Wilson the Wanderer

Meet Wilson:

(Extra points if you catch both the references in his name.)

Wilson is a blue tuxedo urchin (mespilia globulus), a short-spined sea urchin that eats algae and, occasionally, seaweed. Tuxedo urchins come in blue, black, and red varieties, all of which have alternating colored bands and patches of short (but potent) spines.

In the wild, tuxedo urchins are found throughout the Western Pacific and Indian oceans. They live on reefs and rocky areas where algaes grow. Most prefer to eat coralline algae (a hard, purple, encrusting algae that lives on mature reefs), and Wilson is no exception. He used to consider seaweed an acceptable substitute (as the picture shows) but since he reached his adult size (3″ in diameter) he pretty much sticks to chewing on rocks.

Urchins have unique and formidable teeth which form a star-shaped pattern in the urchin’s mouth. (Interesting fact: the urchin’s teeth are known as “Aristotle’s Lantern” because of their similarity to hand lanterns carried in Aristotle’s day.) The teeth never stop growing, and the act of chewing sharpens them continually.

Like all urchins, Wilson’s mouth is located on the underside of his body. (The round opening you see on top of him is the other “business end” – and yes, he poops upward.)

Wilson has a tendency to pick up and carry loose objects, sometimes for days or even weeks at a time.

In the wild, this serves as a form of camouflage.

In the home aquarium, it’s a never-ending source of entertainment, particularly since he doesn’t distinguish between organic and inorganic objects.

Have you ever seen an urchin? If you do – be careful! Even the short-spined varieties can deliver a painful – and sometimes venomous – sting.