Beaded sea cucumber - euapta lappa
Sea cucumbers are almost all detritivores. This means that they eat the tiny scrap particles that are usually abundant in the environments that they inhabit. There are two basic modes of feeding among sea cucumbers. “Direct deposit feeding” is one method which is seen in many surface dwelling and burrowing species. In this feeding method, sea cucumbers literally wipe their tentacles over the sediments to pick up tiny particles that settle there from the water above. Sea cucumbers are efficient direct deposit feeders. The fact that fecal pellets are richer in terms of energy and nutrients than the surrounding sediments that sea cucumbers eat is evidence to this fact. The other mode of feeding is the suspension feeding. Suspension feeding sea cucumbers have finely diverticulating buccal tentacles that are used to pick particles out of the water column during feeding.
A pharynx lies behind the mouth and is surrounded by a ring of ten calcareous plates. In most sea cucumbers, this is the only substantial part of the skeleton, and it forms the point of attachment for muscles that can retract the tentacles into the body for safety as for the main muscles of the body wall. Many species possess an oesophagus and stomach, but in some the pharynx opens directly into the intestine. The intestine is typically long and coiled, and loops through the body three times before terminating in a cloacal chamber, or directly at the anus.
A pharynx lies behind the mouth and is surrounded by a ring of ten calcareous plates. In most sea cucumbers, this is the only substantial part of the skeleton, and it forms the point of attachment for muscles that can retract the tentacles into the body for safety as for the main muscles of the body wall. Many species possess an oesophagus and stomach, but in some the pharynx opens directly into the intestine. The intestine is typically long and coiled, and loops through the body three times before terminating in a cloacal chamber, or directly at the anus.