The Olive Green Cockle, Lagoon Cockle, scientifically known as Cerastoderma glaucum, is a species of saltwater clam, a type of bivalve mollusc. This particular cockle species is distinguished by its olive-green shell, which has earned it its common name. It’s a fascinating creature that plays a crucial role in the marine ecosystem.
Description & Characteristics
The Olive Green Cockle’s shell can grow to a maximum size of around 45 millimeters, showcasing a distinctive olive-green hue. The exterior of the shell is often marked with radial ribs and a series of concentric growth lines. Like many bivalve molluscs, Cerastoderma glaucum has two hinged shells, with the hinge located at the dorsal side. Its shell is typically smooth and oval in shape. The interior of the shell displays a white to pale yellow coloration.
Habitat and Occurrence
The Olive Green Cockle, Lagoon Cockle, Cerastoderma glaucum, is a common sight in intertidal zones and shallow coastal waters. Its presence extends from the lower intertidal zone down to depths of approximately 20 meters. It thrives in sandy, muddy, and gravelly substrates. Often, Cerastoderma glaucum can be found in estuaries, lagoons, and bays, where it benefits from the influx of nutrients and the sheltered environment. These habitats are often characterized by brackish water conditions, meaning they are a mixture of freshwater and saltwater, which this species has adapted well to.
Taxonomy
The Olive Green Cockle, Lagoon Cockle, Cerastoderma glaucum, is scientifically classified as belonging to the Class Bivalvia, which encompasses a vast diversity of bivalve molluscs. Within the Class Bivalvia, Cerastoderma glaucum is further categorized under the Order Cardiida, an order that includes heart cockles and other similar bivalve species. Finally, it is assigned to the Family Cardiidae, a family of cockles known for their characteristic heart-shaped shells.
Feeding
The Olive Green Cockle, Lagoon Cockle, Cerastoderma glaucum, is a filter feeder, consuming plankton, a diverse range of microscopic organisms, from the surrounding water. Its feeding method involves drawing water into its mantle cavity through siphons, where it filters out the plankton particles for consumption. This vital role in the food chain contributes to the overall health of the marine ecosystem.
Image References