Introduction
The pufferfish family Tetraodontidae is divisible into two subfamilies, the Tetraodontinae and the Canthigasterinae. The latter subfamily, popularly known as tobies or sharpnose puffers, consists of the marine genus CanthigasterSwainson and the freshwater genus Carinotetraodon Benl. These fishes are differentiated from the Tetraodontinae by a laterally compressed body, elongate pointed snout (only for Canthigaster), erectile ridge of skin middorsally and midventrally, small gill opening, inconspicuous lateral line, 17 vertebrae, and small size. Britz and Kottelat (1999) discuss a synapomorphy for these two genera wherein abdominal vertebrae 1–3 bear independent, unfused, paired parapophyses. In Canthigaster, the hemal spines have posterior lobes that are absent in Carinotetraodon(Britz & Kottelatt, 1999). The bold color patterns of Canthigaster probably serve to advertise their repelling skin toxin (Eger & Starkus 1973).