Tridacna sp. [cf noae]

In the Ningaloo region of Western Australia, 'T. noae' are recorded as Tridacna sp.[cf noae] due to the frequent absence of white-bordered spots on the mantle compared to other populations of this species. The Ningaloo population show high variability in mantle ornamentation and individuals may present with any combination of the following: white-bordered oval spots, a rim of generally discontinuous dark spots (hyaline organs) and raised papillae.

Shell is asymmetrical and partially embedded with pointed processes on the upper shell margin and raised ridges that feature prominent scales. The shell is indistinguishable from T. maxima, which may not occur in the Ningaloo region, however it differs from T. crocea, another burrowing species, which has rounded processes on upper margin, is smaller, and embeds fully in reef substrate. T. squamosa shares a similar range and habitat, but does not embed in the substrate and has a symmetrical shell with rounded processes on the upper margin.