Clathrina coriacea is a species of marine sponge belonging to the phylum Porifera, class Calcarea, and family Clathrinidae. It is commonly referred to as a calcareous sponge due to its skeletal structure composed of calcium carbonate spicules.
Taxonomy
- Phylum: Porifera (Sponges)
- Class: Calcarea (Calcareous sponges)
- Order: Clathrinida
- Family: Clathrinidae
- Genus: Clathrina
- Species: Clathrina coriacea (Montagu, 1818)
Description
Clathrina coriacea typically forms small, encrusting colonies that can be cushion-shaped or composed of an intricate network of interconnected, thin tubes, a characteristic feature of the genus Clathrina often referred to as a clathroid structure. The color of the sponge is variable but commonly ranges from white, cream, or pale yellow to sometimes a dull orange or brown. Its texture can be somewhat firm or leathery, which may have inspired its specific epithet "coriacea" (meaning leathery). Like other calcareous sponges, its skeleton is made up of calcareous spicules, predominantly triactines (three-pointed) and tetractines (four-pointed), which are robust and contribute to its structural integrity. The oscula (excurrent openings) are small and scattered across the surface.
Habitat and Distribution
This species is a marine organism, typically found in shallow to moderate subtidal depths, though it can occasionally occur in sheltered intertidal zones. It prefers to attach to hard substrates such as rocks, shells, coral rubble, and other stable surfaces. Clathrina coriacea is widely distributed in the North Atlantic Ocean, including the coasts of Europe (such as the British Isles, France, and the Mediterranean Sea), and may extend into other temperate regions.
Biology and Ecology
As a sponge, Clathrina coriacea is a sessile filter feeder. It draws water through numerous small pores (ostia) into its internal canal system, where specialized cells called choanocytes capture microscopic organic particles, bacteria, and plankton. The filtered water is then expelled through the oscula. Sponges like C. coriacea play an important ecological role in benthic ecosystems by filtering large volumes of water, contributing to water clarity, and recycling nutrients. They reproduce both asexually (through budding or fragmentation) and sexually, releasing larvae that can disperse to new locations before settling and developing into adult sponges.