A common toad fish (tetractenos hamiltoni) looking more dignified than common when viewed in its natural environment.

Commonly caught in shallow sandy estuaries this little fish (5-15 cm) has a prickly leathery skin, grunts when out of the water and has teeth that can cut a fish hook. This fish shound NEVER be eaten. Parts of it are extremely poisonous. For some interesting reading on its toxicity see this document from the Medical Journal of Australia website. (Especially the extract from Captain Cook's journal, page 4)

A smaller version of this image is on the lady reef dive site page.