Starfish Starfish Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or "basket stars". About 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters. They are found from the intertidal zone down to abyssal depths, below the surface. Starfish are marine invertebrates. They typically have a central disc and five arms, though some species have a larger number of arms. The aboral or upper surface may be smooth,
Ferreira's spiny tree-rat Ferreira's spiny tree-rat Ferreira's spiny tree-rat, "Mesomys hispidus", is a spiny rat species from South America. It is found in Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname and Venezuela. The etymology of the species name corresponds to the Latin word "" meaning "bristly". The description of "Mesomys hispidus" was conducted on a specimen collected by the naturalist Alexandre Rodrigues Ferreira during his travels in Amazonian Brazil, hence the species name. Initially deposited in the Museu Real d'Ajuda of Portugal, it has been brought to Paris in 1808 after the plundering of Lisbon by the armies of Napoleon. Then,