 31.08.2005. A.B.Ryvkin leg.— 2 males, 3 females ( AR): Selemdzhinskiy District, Norskiy Nature Reserve, Burunda River bank 3 km up-stream of mouth, 215 m a.s.l., mosses and plant debris among sedges etc. and on shingle bed. 03.08.2006. E.M.Veselova &A.B.Ryvkin leg.— KHABAROVSK TERRITORY: 1 female ( AR): Okhotskiy District, Khetana River (confluent of Amka River, Ulya River basin), 7 km up-stream of river mouth. 12.07.1985. V.Zherikhin, A.Rasnitsyn, D. Shcherbakov leg.— 3 males, 2 females ( AR): Verkhnebureinskiy District, 4th km of Chegdomyn–Urgal road, mosses and plant debris on swampy sides of wayside lake with tussocks of Carex spp. and Poaceae gen. sp., Scirpus sp., Comarum palustre , Ledum palustre , Chamaedaphne calyculata , Vaccinium uliginosum , V. vitis-idaea , Betula divaricata , Larix gmelinii , Sphagnum spp. , Aulacomnium sp. , Polytrichum sp. 05.10.2006. A.B.Ryvkin leg.— 1 male ( OB): Verkhnebureinskiy District, Bureinskiy Nature Reserve, right side of Levaya Bureya River up-stream of Malyi Sigda-Makit River mouth, 640 m a.s.l., plant debris among Carex spp. with Poaceae gen. spp. and Alnus sp. on swampy bank of old channel. 07.07.2011. A.B.Ryvkin leg.— 2 females ( AR): Verkhnebureinskiy District, Dublikanskiy Nature Refuge, right side of Dublikan River valley, 1 km N of cordon, leaf litter and plant debris on small open dried flood-plain swamp with tussocks of Carex spp. , Filipendula palmata , Spiraea spp. , Sorbaria sorbifolia , Matteuccia struthiopteris , etc. 31.08.2008. A.B.Ryvkin leg.— MAGADAN AREA: 1 female ( AR): Upper reaches of Kolyma River, 78-11, 3 km W of Sibit-Tyhellakh. 23.06.1978. E.G.Matis leg.— 1 male ( AR): Atargan, 10 km E of Ola. 13.06.1979. E.G.Matis leg.— 1 female ( AR): Ten’kinskiy District, near Sibit-Tyhellakh, pitfall trap. 04– 14.06.1983. D.I.Berman leg.— KAMCHATKA TERRITORY: 1 female ( ZIN): Ust’- Kamchatskaya Koshka. 07.04.1908. A. Derzhavin leg. [ ‘ argus Gr. L.Benick det.’]— 1 female ( ZIN): same locality and collector. 11.06.1909. [ ‘ argus Gr. L.Benick det.’; ‘154’]— 1 female ( AR): Kozyrevsk. 22.06.1975. B.A.Korotyayev leg.

Remarks. Both S. rigidus and S. ageus were described in Casey’s Revision (1884) from the USA (Cambridge, Massachusetts). In the Coleopterological notices IV (1892), acting as First Reviser, Casey himself put S. ageus in the synonymy of S. rigidus . But after Bernhauer & Schubert (1911), based on erroneous earlier concept ( Hamilton 1889 etc), had mistakenly synonymized both names with S. argus Gravenhorst, 1806 , the confusion was fixed in the taxonomy of the species. And even when L. Benick (1925), and then Puthz (1971a, 1973), restored the species, these authors regarded S. ageus as a valid name. Though the senior synonym has not been used as a valid name after 1899 (Article 23.9.1 of ICZN), I can not find ‘at least 25 works, published by at least 10 authors in the immediately preceding 50 years’ where ‘the junior synonym or homonym has been used for a particular taxon, as its presumed valid name’ (Article 23.9.2 of ICZN); I have found only five such references after 2000, that, with thirteen references listed by Herman (2001), amounts only eighteen works. Therefore, under Articles 24.2.1 and 24.2.2 of ICZN, the valid name for the species is Stenus rigidus Casey, 1884 .

Stenus rigidus is extremely variable species in both external characters and the shape of the aedeagus, but it seems impossible at present time to divide it into separate taxa. It is widely distributed in North America and Northern Asia (see the New material section above); its distribution in Northern and Central Europe requires a further careful study.

195