Haliclona sp. A

Initially, the sponge juvenile has an irregular shape and appears white, silky and filamentous.  Over time, the sponge grows, becoming rounder and more bulbous.  The spicules become pronounced and are easily seen protruding out along the edges of the sponge.  Oscula (large excurrent pores that protrude from the sponge body) can be seen a few days after settling.

Anatomy of Haliclona

Spicules- hard, mineral spines which give form and structure to the sponge
Osculum- a large, tubular hole from which water exits the sponge body

Mature Morphology of Haliclona