Abstract
Two new species, Cercyon retius sp. nov. and C. primoricus sp. nov., both belonging to the subgenus Clinocercyon, are described from the Russian Far East. A key to the identification of the six known Palearctic species of the subgenus is given. Both new species are illustrated by photographs of habitus and some morphological characters and by drawings of male genitalia. Within the subgenus Clinocercyon, the new species are most similar to C. conjiciens (Walker) and to the two Japanese species (C. aequalis Sharp and C. rubicundus Sharp). With the inclusion of these two new species, the fauna of Cercyon in Russia now comprises 47 species from 5 subgenera.
References
Baranowski, R. (1985) Two new species of Cercyon Leach from boreal Sweden (Coleoptera: Hydrophilidae). Entomologica Scandinavica, 15, 341–347.
Fikáček, M., Angus, R.B., Gentili, E., Jia, F., Minoshima, Y.N., Prokin, A., Przewoźny, M. & Ryndevich, S.K. (2015) Family Hydrophilidae. In: Löbl, I. & Löbl, D (Eds.), Catalogue Palaearctic Coleoptera. Vol. 2/1. Hydrophiloidea – Staphilinoidea. Revised and updated edition. Brill, Leiden-Boston, 37–76.
Hansen, M. (1999) World Catalogue of Insects 2: Hydrophiloidea (s. str.) (Coleoptera). Apollo Books, Stenstrup, 416 pp.
Hansen, M. (2004) Family Hydrophilidae. In: Löbl, I. & Smetana, A. (Eds.), Catalogue Palaearctic Coleoptera. Vol. 2. Hydrophiloidea – Histeroidea – Staphilinoidea. Apollo Books, Stenstrup, 44–68.
Hebauer, F. (1995) Bekante und neue Hydrophiloidea aus Ostsibirien (Col.). Entomologische Nachrichten Berichte, 39, 29–36.
Hebauer, F. & Ryndevich, S.K. (2005) New data on the distribution of Old World Hydrophilidae (Coleoptera: Hydrophilidae). Acta Coleopterologica, 21 (1), 43–51.
Jia, F.-L., Fikáček, M. & Ryndevich, S.K. (2011) Taxonomic notes on Chinese Cercyon: description of a new species, new synonyms, and additional faunistic records (Coleoptera: Hydrophilidae: Sphaeridiinae). Zootaxa, 3090, 41–56
Ôhara, M. & Jia, F.-L. (2006) Terrestrial Hydrophilid Beetles of the Kuril Archipelago. Biodiversity and Biogeography of the Kurri Islands and Sakhalin 2, 129–150.
Ryndevich, S.K. (1998) New species of beetles of the genus Cercyon (Coleoptera: Hydrophilidae) from Russian Far East Pakistan Journal of Zoology, 30 (1), 59–60.
Ryndevich, S.K. (2001) On identification of species of the Cercyon dux group (Coleoptera: Hydrophilidae) Zoosysematica Rossica, 10 (1), 79–83.
Ryndevich, S.K. (2004) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. I. Subgenus Cercyon (s. str.) Leach, 1817. Cercyon lateralis–group (Coleoptera: Hydrophlidae) Annales Universitatis Mariae Curie-Sklodowska (Section C), 59, 1–13.
Ryndevich, S.K. (2006) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. II. Subgenus Cercyon Leach, 1817. Cercyon olibrus and C. rotundulus groups (Coleoptera: Hydrophilidae). Zoosystematica Rossica, 15 (2), 311–314.
Ryndevich, S.K. (2007) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. III. Subgenera Clinocercyon Orchymont, 1942 and Conocercyon Hebauer, 2003 (Coleoptera: Hydrophilidae). Zoosystematica Rossia, 16 (2), 315–320.
Ryndevich, S.K. (2008) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. IV. The subgenera Paracycreon Orchymont, 1924 and Dicytocercyon Ganglbauer, 1904 (Coleoptera: Hydrophilidae). Zoosystematica Rossica, 17 (2), 89–97.
Ryndevich, S.K. (2011) New data on Holarctic and Oriental Spercheidae and Hydrophilidae (Coleoptera: Hydrophiloidea). Euroasian Entomological Journal, 10 (3), 337–340.
Ryndevich, S.K. & Hebauer, F. (2010) Review of species of the genus Cercyon Leach, 1817 of Russia and adjacent regions. V. Subgenus Cercyon (s.str.) Leach, 1817. Cercyon nigriceps–group (Coleoptera: Hydrophilidae). Zoosystematica Rossica, 19 (2), 330–340.
Shatrovskiy, A.G. (1992) New and little known Hydrophiloidea (Coleoptera) from Southern Primorye territory and adjacent regions. Entomological Review, 71 (2), 359–371.
Short, A.E.Z. & Fikáček, M. (2011) World catalogue of the Hydrophiloidea (Coleoptera): additions and corrections II (2006–2010). Acta Entomologica Musei Nationalis Pragae, 51 (1), 83–122.