●新タクサ１
新種トウカイヒメツヤドロムシZaitzeviaria takafumii Hayashi & Yoshitomi 2021の記載。
Hayashi, M. and H. Yoshitomi (2021) A New Species of Zaitzeviaria from Aichi Prefecture, Honshu, Japan (Coleoptera: Elmidae). Japanese Journal of Systematic Entomology, 27 (1): 43–51.
●新タクサ２
チビドロムシ３種の記載：
Byrrhinus satoi Yoshitomi & Hayashi, 2021
Byrrhinus uenoi Yoshitomi & Hayashi, 2021
Byrrhinus tainanensis Yoshitomi & Hayashi, 2021
Yoshitomi, H. and M. Hayashi (2021) Revision of the genus Byrrhinus (Coleoptera, Limnichidae) of Japan and Taiwan. Elytra, Tokyo, New Series, 11 (Supplement): 141–150.
●新タクサ3
ノムラヒメドロムシの新名の提案
Stenelmis amami Yoshitomi & Hayashi, 2021
Kobayashi et al. (2021)でNomuraelmisをStenelmisのシノニムにした結果、ノムラヒメドロムシの学名がアマミミゾドロムシの原記載の学名のホモニムになってしまった。
Yoshitomi, H. and M. Hayashi. 2021. New name for Stenelmis amamiensis (Satô, 1964) (Coleoptera: Elmidae). Japanese Journal of Systematic Entomology 27(2): 269.
●ヒメドロムシ科の系統解析
Kobayashi, T., M. Hayashi, Y. Kamite and T. Sota (2021) Molecular phylogeny of Elmidae (Coleoptera: Byrrhoidea) with a focus on Japanese species: implications for intrafamilial classification. Systematic Entomology, 46: 870–886.
https://onlinelibrary.wiley.com/doi/abs/10.1111/syen.12499
●ヨツモンカタキバゴミムシの食性
Hayashi, M. and S. Sugiura (2021) Shell-breaking predation on gastropods by Badister pictus (Coleoptera, Carabidae) with strikingly asymmetric mandibles. Zookeys, 1044: 815-830.
●水面を活発に移動するイモムシの発見
Hayashi M, Sugiura S. 2021. Active behaviour of terrestrial caterpillars on the water surface. PeerJ 9:e11971 DOI 10.7717/peerj.11971
