Altitudinal distribution of tropical planktonic Cladocera

Abstract

The altitudinal distributions of planktonic Cladocera in Africa in three latitudinal bands: 0-10 ", 10-20 " and 28-31 " are described. Some species have altitudinal ranges of 2000 m within a latitudinal band of 10 ". It is possible to distinguish tropical species which do not extend up to high altitudes, particularly at higher latitudes. At the lowest latitudes, some species are found only at high altitudes, but occur at progressively lower altitudes with increasing latitude: Daphnia pulex and D. obtusa are good examples. A study in South America, with a smaller database, gives similar results.

Invasion of an asexual American water flea clone throughout Africa and rapid displacement of a native sibling species

“…Considering that all modern Kenyan D. pulex populations sampled thus far solely consist of this invading clone (Mergeay et al 2005), we sampled D. pulex populations throughout Africa to establish its wider distribution. Historical and new ecological data (Sars 1916;Brehm-Eger 1912;Lowndes 1936;Brehm 1960;Green 1990Green , 1995Hart 1992;Samraoui et al 1998;Mergeay et al 2006) suggest that this species is generally absent from the warm tropical lowlands and subtropical desert regions, being mainly restricted to standing waters in the cooler regions of coastal North and South Africa, and the mountainous regions of East Africa (figure 3b). In our collection of 177 modern zooplankton samples from a wide range of aquatic habitat types, we found D. pulex in 15 locations (see electronic supplementary material, table 1) geographically distributed in accordance with this known African distribution range (figure 3b).…”