|Associations of planktonic and periphytic rotifers in a tropical swamp, the Okavango Delta, Southern Africa|
Green, J. (2003). Associations of planktonic and periphytic rotifers in a tropical swamp, the Okavango Delta, Southern Africa. Hydrobiologia 490: 197-209
In: Hydrobiologia. Springer: The Hague. ISSN 0018-8158, more
The Okavango Delta has an annual flood cycle that spreads slowly from the northwestern ‘panhandle’ into a widening delta to the southeast. Rotifers were sampled from areas where the flood was active, and from other areas not yet reached by the flood. In still waters, the samples were dominated by euplanktonic rotifers, particularly of the genera Brachionus, Keratella and Hexarthra, with about 20 species per 1000 individuals at a station. Where the water was moving the samples were dominated by periphytic rotifers, with over 100 species per 1000 individuals at a single station. The periphytic species were dominated by the genus Lecane, with over 45 species, followed by Lepadella with 24 species, and Trichocerca with 23 species. Comparison of the Okavango with six other tropical localities reveals fairly consistent ratios of the numbers of species in the periphytic genera Lecane, Lepadella andTrichocerca, indicating that there may be assembly rules for communities of tropical periphytic rotifers.