Review of Polydactylus species (Perciformes: Polynemidae) characterized by a large black anterior lateral line spot, with descriptions of two new species

Nominal Polydactylus species characterized by a large black spot anteriorly on the lateral line, P. microstomus (Bleeker), P. sextarius mullani (Hora), P. sextarius sextarius (Bloch and Schneider), and P. zophomus Jordan and McGregor, are reviewed. Polydactylus zophomus, with 5 pectoral filaments, is synonymized under P. microstomus, and P. sextarius mullani, with 7 pectoral filaments, is elevated to species level (as P. mullani). Polydactylus microstomus and P. mullani together with P. sextarius (characterized by 6 pectoral filaments) are considered as valid species and redescribed accordingly. Two new species, P. malagasyensis and P. persicus, each with 6 pectoral filaments, collected from the east coast of Africa, including Madagascar and the Persian Gulf, are also described. Polydactylus sextarius and the 2 new species are characterized by 6 pectoral filaments. However, P. sextarius is distinguished from the latter by having lower gill raker counts (mode 28 vs. 31 in the latter) and an atrophied swimbladder (vs. well-developed). Polydactylus malagasyensis differs from P. persicus in having higher pectoral fin ray counts (14 vs. mode 12 in the latter), the palatines inwardly turned anteriorly (vs. straight), and a longer pectoral fin (mean 24% of standard length vs. 19%)