A Revised Taxonomic Account of Ricefish Oryzias (Beloniformes; Adrianichthyidae), in Thailand, Indonesia and Japan

Abstract

A taxonomic account of Oryzias minutillus, O. mekongensis, O. dancena, and O. javanicus from Thailand, O. celebensis from Indonesia and O. latipes from Japan are redescribed. Six distinct species are recognized. Keys, descriptions and illustrations of the species are presented. Morphological differences between and within all six species are clarified. Twenty-two morphometric characters and ten meristic characters were examined, and 14 morphometric and nine meristic characters were found to differ amongst the six species. Anal-fin ray numbers of O. cellebensis, O. javanicus, O. dancena, O. minutillus, O. latipes and O. mekongensis were 22, 23, 24, 19, 18 and 15, respectively. These differences suggest that the six species may be reproductively isolated from each other.