SYNOPTIC DESCRIPTION OF THE PHYLUM BICOSOECIDA
| EUKARYA> CHROMALVEOLATA> HETEROKONTAE> BICOSOECIDA |
BICOSOECIDA LINKS
| The following description comes from Margulis and Schwartz (1988 and 1998), Kudo (1966), Grell (1976), and Dyer (1990). |
I. SYNONYMS: Bicosoecids, bicoecids.
II. NUMBER: >40 species.
III. PHYLUM CHARACTERISTICS:
- A. Structure and Physiology
- Cell Form: Unicellular.
- Flagella: Two flagella which originate from an anterior depression; a tinsel flagellum (text with tooltip) A tinsel flagellum is one that is covered with flagellar hairs and thus appears thicker in light microscopy. Usually, tinsel flagella are anteriorally-directed. directed to outside; recurrent whiplash flagellum (text with tooltip) (1) A whiplash flagellum is a eukaryotic 9+2 flagellum with few or no flagellar hairs or scales. These may be directed anteriorly or posteriorly. (2) A whiplash flagellum is free of hair-like mastigonemes and usually is trailing or posteriorly-directed. stays within lorica and is attached to lorica.
- Basal Bodies: Basal bodies orthogonal ( perpendicular (text with tooltip) Basal bodies are perpendicular (or orthogonal) when their orientation relative to each other is at a right angle. ) with microtubular array which runs from basal bodies around cytostome.
- Cell Covering: Naked with a cytosome (text with tooltip) Cytostome (literally cell mouth) is a permanent opening into the cell into which food particles move and are incorporated into food vacuoles. and a groove in which recurrent flagellum (text with tooltip) Recurrent flagella bend to the posterior end of the cell. Typically, they are identified as recurrent when anteriorly-directed flagella are present. lies; cell lies within secreted lorica (text with tooltip) A lorica is a covering that occurs outside of the cell membrane. It is secreted by the cell and usually is organic. Loricas do not completely enclose the cell. Periplasts, structures similar to loricas do enclose the cell. Lorica stands for armour. .
- Chloroplasts: Not present.
- Food Reserves: Not reported.
- Mitochondria: Tubular cristae (text with tooltip) Mitochondrial cristae that form as extended saccate structures or tubes are called tubular cristae. .
- Golgi (text with tooltip) Golgi apparatus (also called dictyosome) is an internal membrane system of stacked flattened sacs. They occur in nearly all eukaryotes and are involved in storing and secreting cellular products. : Present.
- Nucleus: Uninucleate. Endosome?
- Centrioles: Not reported.
- Inclusions and Ejectile Organelles: Food vacuoles; contractile vacuoles.
- B. Mitosis, Meiosis and Life History
- Mitosis: Not reported.
- Meiosis: Not reported.
- Sexual Reproduction and Life History: Not reported but free-swimming aloricate forms have been reported.
- C. Ecology: Freshwater and marine; free-living, phagotrophic.
| LITERATURE CITED Baldauf, S. L. 2003a. The deep roots of eukaryotes. Science. 300 (5626): 1701-1703. Cavalier-Smith, T. 1989. The Kingdom Chromista. In: Green, J.C., B.S.C. Leadbeater, and W.L. Diver, eds. The Chromophyte Algae: Problems and Perspectives. Systematics Association Special Volume No. 38. Clarendon Press. Oxford. pp. 381-407. Dyer, B. D. 1990b. Bicoecids. In: Margulis, L., J.O. Corliss, M. Melkonian, and D.J. Chapman, eds. 1990. Handbook of the Protoctista; the Structure, Cultivation, Habits and Life Histories of the Eukaryotic Microorganisms and Their Descendants Exclusive of Animals, Plants and Fungi. Jones and Bartlett Publishers. Boston. pp. 191-193. Grell, K. G. 1973. Protozoology. Springer-Verlag. New York. Kudo, R.R. 1966. Protozoology. 5th ed. Charles C. Thomas Publisher. Springfield. Margulis, L. and K. Schwartz. 1988. Five kingdoms, an illustrated guide to the phyla of life on earth. 2nd Edition. W.H. Freeman and Co. New York. Margulis, L. and K. Schwartz. 1998. Five kingdoms, an illustrated guide to the phyla of life on earth. 3rd Edition. W. H. Freeman and Company. New York. Patterson, D. J. 1999. The diversity of eukaryotes. American Naturalist. 154 (Suppl.): S96–S124. Sleigh, M.A., J.D. Dodge and D.J. Patterson. 1984. Kingdom Protista. In: Barnes, R.K.S., ed. A Synoptic Classification of Living Organisms. Sinauer Associates, Inc. Sunderland, Mass. Sogin, M. L. and D. J. Patterson. 1995. Stramenopiles. Version 01 January 1995 (under construction). http://tolweb.org/Stramenopiles/2380/1995.01.01 In: The Tree of Life Web Project, http://tolweb.org/ |
| By Jack R. Holt. Last revised: 02/21/2013 |
