Arbacia punctulata

Arbacia punctulata is a species of Arbacia genus of purple-spined sea urchins. Its natural habitat is in the Western Atlantic Ocean. It can be found in shallow water from Massachusetts to Cuba and the Yucatan Peninsula, from Texas to Florida in the Gulf of Mexico, the coast from Panama to French Guiana and in the Lesser Antilles, normally on sandy, rocky, or shelly bottoms.

It is omnivorous, consuming a wide variety of preys. It’s been shown that it is galactolipids, rather than phlorotannins, that act as herbivore deterrents in Fucus vesiculosus against A. punctulata.

Fore more than a century, developmental biologists have valued the sea urchin as an experimental model organism. The eggs are transparent and can be manipulated easily within a research laboratory. Their eggs can be fertilized easily and then develop quickly and synchronously.

The sea urchin embryo has been utilized in establishing the chromosome theory of heredity, the description of centrosomes, parthenogenesis, and fertilization for decades. Research work during the last thirty years established such significant phenomena as stable mRNA and translational control, isolation and characterization of the mitotic apparatus, and the realization that the major structural proteins of the mitotic apparatus are microtubules. Studies regarding the sea urchin provided the first evidence of actin in non-muscle cells.

This species is also a model organism of marine sediments toxicity and sperm study.

Image Caption: Arbacia punctulata Echinoid, aboral view showing absence of spines at the aboral pole. Credit: Paul Morris/Wikipedia (CC BY-SA 2.0)