Satoshi Kamitani

Species diversity and community structure of rove beetles (Coleoptera: Staphylinidae) attracted to dung of sika deer in coniferous forests of southwest Japan

Insect communities of mammal dung have been known as excellent model ecosystems for scientific study. Ecological surveys of diversity and seasonal patterns of coprophilous rove beetles in relation to wild mammals have rarely been conducted, although the high potential species diversity and abundance of the rove beetles are known. In order to investigate biodiversity of these beetles, we analyzed species composition, abundance, feeding guild and seasonality of rove beetles that were attracted to sika deer Cervus nippon dung by using dung‐baited pitfall traps for a 1.5‐year study in two plantations (cypress, cedar) and one secondary natural forest (pine) in Fukuoka Prefecture, southwest Japan. Consequently, saprophagous Anotylus sp. (Oxytelinae) was dominant in all forests. Analyses of feeding guild structure showed the number of individuals were dominated by saprophagous beetles, but the number of species were dominated by predatory beetles. Seasonal effects suggested that the species richness and abundance of rove beetles are possibly regulated by scarabaeoid dung beetles. These findings feature one example of a coprophilous rove beetle community.

Sexual difference in antennal sensilla abundance, density and size in Callosobruchus rhodesianus (Coleoptera: Chrysomelidae: Bruchinae)

Sexual difference in antennal sensilla size and per area density has rarely been studied in insects. The bruchine seed beetle Callosobruchus rhodesianus (Pic) (Coleoptera: Chrysomelidae: Bruchinae) is distributed over Central and Southern Africa and is a pest of stored legume seeds, especially cowpeas Vigna unguiculata. Here, we study the type, abundance, morphology and per area density of antennal sensilla on each antennal segment and their sexual differences in C. rhodesianus. The antennae of normal individuals consist of the scape, pedicel and nine flagellomeres as in other congeneric species. Sizes of most antennomeres are larger in males than in females. We observed the following eight different types of antennal sensilla: sensilla trichodea types 1 and 2 (ST1, ST2), sensillacavitae (SCa), sensilla chaetica (SC), sensilla basiconica types 1, 2 and 3 (SB1, SB2, SB3) and Böhm bristles (BB). The SCa is found on all antennomeres unlike in congeners (C. chinensis and C. maculatus). The ST1, the most numerous and longest antennal sensilla type, is denser and thinner in females than in males but more abundant in males than in females. Since the ST1 is considered to serve as a chemoreceptor, the sexual difference in the ST1 may benefit males in searching for mates.

Taxonomic study of the genus Scaphoideus Uhler (Hemiptera, Cicadellidae, Deltocephalinae) from Japan

The Japanese species of the genus Scaphoideus are revised. Eight species are recognized from Japan, including four new species: S. ryukyuensis sp. nov. from the Ryukyus, S. pristiophorus sp. nov. from Honshu and Kyushu, S. aurantius sp. nov. from the Ryukyus and S. brevistylus sp. nov. from Honshu, Kyushu and the Ryukyus.