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The aquatic microfauna of Africa is poorly characterized, especially in the case of planktonic rotifers inhabiting waterbodies other than large lakes. In addition, little is known about factors that structure these communities. Here, we assessed the roles of climatic region, habitat type, macrophyte abundance, and a suite of abiotic environmental factors in determining rotifer species’ richness and composition in waterbodies located across a 2300 m altitudinal gradient in Kenya. Plankton samples were obtained from 33 sites in 23 waterbodies. From these, 93 rotifer taxa were identified from 18 families comprising 31 genera. About one fourth (25 taxa) were new records for Kenya, from which 4 species were new for Africa. Species richness was the highest in permanent as compared to temporary habitats. Richness was strongly positively correlated with all environmental factors and strongly influenced by macrophyte abundance. When spatial structure was added to the GLM model, species richness was no longer significantly correlated with macrophytes. Unconstrained detrended correspondence analysis conducted at the species level indicated four suites of species associated with either (1) longitude, (2) elevation, (3) latitude, temperature, and hydroperiod, or (4) macrophytes. This study contributes to our knowledge of the patterns of rotifer biogeography and species richness in Africa.
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A synthesis of the biogeographical distribution of Rotifera in Africa
Abstract The rotifer fauna of Africa has been studied for >100 years, but there has been no recent synthesis. We compiled data from 265 publications that reported information on African rotifers. Our dataset yielded information on the distribution of 765 taxa from ~1850 separate sites; these included both natural and artificial habitats such as lakes, ponds, puddles, oases, artificial systems, rivers and wetlands. A heat map of predicted rotifer biodiversity indicated that the greatest diversity should be present in the sub-Saharan region including a large hotspot in Mali and several smaller ones scattered in that region. Lakes Kariba, Tanganyika and Malawi showed high-predicted diversity, but surprisingly, Lake Victoria had lower diversity than expected. Two regions showed unusually high-predicted diversity: northwestern Algeria extending into Morocco and Egypt. Equatorial Africa is rich in habitats well suited for rotifers, yet their predicted biodiversity seems low. Latitude and elevation were negatively correlated with richness, while permanent water source and littoral zone were positively correlated according to generalized linear modeling results. Partial RDA analyses showed significant correlations among several environmental features and species occurrences. It is clear that more survey work remains to be done to achieve a better understanding of African rotifers.
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- Award ID(s):
- 2051704
- PAR ID:
- 10387815
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Plankton Research
- Volume:
- 45
- Issue:
- 1
- ISSN:
- 0142-7873
- Format(s):
- Medium: X Size: p. 65-81
- Size(s):
- p. 65-81
- Sponsoring Org:
- National Science Foundation
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