''Sclerodactyla briareus'', commonly known as the hairy sea cucumber, is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of marine
invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Sclerodactylidae
Sclerodactylidae is a family of sea cucumbers
Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on t ...
. 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 Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothuria ...
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 feet (technically podia) are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on britt ...
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 Sea star, Asteroidea and Edrioasteroidea. Echinoderms can have ambulacral parts that include Ossicle (echinoderm), ossicles, plates, spines ...
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
to
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
, plus the
Gulf of Mexico
The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...
, the
Caribbean Sea
The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Zee; pap, Laman Karibe) is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico ...
, and extending southward as far as
Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
.
[
]
Biology
''Sclerodactyla briareus'' is a scavenger
Scavengers are animals that consume 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 herbivorous feeding b ...
and filter feeder
Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...
, collecting organic matter with its feeding tentacles and thrusting the particles into its mouth. It is gonochoristic
In biology, gonochorism is a sexual system where there are only two sexes and each individual organism is either male or female. The term gonochorism is usually applied in animal species, the vast majority of which are gonochoric.
Gonochorism c ...
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 found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...
.[
''Sclerodactyla briareus'' burrows in soft substrates and is more tolerant than many other ]echinoderm
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea ...
s of water with low salinity
Salinity () is the saltiness or amount of 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 dimensionless and equal ...
levels or low oxygen levels. If threatened by predators it can eject its viscera
In biology, 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 act together in a ...
in a sticky white mass to confuse and deter the aggressor.[
]
References