Hi all. I have two specimens of spondylus taken from a jetty pillar in 5m of water while diving. They have a similar dorsum maroon coloring, and hence they might be color variations of the same species.

Specimen 1: http://www.shellnutx.com/gallery/v/wei/singapore_collection/Spondylidae/Spondylidae_Spondylus_sp1.JPG.html

Specimen 2: http://www.shellnutx.com/gallery/v/wei/singapore_collection/Spondylidae/Spondylidae_Spondylus_sp1_var.JPG.html

Any suggestions are welcome. Thanks in advance.