Review of Armored Searobins of the Genus Peristedion (Teleostei: Peristediidae) in Japanese Waters Author Ono, Makoto Graduate School of Fisheries Sciences, Hokkaido University, 3 - 1 - 1 Minato-cho, Hakodate, Hokkaido, 041 - 8611 Japan Author Kawai, Toshio Fisheries Science Center, Hokkaido University Museum, 3 - 1 - 1 Minato-cho, Hakodate, Hokkaido, 041 - 8611 Japan E-mail: kawai @ museum. hokudai. ac. jp & Corresponding author kawai@museum.hokudai.ac.jp text Species Diversity 2014 2014-11-25 19 117 131 journal article 10.12782/sd.19.2.117 2189-7301 5737323 Key to Japanese species of the genus Peristedion 1. Rostral projection spatulate ( Fig. 3B ); anterior edge of fourth sensory pore of rostral projection posterior to anterior edge of premaxilla ( Fig. 2B ) ........ P.liorhynchus – Rostral projection triangular ( Fig. 3A, C, D ); anterior edge of fourth sensory pore of rostral projection anterior to anterior edge of premaxilla ( Fig. 2A, C, D ) ....... 2 2. Branches on filamentous barbel 13–20; total chin barbels 13–16; perifacial rim smooth and straight ( Fig. 2A ) ...................................................................... P. orientale – Branches on filamentous barbel 21–34; total chin barbels 17–26; perifacial rim prominent starting near anterior margin of lower jaw ( Fig. 2C, D ) .......................... 3 3. Rostral projection broadly triangular with straight margin on medial side at base ( Fig. 2C ); rostral projection width 12.1–13.3% HL ......................... P. amblygenys – Rostral projection narrowly triangular with rounded margin on medial side at base ( Fig. 2D ); rostral projection width 8.6–12.3% HL .............................. P. nierstraszi