Information on predators is one of the most important knowledges for biological interpretations of defensive traits possessed by prey animals and for their biodiversity conservation. However, information on natural predators of myriapods have been limited to a few sporadic reports, even on a global scale. Here, I reviewed published accounts of myriapods in Japan along with visual media accumulated on the Internet to compile a list of natural predators of Japanese myriapods. As a result, 202 predator species across 11 classes, preying on 28 species of myriapods belonging to Chilopoda, Diplopoda, and Symphyla, were confirmed. I hope that these findings will encourage biologists and naturalists to record further predation events on myriapods and help create a foundation for ecological research on myriapods.

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Aquatic oligochaetes are important fauna in paddy fields because they suppress annual weeds and enhance nutrient cycling. However, further investigation is needed into the use of aquatic oligochaetes in rice production. Abundance surveys of aquatic oligochaetes in paddy soils have predominantly been conducted by time- and labor-intensive hand-sorting. A wet funnel apparatus is useful for efficiently extracting organisms such as nematodes and enchytraeids from soil. In this study, I first compared the extraction efficiency and counting speed of oligochaetes between handsorting and wet funnel apparatus application. While soil is generally used for the latter, I instead used soil residue separated from the soil. Second, extraction efficiency was compared between two major wet funnel apparatus methods, the Baermann and O’Connor approaches. Mustard powder with the active agent of allyl isothiocyanate was used to extract oligochaetes from the soil. The effectiveness of the addition of this agent, likely repellent for aquatic oligochaetes, in the Baermann apparatus was confirmed in terms of extraction efficiency in the third experiment. Lastly, the feasible storage duration of oligochaetes at three different temperatures after extraction was determined. The Baermann apparatus could effectively extract approximately 90% of oligochaetes and increased the counting speed. Compared with the Baermann apparatus, the O’Connor apparatus slightly increased extraction efficiency in Gleyic Fluvisols and Hydragric Anthrosols; however, adding mustard (0.01 g L－1) did not affect efficiency in this case. Extracted oligochaetes were stored in tap water at 6°C, 10°C, and 15°C. Oligochaete survival rate decreased to approximately 90% after four days, but then remained constant for 2 weeks. This study demonstrates that the wet funnel apparatus technique is a powerful tool for abundance surveys of aquatic oligochaetes in paddy fields.

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A new species, Pseudanisentomon angustum sp. nov., is described from Kagoshima Prefecture, southern Japan. Compared with its congeners, this new species is characterized by the narrowly spatulate sensillum g on the foretarsus. Although similar to P. donan found on Yonaguni Island of the Ryukyu Archipelago, the new species differs by the inner structure of pseudoculus, distinct clypeal apodeme, and shapes of a pair of setae posterior to the pseudoculus, as well as foretarsal sensilla f1 and f2.

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Two new oribatid mite species of the genus Paralycus Womersley, 1944, Paralycus aokii Oshima & Shimano, sp. nov. and Paralycus shibai Oshima & Shimano, sp. nov., are described based on private collection of Professor Minoru Shiba, which he had collected himself. This genus has previously been recorded (no species record) as a taxon under Prostigmata in Japan, but the genus is firstly recorded in Japan by these new species described here. An updated key to the species of the genus Paralycus is provided.

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Seventy-eight geophilomorpha centipedes belonging to the family Schendylidae Cook, 1896 were collected from Mt. Tsuchikura, located in Shiga Prefecture, Honshu, Japan. This species exhibits a callous labrum featuring independent and sturdy teeth. Additionally, the dentate laminae of the mandibles, each with independent and unbranched morphological characters. These characteristics are unique to the genus Momophilus Takakuwa, 1937, within the family Schendylidae, setting it apart from other genera within the same family. Furthermore, this species boasts a diminutive body length of approximately 18 mm, males and females possessing 39 and 41 pairs of legs, respectively. A small carpophagus fossa anterior margin is present on each sternite of the anterior half of the trunk. In females, the last pair of legs is normal, while in males, it bears numerous setae. These characters, in conjunction with the callous labrum and mandibles, were compared to the sole species within the genus Momophilus, namely M. serratus Takakuwa, 1937, revealing marked distinctions. In addition, an obvious disparity in distribution exists between the two species. The species collected from Mt. Tsuchikura are distributed inland in Honshu, while M. serratus is widely distributed along the coastal regions to the west of the Kanto region. Based on these findings, the species collected at Mt. Tsuchikura was classified as previously undescribed and designated as a new species, namely M. drymophilus sp. nov.

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