''Tripos muelleri'' is a species of

dinoflagellate The Dinoflagellates (), also called Dinophytes, are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered protists. Dinoflagellates are mostly marine plankton, but they are also commo ...

s of the genus ''

Tripos TRIPOS (''TRIvial Portable Operating System'') is a computer operating system. Development started in 1976 at the Computer Laboratory of Cambridge University and it was headed by Dr. Martin Richards. The first version appeared in January 1978 a ...

''.

Anatomy

This

chromist Chromista is a proposed but polyphyletic obsolete biological kingdom, refined from the Chromalveolata, consisting of single-celled and multicellular eukaryotic species that share similar features in their photosynthetic organelles (plastids). It ...

is easy to recognize and identify among all the

phytoplankton Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater Aquatic ecosystem, ecosystems. The name comes from the Greek language, Greek words (), meaning 'plant', and (), mea ...

, because of its three horns in a

pitchfork A pitchfork or hay fork is an agricultural tool used to pitch loose material, such as hay, straw, manure, or leaves. It has a long handle and usually two to five thin tines designed to efficiently move such materials. The term is also applie ...

arrangement. The horn in the middle is called the apical horn, and it is used as a

flagellum A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many pr ...

. The other two horns are called lateral horns, and they are solely used as an aid for flotation.

Habitat

This

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), ...

lives along all the

on the

ocean The ocean is the body of salt water that covers approximately 70.8% of Earth. The ocean is conventionally divided into large bodies of water, which are also referred to as ''oceans'' (the Pacific, Atlantic, Indian Ocean, Indian, Southern Ocean ...

surface worldwide, where it is one of the dominant species. Despite this, it is usually solitary, although during reproduction season, several individuals may congregate, all of their apical horns join. This occurs when a cell

divides In mathematics, a divisor of an integer n, also called a factor of n, is an integer m that may be multiplied by some integer to produce n. In this case, one also says that n is a '' multiple'' of m. An integer n is divisible or evenly divisibl ...

, so that the

daughter cell Cell division is the process by which a parent cell divides into two daughter cells. Cell division usually occurs as part of a larger cell cycle in which the cell grows and replicates its chromosome(s) before dividing. In eukaryotes, there ar ...

s remain together, linked in short

chains A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compression but linear, rigid, and load-bearing in tension. A ...

. This particular

may sometimes be parasitized by other

s or

protists A protist ( ) or protoctist is any Eukaryote, eukaryotic organism that is not an animal, Embryophyte, land plant, or fungus. Protists do not form a Clade, natural group, or clade, but are a Paraphyly, paraphyletic grouping of all descendants o ...

History

''Tripos'' species were originally classified under the genus ''

Ceratium The genus ''Ceratium'' is restricted to a small number (about 7) of freshwater dinoflagellate species. Previously the genus contained also a large number of marine dinoflagellate species. However, these marine species have now been assigned to a ...

'', however they were reclassified to the new genus ''Neoceratium'' in 2009 following a ribosomal RNA sequencing study. However, since the name ''Neoceratium'' was preceded by an older name ''Tripos'', all names were transferred to ''Tripos''.

References

Gonyaulacales Dinoflagellate species Protists described in 1826 {{dinoflagellate-stub