Today I thought it would be cool to gather up close ups of various starfish and offer a perspective that most folks don't usually see.
Colorful and beautiful. Yes! But also, functional. A lot of the mouth you see below were photographs of sea stars from the tropical Pacific and Indian Oceans. The tropics are a tough place for some animals with many crabs and fish always willing to take a peck of tissue or a tube foot for dinner.
A great many of the sea stars in these areas come with protection- a LOT of it. Spines and armor adorn the soft, vulnerable areas of these sea stars. Those spines on the tube foot grooves you see below can actually interlace and close up the grooves to protect the vulnerable tube feet from being pecked at by fish, crustaceans or what-have you...
Here's another shot of Halityle from another angle. Plus you can see the tiny shrimp!
From a "cushion star" probably Halityle.. (note the shrimp!)
From Fromia sp. Note how all of the spines interlace and protect the tube foot groove
Another oreasterid that I'm unsure of the species-probably Pentaceraster. A nice perspective. Notice the tiny Periclemenes commensal shrimp!
Photo by Tahiticed
Here's a tropical goniasterid that lives in the deep-sea Atlantic-A weird animal called Gilbertaster that I worked on a few years ago.. See all of those elongate "lip" like things? Bivalve pedicellariae! See here for some more on pedicellariae.
Could these be for further defense?
A nice pic of the mouth/oral side of Patiriella calcar from south Australia/Tasmania. Note the multiple oral plates projecting into the mouth..