The author previously reported that a bat fly Penicillidia jenynsii inhabits exclusively the body fur of a bat Miniopterus fuliginous, and that this bat fly tends to approach and burrow into the fur of M. fuliginous and avoids the fur of a greater horseshoe bat Rhinolophus ferrumequinum and a Japanese large-footed bat Miniopterus macrodactylus. In this study, the author attempted to determine whether P. jenynsii discriminates the fur of M. fuliginous from that of other bat species by chemical substances emitted from their fur. Tissue paper was rubbed repeatedly against the body fur of M. fuliginous or R. ferrumequinum. Then the M. fuliginous fur-rubbed paper and R. ferrumequinum fur-rubbed paper were placed in an experimental box side by side and bat flies were released in the box to see how they behave. The bat flies approached and burrowed much more frequently into M. fuliginous fur-rubbed paper than into R. ferrumequinum fur-rubbed paper. In addition to this experiment, two comparisons were made. The structures of the fur surfaces of the two bat species were compared using an electron microscope . Clear differences were observed. Volatile chemical substances from the fur of the two bat species were compared by gas chromatography. It was clarified that nonanal and hexanal were emitted more from the fur of M. fuliginous than from that of R. ferrumequinum.

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Dryopteris caudipinna Nakai was newly recorded from Hiroshima Prefecture, Japan. Though this rather rare diploid sexual fern has previously been known from Japan and South Korea, most factors determining its distribution remain unclear. Population of D. caudipinna was restricted to the southern part of Ujina Island, where rather wet humus rich evergreen forest floors were observed. The number of individuals was estimated to be approximately 500 or higher. This report also describes new record of this fern from a Seto Inland Sea region.

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Larval transport by adult Lasius morisitai was observed in nests of L. morisitai in a single tree of Abies sachalinensis in Obihiro, Hokkaido, Japan. Larval transport was observed on 21 June and from 29 September to 7 October 2022 during the day (8:00-11:00am and around 3:30pm), just after sunset (around 5:00pm), and at night (8:00-10:00pm).

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Cleaning behaviors of the common carp, Cyprinus carpio, on the grass carp, Ctenopharyngodon idellus, in a large aquarium tank were described for the first time. When a young common carp pecked at the body of an adult grass carp, the grass carp stopped swimming, raised its head slightly upward, and tilted its body at an angle. These actions of the grass carp were supposedly for requesting cleaning from the common carp. This was a rare case of cleaning behaviors among freshwater fishes.

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