Spiculed Chiton, Acanthopleura gaimardi
Although its eight shell plates (called valves) are plain, the Spiculed Chiton is distinguished by its broad black-and-brown banded girdle, which consists of numerous, pointed to blunt conical spinelets.
In the Spiculed Chiton, the interior valve and the side area are scuptured with low, inconspicuous granules which occur in ill-defined radial rows. The central area of the valves is featureless, except for a hump in the second-last valve. The end valve is flat and triangular. It's spiculed girdle is very distinctive.
The Spiculed Chiton's shell valves are dull greenish-brown, with lighter grey areas, eroding to almost pure white. Its spiculed girdle is banded black and brown.
The Spiculed Chiton ranges from northern Queensland to southern New South Wales shores.
It occurs out in the open on exposed rock surfaces at mid-tide level and below, and is confined to the tidal region.
A similar looking species from Western Australia is the Hairy Chiton, A. hirtosa.
In the central part of its range, north of Grant's Head, NSW, and along the shores of southern Queensland, this species becomes the most common chiton of the intertidal zone. Because it is restricted to eastern Australia rather than southern shores, it is not described in many other field guides.
Bennett, I. (1987) W. J. Dakin's classic study: Australian Seashores. p. 261. Angus & Robertson
Davey, K. (1998) A photographic guide to Seashore Life of Australia. p. 71. New Holland