Folsomia urumana sp. nov. is described as a new species. The species resembles Folsomia fimetaria (Linnaeus, 1758) with white body, without eyes and 4+4 stout setae on anterior manubrium, but it is clearly different in chaetotaxy from other congeneric species. Axelsonia yinii Huang and Liang, 1992 and Archisotoma megalops (Bagnall, 1939) are reported as new records from Japan. Additional morphological characters, especially in chaetotaxy, of Folsomia bidentata Lee, 1973, Isotomodes fiscus Christiansen and Bellinger, 1980 and Ballistura yasakaensis Tanaka and Niijima, 2007 are newly noted.
To understand the spatiotemporal impacts of earthworms on soil ecosystem functions, further insight into
the phenological patterns of earthworms in various habitats is needed. Especially in landscapes that receive heavy snowfall, the phenological patterns of earthworms is little understood. In this study, we conducted a field investigation of earthworm biomass and density for a whole year (including a winter with heavy snowfall) in a deciduous broad leaf forest and an adjacent evergreen coniferous forest in northern Hokkaido, Japan. The seasonal dynamics of the earthworm abundance were different between the broad leaf and conifer forests. In the broad leaf forest, the density was highest in summer and lowest in winter under 120 cm of snowpack, while there was no seasonal difference in the conifer forest. The different seasonal dynamics in earthworm abundance between the two forest types could contribute to the variations in the temporal patterns of ecosystem functions, such as nitrogen dynamics, which should be tested in future studies.