A new species of Nogunius Jałoszyński in Japan (Coleoptera: Staphylinidae: Scydmaeninae)

The genus Nogunius Jałoszyński was proposed to accommodate four species distributed exclusively in Japan: N. sokani Jałoszyński (Okinawa Island), N. aogashimanus Jałoszyński (Aogashima, Izu Islands), N. kerri Jałoszyński (Ishigaki Island), and N. fukuuzanus Jałoszyński (Okinawa Island). A female of an undescribed species collected in mainland Japan, on Shikoku, was also recorded. In the present paper we provide evidence that this interesting and apparently very rare genus occurs also on Kyushu. Nogunius sagaensis sp. n. is described, based on a single male collected in Saga Prefecture, NW Kyushu. Diagnostic characters of all nominal species are compared, and a distribution of Nogunius is summarized.

Himaloconnus Franz and Nogunius gen. n. of Japan (Coleoptera: Staphylinidae: Scydmaeninae)

Two genera of Euconnus-like Stenichnini are reported to occur in Japan: Himaloconnus Franz, 1979 and Nogunius gen. n. Specimens of Himaloconnus collected on islands of the Ryukyu archipelago are identified as H. klapperichianus (Franz), previously known to inhabit Taiwan, but morphological differences were found among disjunctive populations and in consequence three new subspecies are proposed: H. klapperichianus yaeyamanus ssp. n. (Yaeyama Islands), H. klapperichianus amamianus ssp. n. (Amami-Ôshima), and H. klapperichianus okinawanus ssp. n. (Okinawa Island). Morphological structures of Japanese Himaloconnus are illustrated in detail and the diagnosis of this genus is emended, to exclude variable characters. Nogunius gen. n. is established to accommodate four species known only from Japan: N. sokani sp. n. (Okinawa Island), N. aogashimanus sp. n. (Aogashima, Izu Islands), N. kerri sp. n. (Ishigaki Island), and N. fukuuzanus sp. n. (Okinawa Island). Identification key to Japanese genera of Stenichnini is updated.

Sciaphila kozushimensis (Triuridaceae), a new mycoheterotrophic plant from Kozu Island, Izu Islands, Japan, based on morphological and molecular data

A new species of Sciaphila (Triuridaceae), S. kozushimensis Suetsugu, is described from Kozu Island, Izu Islands, Japan. The new species is similar to S. tosaensis in having unisexual flowers (the female towards the base of the rachis), perianth-segments without any appendages and club-shaped style that is as long as or slightly exceeds ovary in the flowering stage. However, it is distinguishable by smaller male flowers, wide and acuminate male perianth segments and somewhat dissimilar perianth segments. An illustration and molecular analysis based on ITS sequences of the new species are provided. A key to the Japanese Sciaphila is also provided for identification of these rare mycoheterotrophic plants.

Natural hybridization patterns between widespread Calanthe discolor (Orchidaceae) and insular Calanthe izu-insularis on the oceanic Izu Islands

Natural hybridization often occurs between insular and widespread species, and investigating these hybridization patterns is important in improving our understanding of the evolution of insular plant species. To this end, we studied the floral morphology and genetic structure of the widespread species Calanthe discolor, the insular closely related species C. izu-insularis and their putative natural hybrids on Honshu Island (mainland) and the Izu Islands (oceanic islands), Japan, using microsatellite markers. Natural hybridization probably occurred on all the investigated Izu Islands in Japan, although C. izu-insularis was morphologically and genetically different from C. discolor. Bumblebees and other relatively large bees are not distributed in the Izu Islands and therefore natural hybridization would have occurred via pollination by relatively small solitary bees that are pollinators of both Calanthe spp. We also showed that in the islands more remote from the mainland, the proportions of insular C. izu-insularis increased and the floral morphologies of both species changed. The results suggested that insular C. izu-insularis evolved on the Izu Islands and the widespread C. discolor adapted to the poor pollinator fauna on oceanic islands.