Bicosoecida ( ICZN) or Bicosoecales/Bicoecea ( ICBN) is an order of Bikosea, a small group of unicellular

flagellate A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and the ...

s, included among the

stramenopile The stramenopiles, also called heterokonts, are protists distinguished by the presence of stiff tripartite external hairs. In most species, the hairs are attached to flagella, in some they are attached to other areas of the cellular surface, an ...

s. Informally known as bicosoecids, they are free-living cells, with no

chloroplast A chloroplast () is a type of membrane-bound organelle, organelle known as a plastid that conducts photosynthesis mostly in plant cell, plant and algae, algal cells. Chloroplasts have a high concentration of chlorophyll pigments which captur ...

s, and in some genera are encased in a lorica. The name of the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

'' Bicosoeca'' described by James-Clark in 1866 is derived from Greek roots (, vase, bowl, plus ''oekein'', inhabit). The philologically preferable compound would be ''Bicoeca'', as "corrected" by Stein in 1878 and followed by most subsequent authors. However, according to the ICBN and ICZN, the original spelling of the name cannot be considered incorrect and it must be used in its original form. The group was formerly considered to be related to the Chrysophyceae. Some authors use the vernacular term "bicosoecid" (or "bicoecid") in a narrower sense, only for ''Bicosoeca'', applying "bicoeceans" to ''Bicosoeca'' and related groups like '' Cafeteria''. With the advent of using molecular phylogenies to resolve relationships of many

eukaryote The eukaryotes ( ) constitute the Domain (biology), domain of Eukaryota or Eukarya, organisms whose Cell (biology), cells have a membrane-bound cell nucleus, nucleus. All animals, plants, Fungus, fungi, seaweeds, and many unicellular organisms ...

s the original circumscription of bicosoecids has been greatly expanded upon to include other orders and the rank has changed from an order to a class.

Morphology

Classification

* Family Labromonadidae

Cavalier-Smith Thomas (Tom) Cavalier-Smith, Royal Society, FRS, Royal Society of Canada, FRSC, Natural Environment Research Council, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Departme ...

2006 ** '' Labromonas'' Cavalier-Smith 2006 * Family Bicosoecaceae Ritter von Stein 1878 ** '' Poteriodendron'' Stein 1878 ** '' Bicosoeca'' Clark 1866 ** '' Hedraeophysa'' Kent 1880 * Family Cafeteriaceae Moestrup 1995 ** '' Cafeteria'' Fenchel & Patterson 1988 ** '' Symbiomonas'' Guillou & Chrétiennot-Dinet 1999

References

Bibliography

* Hibberd, D. J. (1986). Ultrastructure of the Chrysophyceae. Colorless forms
p. 29-30
In: ''Chrysophytes: Aspects and Problems''. Kristiansen, J. and R.A. Andersen ds. Cambridge University Press, Cambridge.

External links

* Stramenopile orders {{Heterokont-stub