A 2017 study, drawing on the 2013 edition of Fishes of Japan (日本産魚類検索), edited by
Nakabo Tetsuji [
ja], and the 2001 edition of Freshwater Fishes of Japan (日本の淡水魚), edited by
Kawanabe Hiroya [
ja], and including only those that "largely spend their lives in freshwater or
diadromous fishes that reproduce in freshwater", but excluding those of the
Ryūkyū Islands, lists some one hundred and eighty-one taxa, thirty-one of which, though they may have an established Japanese name and be written about at some length, are yet to be
formally described, and as yet have no
scientific binomial or
trinomial.[7] As for the inland water fishes of the Ryūkyūs, a 2014 checklist detailed some 678 species, in 110
families, and 27
orders, but of these, 334 are primarily marine species "but accidentally migrate to inland waters", with a further 229 estuarine species (143 residential, 86 peripheral), 59 species being fluvial, and 56 diadromous.[8] In addition, it is noted that most of the fluvial species on
Okinawa Island are
alien.[8] A 1998 study, drawing on earlier editions of the above works by Nakabo and Kawanabe, lists 211 taxa nationwide, in 35 families, and 15 orders, comprising 134 fluvial and lacustrine fishes (63%) and 77 diadromous fishes (37%), including 88 endemics (41%) and 23 exotics (11%).[9]
As of the 7 July 2021 update, Eschmeyer's
Catalog of Fishes returns three hundred and forty species records for freshwater fishes of Japan, excluding
synonyms unless valid as a subspecies, and four hundred and thirty-two brackish water fishes, one hundred and ninety-two records representing those found in both systems, one hundred and fifty-six of which are also found in marine environments.[10]
Incorporating new species
described and other taxonomic changes since the 2013 third edition of Fishes of Japan (日本産魚類検索), edited by
Nakabo Tetsuji [
ja], Motomura Hiroyuki (本村浩之) of the
Kagoshima University Museum published in 2020 List of Japan's All Fish Species (日本産魚類全種目録), subtitled "Current standard Japanese and scientific names of all fish species recorded from Japanese waters"; regular
open access updates are published, that of July 2021 detailing some 4,611 species.[12][13]
^Ministry of the Environment, ed. (2014). レッドデータブック 2014 Vol. 4 汽水・淡水魚類 [Threatened Wildlife of Japan Red Data Book 2014: Pisces — Brackish and Fresh Water Fishes] (in Japanese). Gyōsei Corporation.
ISBN978-4-324-09898-1.
^Yuma, Masahide; Nagata, Yoshikazu (1998). "Distribution of the freshwater fishes of Japan: an historical overview". In Yuma, Masahide; Nakamura, Izumi; Fausch, Kurt D. (eds.). Fish biology in Japan: an anthology in honour of Hiroya Kawanabe. Developments in environmental biology of fishes, vol. 18.
Springer. pp. 97–124.
doi:
10.1007/978-94-015-9016-7_6.
ISBN978-94-015-9016-7.