First specimen-based records of Canthidermis macrolepis (tetraodontiformes: Balistidae) from the pacific ocean and comparisons with C. maculata

Abstract

Canthidermis macrolepis (Boulenger, 1888) is newly recorded from Japan and Micronesia on the basis of nine specimens (206.9-349.8 mm SL), having been previously reported from the northwestern Indian Ocean and northern South China Sea (the latter based solely on DNA barcoding). The species is probably widespread throughout the Indo-West Pacific region but has been confused with Canthidermis maculata (Bloch, 1786). Detailed morphological comparisons of both species resulted in the following differences being recognized between them: numbers of body scale rows [38-41 (modally 40) in C. macrolepis vs. 40-49 (44) in C. maculata], second dorsal-fin rays [25-27 (26) vs. 22-26 (24)], anal-fin rays [22-24 (23) vs. 20-23 (21)] and pectoral-fin rays [14-16 (15) vs. 13-15 (14)]. Sequences of the mitochondrial DNA COI gene determined from the presently-reported specimens of C. macrolepis, which also differed in color from similarly sized C. maculata, having a uniformly grayish body without spots, were also compared with congeners. The Japanese standard name "Bouzu-mongara" is newly proposed for C. macrolepis.