Juvenile Tridacna costata and squamosa

Description:

Warning The original file has a large number of pixels and when opened at full resolution, may either not load properly or cause your browser to freeze. These problems can be avoided by use of the ZoomViewer.: Interactive large-image-viewer (non-Flash). Description: English: Tridacna costata Richter, Roa-Quiaoit, Jantzen, Al-Zibdah, Kochzius, 2008. Juvenile shell, 90 mm. Old shell, still grayish after cleaning. The lemon yellow shell below is Tridacna squamosa Lamarck, 1819. Juvenile shell, 70 mm without the protruding scales. Acquired around 1977. This work shows the differences between T. costata and T. squamosa: The front and backview of T. costata is in the shape of a droplet, widest at the byssal orifice. The front and backview of T. squamosa is oval shaped and nearly has left-right symmetry. T. costata has five central ridges, while T. squamosa has four. Also note that the spacing between the upright scales is smaller for T. costata. Date: 23 February 2011. Source: Own work. Author: MerlinCharon.