Bicosoecida

Bicosoecida (ICZN) or Bicosoecales/Bicoecea (ICBN) is an order of Bikosea, a small group of unicellular flagellates, included among the stramenopiles. Informally known as bicosoecids, they are free-living cells, with no chloroplasts, and in some genera are encased in a lorica.

Bicosoecida
Cafeteria roenbergensis, a non-loricate bicosoecid
Scientific classification
Domain:	Eukaryota
(unranked):	SAR
Superphylum:	Stramenopiles
Class:	Bikosea
Subclass:	Bicosidia
Superorder:	Cyathobodoniae
Order:	Bicosoecida Grassé, 1926[1] emend. Karpov, 1998[2] Honigberg et al., 1964, Zhukov, 1978, Karpov, 1998, 2000
Families
Rictidia Bicosidia
Synonyms
Bikoecida Stein, 1878 Bicoecinae Grassé, 1926[3] Bicoecidea Grassé & Deflandre in Grassé, 1952[4] Bicosoecales Bourrelly, 1968, 1981 Bicoecales Kristiansen, 1972[5] Bicosoecophyceae Casper, 1974, Loeblich III & Loeblich 1979[6] Bicosoecea Cavalier-Smith, 1986 Bicoecia Cavalier-Smith, 1989 Bicoecea Cavalier-Smith, 1993 Bicocoecida van den Hoek et al., 1995 Bicosoecida Honigberg et al., 1964, Zhukov, 1978, Karpov, 1998, 2000

The name of the type genus Bicosoeca described by James-Clark in 1866 is derived from Greek roots (bikos, 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.^[7]

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.^[8]

With the advent of using molecular phylogenies to resolve relationships of many eukaryotes 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.^[9]

Morphology

Representation of a bicosoecid

1. Anterior flagellum
2. Mastigoneme
3. "Lip"
4. Flagellar root subtending lip
5. Bacterial prey
6. Golgi apparatus, packages proteins
7. Phagocytic vesicle
8. Nucleus
9. Nucleolus
10. Endoplasmic reticulum, the transport network for molecules going to specific parts of the cell
11. Mitochondrion; creates ATP (energy) for the cell
12. Contractile vacuole, regulates the quantity of water inside a cell
13. Digestive Vacuole
14. Recurrent flagellum
15. Lorica

Classification

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

References

1. Grassé, P.-P. Contribution à l'étude des flagellés parasites. Archives de zoologie expérimentale et générale, t. 65, 1926, pages 345-602
2. Ultrastructure and 18S rRNA gene sequence of a small heterotrophic flagellate Siluania monomastiga gen. et sp. nov. (Bicosoecida). S. A. Karpov, R. Kersanach, D. M. Williams - European Journal of Protistology, 1998
3. Grassé, P.-P. Contribution à l'étude des flagellés parasites. Archives de zoologie expérimentale et générale, t. 65, 1926, pp. 345–602 [576], disponible at Gallica.
4. Grassé, P.-P. & Deflandre, G . (1952). Ordre des Bicoecidea. In: Grassé, P.-P. (Ed.). Traité de Zoologie. Vol. 1, fasc. 1. Phylogénie. Protozoaries: Generalités, Flagellés. Masson et Cie, Paris. 599-601.
5. Kristiansen, Jørgen (1972). "Structure and occurrence of Bicoeca crystallina, with remarks on the taxonomic position of the Bicoecales". British Phycological Journal. 7 (1): 1–12. doi:10.1080/00071617200650011.
6. Loeblich III, Alfred R. & Loeblich, Laurel Ann. 1979. Division Chrysophyta, pp. 411–423. In: CRC Handbook of Microbiology, 2nd ed., vol. 2, Fungi, Algae, Protozoa, and Viruses, ed. by A. I.Laskin and H. A. Lechevalier, CRC Press, Inc., West Palm Beach, FL.
7. Hibberd, David J. (1978). "Bicosoeca accreta sp. nov., a flagellate accumulating extraneous silica fragments". British Phycological Journal. 13 (2): 161–166. doi:10.1080/00071617800650201.
8. Cavalier-Smith, T; Chao, E. E. (2006). "Phylogeny and megasystematics of phagotrophic heterokonts (kingdom Chromista)". Journal of Molecular Evolution. 62 (4): 388–420. Bibcode:2006JMolE..62..388C. doi:10.1007/s00239-004-0353-8. PMID 16557340. S2CID 29567514. Supplementary material .
9. Cavalier-Smith, T; Scoble, J. M. (2013). "Phylogeny of Heterokonta: Incisomonas marina, a uniciliate gliding opalozoan related to Solenicola (Nanomonadea), and evidence that Actinophryida evolved from raphidophytes". European Journal of Protistology. 49 (3): 328–353. doi:10.1016/j.ejop.2012.09.002. PMID 23219323.

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 [Eds.]. Cambridge University Press, Cambridge.

External links

• Data related to Bicosoecida at Wikispecies