''Sclerodactyla briareus'', commonly known as the hairy sea cucumber, is a
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of marine
invertebrate
Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...
in the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Sclerodactylidae
Sclerodactylidae is a family of sea cucumbers, marine invertebrates with elongated bodies, leathery skins and tentacles.
Members of the family are characterised by the complex ring of ossicles
The ossicles (also called auditory ossicles) are ...
. It is found in shallow waters in the western Atlantic Ocean.
Description
''Sclerodactyla briareus'' is an elongated oval or cigar-shaped
sea cucumber
Sea cucumbers are echinoderms from the class (biology), class Holothuroidea ( ). They are benthic marine animals found on the sea floor worldwide, and the number of known holothuroid species worldwide is about 1,786, with the greatest number be ...
and grows to about . It often adopts a characteristic pose with both ends raised above the substrate. At the anterior end there is a mouth surrounded by a ring of ten, short, branched feeding
tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...
s. These are modified
tube feet
Tube or tubes may refer to:
* Tube (2003 film), ''Tube'' (2003 film), a 2003 Korean film
* "Tubes" (Peter Dale), performer on the Soccer AM#Tubes, Soccer AM television show
* Tube (band), a Japanese rock band
* Tube & Berger, the alias of dance/e ...
that can be retracted back into the mouth when the animal is not feeding. The surface of the body is divided into five
ambulacral
Ambulacral is a term typically used in the context of anatomical parts of the phylum Echinodermata or class Asteroidea and Edrioasteroidea. Echinoderms can have ambulacral parts that include ossicles, plates, spines, and suckers. For example, sea ...
areas with five shallow interambulacral grooves in between. Internally there are five bands of muscle running along the ambulacrae and there are also transverse bands of muscles. Just behind the tentacles is a group of small ossicles, calcareous stiffening plates, forming a short tube surrounding the pharynx. These provide a skeletal support for the muscles and internal organs. The skin is thick and leathery and the tube feet are scattered rather than being in orderly rows, protruding as soft finger-like projections from the body wall.
[''Sclerodactyla briareus'']
Invertebrate Anatomy OnLine. Retrieved 2012-02-12. The minute calcareous spicules that are embedded in the skin are characteristic for the species, being square or round and table-shaped with spires formed of four pillars. The color is dark greenish-brown or charcoal grey with pale grey tentacles on blackish stems.
[''Sclerodactyla briareus'']
Encyclopedia of Life. Retrieved 2012-02-12.
Distribution
''Sclerodactyla briareus'' is found in shallow water along the east coast of the United States from
Massachusetts
Massachusetts ( ; ), officially the Commonwealth of Massachusetts, is a U.S. state, state in the New England region of the Northeastern United States. It borders the Atlantic Ocean and the Gulf of Maine to its east, Connecticut and Rhode ...
to
Florida
Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...
, plus the
Gulf of Mexico
The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...
, the
Caribbean Sea
The Caribbean Sea is a sea of the Atlantic Ocean, North Atlantic Ocean in the tropics of the Western Hemisphere, located south of the Gulf of Mexico and southwest of the Sargasso Sea. It is bounded by the Greater Antilles to the north from Cuba ...
, and extending southward as far as
Venezuela
Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...
.
[
]
Biology
''Sclerodactyla briareus'' is a scavenger
Scavengers are animals that consume Corpse decomposition, dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a he ...
and filter feeder
Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a s ...
, collecting organic matter with its feeding tentacles and thrusting the particles into its mouth. It is gonochoristic with individuals being either male or female although there is no outward difference in appearance. Fertilization is external and the developing larvae form part of the plankton
Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...
.[
''Sclerodactyla briareus'' burrows in soft substrates and is more tolerant than many other ]echinoderm
An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as ...
s of water with low salinity
Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...
levels or low oxygen levels. If threatened by predators it can eject its viscera
In a multicellular organism, an organ is a collection of tissues joined in a structural unit to serve a common function. In the hierarchy of life, an organ lies between tissue and an organ system. Tissues are formed from same type cells to a ...
in a sticky white mass to confuse and deter the aggressor.[
]
References