New Genus and Species of Pufferfish (Tetraodontidae) from Norfolk Island, Southwest Pacific

A new genus and species of tetraodontid pufferfish (Pelagocephalus coheni) is described, based on a specimen presumably collected by a white tern at Norfolk Island, southwest Pacific. The new species is perhaps endemic to the Norfolk Island region in an offshore semi-pelagic habitat. It differs from all other tetraodontid plectognath fishes in two respects by the following: (1) the ventral portion of the parasphenoid under the orbit is divided into a pair of ventrolaterally directed flanges forming a thin palate over the rear of the oral cavity, rather than being a single vertical plate in the midline as in other pufferfishes; (2) the nasal apparatus is an open, flat, relatively unornamented disk flush with the surface of the surrounding skin, rather than being a short to long tube with one or two nostrils, a paired or single tentacle, or an open large elaborate cup as in other pufferfishes.