Crocus Clam, Boring Giant Clam

"Tridacna Crocea are beautiful giant clams with a variety of patterns and color mixtures. They have fascinating designs in blues, purples, yellows, greens, browns, golds, and oranges. The mantle is usually decorated with iridescent blue, yellow, or green blotches, spots or lines. With its maximum length being only 6 to 9 inches (15.2 to 22.9 cm), T. crocea is also the smallest of the Tridacna clams.

Though often simply referred to as a 'Crocea', the Crocea Clam is also known by a number of common names including Crocus Clam and the Saffron Colored Giant clam. Because it is a Boring Clam, burrowing into boulders and coral heads, it is also called the Boring Giant Clam. "

Source: http://animal-world.com/Aquarium-Coral-Reefs/Crocea-Clams