Clytia hemisphaerica, commonly known as Hydroids, is a small, colonial hydroid found in marine environments worldwide. These fascinating organisms exhibit a unique life cycle, alternating between a polyp stage, attached to a substrate, and a medusa stage, free-swimming in the water column.
Description & Characteristics
Clytia hemisphaerica colonies are typically small, measuring up to a few centimeters in diameter. They consist of numerous individual polyps, each with a specialized function. The polyps are connected by a network of tubes known as the coenosarc, which allows for the transport of nutrients and other substances throughout the colony.
Habitat and Occurrence
Hydroids are commonly found in coastal waters, particularly in estuaries and harbors. They are typically found attached to various substrates, including rocks, seaweed, and docks. Clytia hemisphaerica is often abundant in the intertidal zone, where it can tolerate fluctuations in salinity and temperature. The species is also frequently found in the neritic zone, which extends from the shoreline to the edge of the continental shelf, often thriving in depths of up to 50 meters.
Taxonomy
Clytia hemisphaerica is classified within the Order Leptothecata, a group of hydroids characterized by their thin, transparent tentacles. They are further categorized within the Family Campanulariidae, known for their bell-shaped medusae. The genus Clytia encompasses several species of hydroids, each exhibiting specific characteristics and distributions.
Feeding
Hydroids are carnivorous, feeding primarily on plankton. The polyps use their tentacles, armed with stinging cells called nematocysts, to capture small organisms like copepods, larvae, and other microscopic creatures. The captured prey is then transported to the mouth of the polyp and digested.
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