Smooth toadfish

With a total adult length of anywhere from 3 to 16 cm (1 1⁄8–6 1⁄4 in), the smooth toadfish has an elongate body with a rounded back and flattened belly. The body narrows posteriorly to the slender tail, and its fins are all elongate and rounded. The dorsal fin has 9 to 11 rays. The pectoral fin has 15 to 18 rays, the first of which is very short. It arises well below the level of the eye. The anal fin has 7–9 rays and caudal fin has 11. The smooth toadfish has a small mouth with thin lips at its apex and a tiny chin. The round eyes are adnate (unable to rotate), their upper border is level with the profile of the back and the lower border is well above the mouth. In a slightly depressed area just in front of the eyes are two small nipple-shaped structures (papillae) that are the nasal organs. The openings face to the rear of the fish and are closed by flaps attached to the walls closest to the fish's midline. The first pharyngobranchial gill arch is elongated and narrow with many tiny teeth. The smooth toadfish has tiny spines that are entirely within the skin layer; these run along its back from the nasal organs almost to the dorsal fin, and along its sides from the eye to the pectoral fine, and along its underparts from behind its mouth to its vent. The skin is smooth even when the fish is fully inflated. It swallows water or air via a flap in its throat to swell itself up. The base colour of the upperparts is pale tan to yellow-green, heavily marked with irregular brown spots in a reticulated pattern, and several broad dark brown bands, including ones between the eyes, between the pectoral fins and at the level of the dorsal fin. Reminiscent of a leopard's spots, the reticulated pattern continues on the upper lateral side along the body of the fish, becoming silver-white on the lower lateral parts. The chin and belly are white. The fins have a faint yellow-orange tinge, more noticeably in the tail fin. Fieldwork in Sydney waters found females to be larger and heavier than males. Smooth toadfish grow steadily larger as they grow older, with one 16 cm (6 1⁄4 in) long individual calculated to be 13 years old from examination of its otoliths. Their gonads develop when they reach a total length of about 7–8 cm (2 3⁄4–3 1⁄8 in). The smooth toadfish can be distinguished from the otherwise similar common toadfish by its lack of spines and its larger- and bolder-patterned markings on its upperparts.