part of mantle outer mantle 2019-03-04T18:26:20Z BTO:0006277 Besides pigments, the outer mantle of the giant clam Tridacna squamosa has iridophores which consist of small groups of cells containing stacks of tiny platelets .The reflective platelets scatter light of photosynthetically productive wavelengths into the tissue while back-reflecting non-productive wavelength. Thus, the extensible outer mantle is brightly colored. BrendaTissueOBO Marion