Neopetrosia proxima


Neopetrosia proxima is a species of marine petrosiid sponge native to the tropical and subtropical waters of the western Atlantic Ocean.

Taxonomy

Neopetrosia proxima was originally described by the French naturalist Édouard Placide Duchassaing de Fontbressin and the Italian naturalist in 1864 as Thalysias proxima. It was transferred from the genus Xestospongia to Neopetrosia in 2005. It is classified under the family Petrosiidae in the order Haplosclerida.

Description

Neopetrosia proxima is externally brown, purplish brown, or maroon in coloration, while internally it is light tan. They form thick spreading masses on the substrate. The masses are highly variable in shape, with a somewhat wrinkled surface. The surface is generally smooth in appearance, though it has the texture of fine sandpaper when touched. The consistency is hard but not brittle. It is very difficult to cut or tear and crumbles when crushed. Injured surfaces are distinctively sticky to the touch.
The sponge mass is lobated, with regular to irregularly shaped lobes typically tall. Each lobe has one opening about in diameter, either located flush on the surface or elevated in small chimneys. The spicules are composed solely of strongyles, cylindrical in shape with rounded ends.

Ecology

N. proxima serves as a host to symbiotic cyanobacteria, as well as colonies of the eusocial snapping shrimp in the genus Synalpheus.
The larvae are positively phototrophic.

Distribution

This species is found in the tropical and subtropical waters of the western Atlantic Ocean, from the Gulf of Mexico off the coast of the United States to the Caribbean Sea. They are also found off the coasts of Brazil and Venezuela.