A northward range extension of Thysanophrys papillaris (Actinopterygii: Scorpaeniformes: Platycephalidae) to Taiwan

Abstract

The smallknob flathead, Thysanophrys papillaris Imamura et Knapp, 1999, is redescribed based on six specimens collected from southern Taiwan, which constitutes a northward range extension of the species [previously recorded from the Andaman, Timor, and Arafura seas (eastern Indian Ocean), and Nha Trang, Vietnam (western Pacific Ocean)]. Thysanophrys papillaris is distinguished from all congeneric species in having a combination of 11 second dorsal-fin rays, 12 anal-fin rays, 58–75 scale rows below the lateral line (slanting downward and forward), a longer snout (snout length / orbital diameter ratio 1.1–1.3), 1 or 2 small papillae on the eye, the upper iris lappet with short branches, a single preorbital spine and 3–5 suborbital spines. Previously suggested intraspecific variation in the number of eye papillae is confirmed.