Black Sea Cucumber: Holothuria atra
In a Sea Cucumber, the pharynx is located behind the mouth and is surrounded by a ring of ten calcareous plates. In most sea cucumbers, this is the only major part of the skeleton. It creates 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 of sea cucumber possess an oesophagus and stomach. However, 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 as the anus. A Sea Cucumber's diet consists of plankton, and other decomposing matter. Sea Cucumbers wait in currents, and catch there prey flowing in these current using their tentacles.