Comprehensive DescriptionRead full entry
Ten genera of parrotfishes are recognized (Bellwood, 1994), of which Scarus ZBK is the largest, with over 50 species, and the only one present in all tropical and subtropical oceans. The general morphology is similar for most species of Scarus ZBK , and identification of the Indo-Pacific species of Scarus ZBK can be difficult for preserved specimens that have lost their distinctive life color. Meristic data are of limited value in species identification. Parrotfishes normally have IX, 10 dorsal rays and III, 9 anal rays. The number of pectoral rays of the species of Scarus ZBK vary from 13 to 16, and the count is strongly modal for each species, so it is often helpful. The usual lateral-line scale count of 17-18 + 4-6 is of no diagnostic value, but the number of predorsal scales and the number of rows of scales on the cheek are often useful characters. The gill rakers are small and variable in number within a species. Life colors remain the most important distinctive features in the classification of Scarus ZBK , but sexual dichromatism and the different color of the juvenile stages (Bellwood 1989, Bellwood & Choat 1989) can complicate species identification.
Parrotfishes have extreme variation in color with growth and with sex change (Choat & Randall 1986; Bellwood & Choat 1989), and the juvenile and initial phase color patterns are often difficult to distinguish among species. This has led to a strong focus on the more colorful males as the basis for species descriptions. In the present paper, however, the initial phase coloration is distinctive, with three prominent dark spots on the dorsal, pectoral base, and anal fins, forming the etymological basis for the naming of this new parrotfish species. The authors collected this species independently on the coral reefs of Surin and the Similan Islands of Thailand and the Mentawai Islands, Sumatra.