Redescriptions of two western Pacific triplefins (Perciformes: Tripterygiidae), Enneapterygius fuscoventer and E. howensis

Two western Pacific triplefins, Enneapterygius fuscoventer Fricke 1997 and E. howensis Fricke 1997 (Perciformes: Tripterygiidae), are similar to each other in sharing 15–19 (usually 17) notched lateral-line scales and the mandibular pore formula 3–5 + 1 + 3–5 (usually 4 + 1 + 4), in addition to similar coloration, viz. body with four vertical bands, the first and second forked ventrally, dorsal-fin membrane semi-transparent, anal fin entirely blackish, and caudal fin blackish with a semi-transparent margin. These species have previously been known only from preserved specimens. Examination of additional specimens plus color photographs of males and females of both species when fresh, and comparisons with type specimens resulted in several features, including coloration and counts of second dorsal-fin spines, anal-fin soft rays, pored lateral-line scales and longitudinal scale rows, being regarded as new diagnostic characters. Enneapterygius fuscoventer and E. howensis have been newly recorded from southern Japan and coastal eastern Australia, respectively.