abyssopelagic zone
2
abyssopelagic zone ~zonation.
Acantharia ~Actinopoda.
Acanthocephala phylum of parasitic spiny-headed worms, which superficially
resemble Nematoda. The juveniles live in Crustacea, the adults in the intestines
of vertebrates, mostly fish. Eggs develop inside the vertebrate host, where the
provisional hooks of the pharynx are formed. Larvae develop in the water;
there they are ingested by crustaceans, in which they become mature. Once
the crustacean host is eaten by a definite host, the parasites attach to the wall
of its digestive tract.
Acarina (mites or ticks) subclass of the class Arachnida (phylum Arthropoda).
Small terrestrial or aquatic animals with eight short legs, and an unclear
segmentation or division of the body. The group is very species-rich. In
marine environments they are common in salt marshes and as meiobenthos.
Acoela order of the class Turbellaria (phylum Platyhelminthes or flatworms). Small
marine worms, common in or on the sediment.
Acoelomata animal groups which lack a body cavity (coelom) clearly as a secondary loss. Examples are the phyla Platyhelminthes and Nemertina.
acoustic release device used for recovering anchored instruments. It is placed
between a submerged buoy and its anchoring and is released from the
anchor after receiving an acoustic signal. The buoy with instruments and
the release will float to the surface to be recovered, while the disposable
anchoring weight stays on the bottom. Also used for opening and closing
Rectangular Midwater Trawls (~nets).
acoustics science that studies the properties of sound. Sound propagation properties of seawater are important both for many marine animals as a means
for sensing and communication, and for navigation, underwater detection,
and research. Many developments in the field have a naval background. The
Acoustics. (After Williams 1973)
2
abyssopelagic zone ~zonation.
Acantharia ~Actinopoda.
Acanthocephala phylum of parasitic spiny-headed worms, which superficially
resemble Nematoda. The juveniles live in Crustacea, the adults in the intestines
of vertebrates, mostly fish. Eggs develop inside the vertebrate host, where the
provisional hooks of the pharynx are formed. Larvae develop in the water;
there they are ingested by crustaceans, in which they become mature. Once
the crustacean host is eaten by a definite host, the parasites attach to the wall
of its digestive tract.
Acarina (mites or ticks) subclass of the class Arachnida (phylum Arthropoda).
Small terrestrial or aquatic animals with eight short legs, and an unclear
segmentation or division of the body. The group is very species-rich. In
marine environments they are common in salt marshes and as meiobenthos.
Acoela order of the class Turbellaria (phylum Platyhelminthes or flatworms). Small
marine worms, common in or on the sediment.
Acoelomata animal groups which lack a body cavity (coelom) clearly as a secondary loss. Examples are the phyla Platyhelminthes and Nemertina.
acoustic release device used for recovering anchored instruments. It is placed
between a submerged buoy and its anchoring and is released from the
anchor after receiving an acoustic signal. The buoy with instruments and
the release will float to the surface to be recovered, while the disposable
anchoring weight stays on the bottom. Also used for opening and closing
Rectangular Midwater Trawls (~nets).
acoustics science that studies the properties of sound. Sound propagation properties of seawater are important both for many marine animals as a means
for sensing and communication, and for navigation, underwater detection,
and research. Many developments in the field have a naval background. The
Acoustics. (After Williams 1973)