Morphology, Biometry and Ecology of Arcella excavata Cunningham, 1919 (Rhizopoda: Arcellinida)

Milcho Todorov ； Vassil Golemansky

《Acta Protozoologica》 42卷2期 (2003/06) Pp. 105-111

並列摘要

Testate amoeba Arcella excavata Cunningham, 1919, isolated from the aeration tanks of the Sofia's Wastewater Treatment Plant and its morphology, biometry and ecology have been investigated. Based on the rich live material (120 specimens), a detailed morphological description of A. excavata and new data about the cytoplasm and the nuclei of the species are supplied. It was found out that A. excavata is a multinuclear species and the nuclei are usually 3 or 4, rarely 5-6 (1-2% only). These new data, as well as the characteristic shape of the shell and its bigger depth, show clearly that A. excavata is a separate, well distinguishing species. The size frequency distribution analysis indicates that A. excavata is a size-monomorphic species, characterized by a main-size class and a small-size range (all measured individuals have a shell length of 60-70 μm and 98% have a shell breadth of 55-66 μm). The present study shows that A. excavata inhabits polluted waters also and this fact does not confirm the conclusion of Snegovaya that it can be used as a bioindicator of the waters with the saprobity β-α. Probably, it is also a freshwater eurybiont as well as the majority of the known species of family Arcellidae.

並列關鍵字

Arcella excavata ； biometry ； ecology ； morphology ； Rhizopoda ； Testacea