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SYNOPTIC DESCRIPTION OF THE PHYLUM HETEROLOBOSA

SYNOPTIC DESCRIPTION OF THE PHYLUM HETEROLOBOSA (PAGE AND BLANTON 1985)

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HETEROLOBOSA LINKS

Introduction

Hierarchical Classification

The following description of the Phylum Heterolobosa was taken from Patterson (1999), Margulis and Schwartz (1998), and Dyer (1990), and Cavalier-Smith (2003a).

I. SYNONYMS: Amoeboflagellates, Schizopyrenida, Heterolobosea.

II. NUMBER: Poorly studied, but less than 100 species and 16 genera.

III. PHYLUM CHARACTERISTICS:

  • A. Structure and Physiology
    • Cell Form: Unicellular.
    • Flagella: One to two to four flagella, flagella can be withdrawn very quickly; directed anteriorly (text with tooltip) An anteriorly-directed flagellum extends in the direction of the motion of the motile cell. The interpretation is that the flagellum functions by pulling the cell. .
    • Basal Bodies: Parallel (text with tooltip) Basal bodies are parallel when their orientation relative to each other is parallel. and associated with the nucleus. Contain a rhizoplast (text with tooltip) A rhizoplast is a striated root system that extends from the basal body tinto the cell, usually to the nuclear envelope. , a striated flagellar root (text with tooltip) Striated roots (also called kinetodesma, banded roots, kinetodesmal fibers, or striated fibers) are banded flagellar roots that elaborate from basal bodies. They form a distinctive and diagnostic network in the Ciliata. that connects the basal bodies to the nucleus.
    • Cell Covering: Many are amoeboid, producing eruptive pseudopodia (text with tooltip) tipso ; no specialized covering.
    • Chloroplasts (text with tooltip) Chromoplast is the general term for a photosynthetic organelle. Technically, a chloroplast is a particular chromoplast in which the dominant chlorophylls are A and B. : No chloroplasts.
    • Food Reserves: Not reported.
    • Mitochondria: Their cristae are swollen and saccate, interpreted as discoid (text with tooltip) Discoid cristae (crista, sing.) are swollen tube-like cristae within certain mitochondria. . Platycristate (text with tooltip) Flat cristae (crista, sing.) are wall-like cristae within certain mitochondria. mitochondria in Fonticula, a genus that otherwise has characters of this phylum. Percolomonads have mitochondria, but they lack 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: Large with distinctive endosome.
    • Centrioles: Not reported.
    • Inclusions and Ejectile Organelles:
    • Food vacuoles.
  • B. MITOSIS, MEIOSIS AND LIFE HISTORY
    • Mitosis: Closed mitosis (text with tooltip) Mitosis is closed when the segregation of daughter chromosomes occurs within the bounds of the nuclear membrane (the nuclear membrane does not break down). with internal spindle (text with tooltip) An intranuclear spindle elaborates within the nuclear membrane of an organism with closed mitosis. ; Promitotic (text with tooltip) Promitotic (adj.) mitosis occurs in closed mitotic systems with an intrnuclear spindle and a persistent nucleolus. .
    • Meiosis: Not reported.
    • Sexual Reproduction and Life History: Not reported.
  • C. Ecology: Freshwater to marine; free-living, saprobic, phagotrophic and parasitic.
LITERATURE CITED

Brugerolle, G., and A. G. B. Simpson. 2004. The flagellar apparatus of heteroloboseans. Journal of Eukaryotic Microbiology. 51(1): 96-107.

Cavalier-Smith, T. 2003a. Protist phylogeny and the high-level classification of Protozoa. European Journal of Protistology. 39:338-348.

Dyer, B.D. 1990a. Amoebomastigota. 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. 186-190.

Grell, K. G. 1973. Protozoology. Springer-Verlag. New York.

Kudo, R.R. 1966. Protozoology. 5th ed. Charles C. Thomas Publisher. Springfield.

Lee, J. J., S. H. Hunter, and E. C. Bovee, eds. 1985. An Illustrated Guide to the Protozoa. Society of Protozoologists. Lawrence, Kansas.

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.

Nikolaev, S.I., C. Berney, J. Fahrni, I. Bolivar, S. Polet, A.P. Mylnikov, V.V. Aleshin, N.B. Petrov, and J. Pawlowski. 2004. The twilight of Heliozoa and rise of Rhizaria, an emerging supergroup of amoeboid eukaryotes. Proceedings of the National Academy of Sciences. USA. 101(21): 8066-8071.

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.
By Jack R. Holt. Last revised: 02/15/2012
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