Cyclosalpa bakeri
Encyclopedia
Cyclosalpa bakeri is a salp
, a marine tunicate
in the class
Thaliacea
. It is found floating in the open sea in the Indo-Pacific region.
They are cylindrical, transparent, gelatinous animals with a rather flabby test, growing to about 15cm (6ins) long. There are openings at the anterior and posterior ends of the cylinder which can be opened or closed as needed. The bodies have seven transverse bands of muscle interspersed by white, translucent patches. A stolon grows from near the endostyle (an elongated glandular structure producing mucus for trapping food particles). The stolon is a ribbon-like organ on which a batch of aggregate forms of the animal are produced by budding
. The aggregate is the second, colonial form of the salp and is also gelatinous, transparent and flabby. It takes the shape of a radial whorl of individuals up to about 20cm (4in) in diameter. It is formed of approximately 12 zooid
s linked side by side in a shape that resembles a crown.
distribution. Its range includes tropical and temperate waters and extends as far north as Alaska
.
which are caught by a mucus net. Cyclosalpa bakeri is an extremely efficient feeder. The aggregates can grow by a quarter of their size each day and individuals can eat more than half their body mass daily.
Individuals within the aggregate are sequential hermaphrodite
s. They usually start life as females but later develop into males. Eggs are produced by the females and are fertilised by sperm from another aggregate. There is no larva
l form and a single embryo
develops in each individual in the aggregate. This later becomes detached from the aggregate and becomes a solitary individual ready to undergo asexual reproduction
by budding again. The animal's rapid growth and this alternation of generations means that the population can build up rapidly when there is a plentiful food supply such as a bloom
of phytoplankton. The salps themselves are eaten by fish, turtles, birds, jellyfish
, heteropods
, siphonophores and ctenophores.
Salp
A salp or salpa is a barrel-shaped, planktonic tunicate. It moves by contracting, thus pumping water through its gelatinous body...
, a marine tunicate
Tunicate
Tunicates, also known as urochordates, are members of the subphylum Tunicata, previously known as Urochordata, a group of underwater saclike filter feeders with incurrent and excurrent siphons that is classified within the phylum Chordata. While most tunicates live on the ocean floor, others such...
in the class
Class (biology)
In biological classification, class is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order...
Thaliacea
Thaliacea
The Thaliacea comprise a class of marine animals within the subphylum Tunicata. Unlike their bottom-dwelling relatives the ascidians, thaliaceans are free-floating for their entire lifespan. The group includes both solitary and colonial species.-Anatomy:...
. It is found floating in the open sea in the Indo-Pacific region.
Description
Like other salps, Cyclosalpa bakeri has two different phases. In one of these forms, individuals live a solitary life.They are cylindrical, transparent, gelatinous animals with a rather flabby test, growing to about 15cm (6ins) long. There are openings at the anterior and posterior ends of the cylinder which can be opened or closed as needed. The bodies have seven transverse bands of muscle interspersed by white, translucent patches. A stolon grows from near the endostyle (an elongated glandular structure producing mucus for trapping food particles). The stolon is a ribbon-like organ on which a batch of aggregate forms of the animal are produced by budding
Budding
Budding is a form of asexual reproduction in which a new organism grows on another one. The new organism remains attached as it grows, separating from the parent organism only when it is mature. Since the reproduction is asexual, the newly created organism is a clone and is genetically identical...
. The aggregate is the second, colonial form of the salp and is also gelatinous, transparent and flabby. It takes the shape of a radial whorl of individuals up to about 20cm (4in) in diameter. It is formed of approximately 12 zooid
Zooid
A zooid or zoöid is a single animal that is part of a colonial animal. The zooids can either be directly connected by tissue or share a common exoskeleton...
s linked side by side in a shape that resembles a crown.
Distribution
Cyclosalpa bakeri has an Indo-PacificIndo-Pacific
The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...
distribution. Its range includes tropical and temperate waters and extends as far north as Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
.
Biology
Cyclosalpa bakeri moves by contracting its bands of muscles rhythmically at the same time opening and closing the front and rear openings appropriately. This squeezes water out from the hollow interior and the animal moves in the opposite direction, a form of jet propulsion. This water movement brings in suspended phytoplanktonPhytoplankton
Phytoplankton are the autotrophic component of the plankton community. The name comes from the Greek words φυτόν , meaning "plant", and πλαγκτός , meaning "wanderer" or "drifter". Most phytoplankton are too small to be individually seen with the unaided eye...
which are caught by a mucus net. Cyclosalpa bakeri is an extremely efficient feeder. The aggregates can grow by a quarter of their size each day and individuals can eat more than half their body mass daily.
Individuals within the aggregate are sequential hermaphrodite
Hermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
s. They usually start life as females but later develop into males. Eggs are produced by the females and are fertilised by sperm from another aggregate. There is no larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
l form and a single embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...
develops in each individual in the aggregate. This later becomes detached from the aggregate and becomes a solitary individual ready to undergo asexual reproduction
Asexual reproduction
Asexual reproduction is a mode of reproduction by which offspring arise from a single parent, and inherit the genes of that parent only, it is reproduction which does not involve meiosis, ploidy reduction, or fertilization. A more stringent definition is agamogenesis which is reproduction without...
by budding again. The animal's rapid growth and this alternation of generations means that the population can build up rapidly when there is a plentiful food supply such as a bloom
Algal bloom
An algal bloom is a rapid increase or accumulation in the population of algae in an aquatic system. Algal blooms may occur in freshwater as well as marine environments. Typically, only one or a small number of phytoplankton species are involved, and some blooms may be recognized by discoloration...
of phytoplankton. The salps themselves are eaten by fish, turtles, birds, jellyfish
Jellyfish
Jellyfish are free-swimming members of the phylum Cnidaria. Medusa is another word for jellyfish, and refers to any free-swimming jellyfish stages in the phylum Cnidaria...
, heteropods
Pterotracheoidea
The Pterotracheoidea is, according to the Taxonomy of the Gastropoda , a taxonomic superfamily of sea snails or sea slugs, marine gastropod molluscs in the clade Littorinimorpha. They are commonly called heteropods or sea elephants.- Taxonomy :This superfamily comprises four families The...
, siphonophores and ctenophores.