Amastigomonas mutabilis (Griessmann 1913) Molina and Nerad 1991

Introduction

This species of Amastigomonas is distinguished by its large size and by having granules lying adjacent to the trailing flagellum on its ventral side.

Characteristics

The species is usually elliptical in shape and has been reported to be from 7 to 16 µm long. It is, like other members of the genus, dorso-ventrally flattened and flexible. There is a flexible sleeve around the base of the anterior flagellum. This flagellum is about 0.5 times the length of the cell, and it is the same thickness as the posterior flagellum. The recurrent posterior flagellum is slightly longer than the cell and trails under the body, to which it attaches loosely in a slight groove. The nucleus is situated subapically near the right margin of the cell. Some cells have granules alongside the recurrent flagellum.

Distribution

This species has been recorded from marine sites in subtropical Australia, Brazil, Denmark, England, France, Greenland and North Atlantic (Lee and Patterson, 2000).

Discussion

This species was first described as Rhynchomonas mutabilis (Griessmann 1913). It was then transferred to Thecamonas by Larsen and Patterson (1990) and to Amastigomonas by Molina and Nerad (1991). The species is distinguished because it is bigger than the more common A. debruynei, because it has a longer anterior flagellum and because it may have ventral granules. However, as noted under A. debruynei, the distinctions may not be sustainable as A. debruynei overlaps with A. bermudensis in size (A. bermudensis is 8-11.5 µm long) , and A. bermudensis overlaps with A. mutabilis. Also, A. mutabilis overlaps with A. terricola in the appareance of the anterior flagllum.

Other Names for Amastigomonas mutabilis (Griessmann 1913) Molina and Nerad 1991

• Rhynchomonas mutabilis Griessmann 1913
• Thecomonas mutabilis Larsen and Patterson 1990

References

Griessmann, K. 1913. Über marine Flagellaten. Archiv für Protistenkunde 32 (year 1914): 1-78.

Larsen, J. and Patterson, D. J. 1990. Some flagellates (Protista) from tropical marine sediments. Journal of Natural History 24: 801-937.

Lee, W. J. and Patterson, D. J. 2000. Heterotrophic flagellates (Protista) from marine sediments of Botany Bay, Australia. Journal of Natural History 34: 483-562.

Molina, F. I. and Nerad, T. A. 1991. Ultrastructure of Amastigomonas bermudensis ATCC 50234 sp.nov. - a new heterotrophic marine flagellate. European Journal of Protistology 27: 386-396.