Stenus (Nestus) illotulus Puthz, 1972

Ryvkin, Alexandr B., 2012, New species and records of Stenus (Nestus) of the canaliculatus group, with the erection of a new species group (Insecta: Coleoptera: Staphylinidae: Steninae), European Journal of Taxonomy 13, pp. 1-62 : 16-18

Stenus (Nestus) illotulus Puthz, 1972

( Fig. 2C, D )

Stenus (Nestus) illotulus Puthz, 1972b: 169 .

Stenus illotulus – Puthz 1972d: 107. — Shavrin & Puthz 2007: 120.

Stenus (Nestus) illotulus – Ryvkin 1987: 159.

Material examined

RUSSIA: 1 ♀, Tuva, Todjenskiy District, Azas Nature Reserve, near cordon at Azas Lake , 940 m a.s.l., left bank of channel: sedge-gramineous bog (+ Trollius sp. etc.) with tussocks, 15 Jun. 1991, A.B. Ryvkin leg. ( AR) ; 3 ♂♂, 3 ♀♀, Buryatia, Okinskiy District, 1900 m, Il’chir Lake , 21–23 Aug 2007, A.V. Shavrin leg., <det. V. Puthz, 2008> ( AR, ASh) ; 2 ♂♂, Amur Area, Zeyskiy Nature Reserve, ‘34th km’ cordon, Gulik River valley, in litter, 23 Jun. 1978, V.V. Belov & S.A. Kurbatov leg. ( AR) ; 1 ♂, Amur Area, Selemdzhinskiy District, Byssa River 10 km below ‘ Tyoplyi Klyuch’ spa, 290 m a.s.l., leaf litter among tussocks with Spiraea sp., Calamagrostis sp., Carex spp., etc. in high flood-plain, 3 Jun. 2007, E.M. Veselova & A.B. Ryvkin leg. ( AR) ; 1 ♂, 1 ♀, Amur Area, Selemdzhinskiy District, Byssa River basin, bottom part of mountainside NW of ‘ Tyoplyi Klyuch’ spa, 370 m a.s.l., litter under Alnus sp. with Spiraea sp., undergrowth of Betula platyphylla , Trientalis europaea , Poaceae gen. spp., Rubus arcticus, etc., 22 Jun. 2007, E.M. Veselova & A.B. Ryvkin leg. ( AR) ; 1 ♂, 1 ♀, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve, Selemdzha River basin, 2 km NE of Dvadtsatikha cordon, open swamp near lakeside: plant debris and sparse mosses among tussocks with Carex spp., Poaceae gen. sp., Salix spp., etc., 9 Aug. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Mazanovskiy District, Nora River mouth, 210 m a.s.l., mosses and leaf litter on natural levee and in flood-plain forest with Alnus sp., Salix spp., Padus sp., ferns, Poaceae gen. spp., Carex spp., Smilacina davurica , etc., 6 Aug. 2006, E.M. Veselova & A.B. Ryvkin leg. ( AR) ; 2 ♀♀, Amur Area, 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 Aug. 2004, A.B. Ryvkin leg. ( AR) ; 5 ♀♀, Amur Area, Mazanovskiy District, Nora River basin, Sorokavyorstnaya channel, upper reaches of Zolotoy Rill , 270 m a.s.l., mosses and plant debris along edge of slope swamp near mountain crest: Eriophorum sp., Chamaedaphne calyculata , Vaccinium uliginosum , Ledum palustre , Rhododendron sp., Betula ? fruticosa , B. platyphylla , Alnus sp., Oxycoccus sp., etc., 28 Jul. 2006, E.M. Veselova & A.B. Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Mazanovskiy District, Nora River basin, Sorokavyorstnaya channel, foot of S slope of Sosnovaya Mountain , 215 m a.s.l., flood-plain birch forest with Betula platyphylla , Alnus sp., Padus sp., tussocks of Carex spp. and Poaceae gen. spp., Pteridium aquilinum , Convallaria keiskei , Thalictrum sp., Equisetum sylvaticum , etc., 29 Jul. 2006, E.M. Veselova & A.B. Ryvkin leg. ( LH) ; 3 ♂♂, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve, Nora River, 0.5 km up-stream of Gryashchinskaya Mt., mosses and leaf litter under Betula platyphylla and Larix gmelinii with Calamagrostis sp., Equisetum sylvaticum , E. pratense , Maianthemum bifolium , Polygonatum sp., etc. in burnt forest along river bank, 27 Aug. 2004, A.B. Ryvkin leg. ( ShIN) ; 2 ♂♂, 1 ♀, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve, Nora River basin, 1.5 km up-stream of Gryashchinskaya Mt., mosses and plant debris on open swamp along lake side: tussocks of Carex spp. and Poaceae with Sphagnum ? girgensohnii, Sph. ? angustifolium, Sph. ? magellanicum , Sph. squarrosum, Sph. spp., Chamaedaphne calyculata , Vaccinium uliginosum , sparse Ledum palustre , Salix sp., Betula ? fruticosa , etc., 24 Aug. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve, Nora River basin near Meunskiy cordon, mosses and plant debris among Carex spp. & Poaceae with Comarum palustre , Sphagnum squarrosum, Sph. spp., Aulacomnium sp. and other true mosses near side of flood-plain lake and swampy road, 13 Aug. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve, Nora River basin near Meunskiy cordon, mosses and plant debris at flood-plain of a rill: Alnus sp., Carex spp., Poaceae gen. sp., Trientalis europaea , Convallaria keiskei , Sphagnum squarrosum, Sph. spp., Hypnum sp., etc., 15 Aug. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♀, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin, 1.5 km NW of Burunda cordon, plant debris among tussocks of Carex spp. under sparse Alnus sp. with young growth of Larix gmelinii along rill bank near road, 17 Sep. 2004, A.B. Ryvkin leg. ( AR) ; 2 ♀♀, same locality and biotope, 18 Sep. 2004, A.B.Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin, 0.5–1 km NW of Burunda cordon, plant debris and small true mosses among Carex spp. & Poaceae (+sweeping) along rill bank, 12 Sep. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♂, same locality, mosses and plant debris among sedge tussocks with Spiraea sp.,? Aulacomnium sp., Sphagnum squarrosum, Sph. ? girgensohnii , small true mosses, etc., 5 Oct. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♂, Amur Area, Selemdzhinskiy District, Norskiy Nature Reserve (buffer zone), Burunda River basin, 1.5–2 km SE of Burunda cordon, mosses and leaf litter under Betula platyphylla with Ledum palustre , Chamaedaphne calyculata , Salix sp., Sphagnum spp., Hypnum sp., Poaceae gen. sp., etc., 6 Oct. 2004, A.B. Ryvkin leg. ( AR) ; 1 ♀, Amur Area, Selemdzhinskiy District, Norskiy Reserve , 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., 8 Oct. 2008, A.B. Ryvkin leg. ( AR) ; 1 ♀, Khabarovsk Territory, Verkhnebureinskiy District, lower reaches of Verkhniy Mel’gin River near 1st rapid, 300–350 m a.s.l., moss and litter on steep rocky SE slope with Betula platyphylla , Abies nephrolepis , Larix gmelinii , Acer ukurunduense , Rhododendron dauricum , Poaceae gen. spp., Carex sp., Vaccinium vitis-idaea , Linnaea borealis , Maianthemum bifolium , Trientalis europaea , Ledum sp., Alnus sp., ferns, Equisetum pratense , Hylocomium splendens , Sphagnum girgensohnii , Dicranum sp., Ptilium crista-castrensis , Polytrichum commune , etc., 20 Aug. 2009, A.B. Ryvkin leg. ( AR) ; 1 ♂, 1 ♀, Khabarovsk Territory, Verkhnebureinskiy District, Ust’- Urgal Nature Park (project), near Semicha River mouth, SE side of old channel, 280 m a.s.l., leaf litter and moss in birch forest with Larix gmelinii , Ledum sp., Vaccinium vitis-idaea , Poaceae gen. spp., Carex sp. by edge of larch- Ledum sparse forest, 29 Aug. 2009, A.B. Ryvkin leg. ( AR) .

Remarks

This very nice and distinctive species was described based only on the male holotype, from Southern Cis-Baikalia (‘Südsibirien: Tunkun-Sajan’). In the same year, Puthz (1972c), based on two specimens deposited in the Helsinki Museum, reported S. illotulus for the N Lena basin: ‘Shigansk [=Zhigansk] und <…> Ust-Aldan’. The latter specimen is a male, and the sketch of the aedeagus that I recently received from Dr. Puthz proves that it is unlikely that it belongs to S. illotulus . I think it necessary to accumulate additional material from the N Lena basin to give an adequate interpretation of these specimens. Shavrin & Puthz (2007) provided records for the Irkutsk Area (I have seen the specimen) and SE Buryatia; the mention of the Krasnoyarsk Territory and N Mongolia in distributional remarks by the named authors was not accompanied by a reference to any material. The remark concerning the Krasnoyarsk Territory was a misprint (A. Shavrin pers. comm.). The remark for N Mongolia is based on 2 ♂♂, 6 ♀♀, Mongolia, Terelji, 8–12 Jul. 1996, T. Ito leg. (GMR, TI, VP) (V. Puthz pers. comm.). The new data cited above from the Khabarovsk Territory, Amur Area, and Tuva Republic widen the known range of S. illotulus as regards both its SW and its E limits. Stenus illotulus , as well as S. raddei , inhabits moss and leaf litter in habitats moist to moderately wet, but is as a rule less abundant than the latter in those communities.

Figures

Fig. 2. – A–B: Stenus (Nestus) raddei Ryvkin, 1987: ♂ (Russia: Magadan Area: Sibit-Tyhellakh). A. Aedeagus, ventral view. B. Apical part of aedeagus, ventral view. – C–D: S. (N.) illotulus Puthz, 1972: ♂ (Russia: Amur Area: Zeyskiy Nature Reserve). C. Aedeagus, ventral view. D. Apical part of aedeagus, ventral view. Right paramere removed. – E. S. (N.) confusus J. Sahlberg, 1876: ♂ (Russia: Kalinin Area: Putilovo). Aedeagus, ventral view. – Scales = 0.1 mm.