Riemann, F. (1975). Einwanderung mariner Nematoden in das Süsswasser. Untersuchungen in Kolumbien im vergleich mit aussertropischen Regionen. Int. Revue ges. Hydrobiol. 60 (3): 393-407.
The available information on the distribution of nematodes does not demonstrate a significant latitudinal difference in the numbers of marine species colonizing freshwaters. This result contrasts with the often-stated comparative richness of marine elements in tropical freshwaters, as established by macrofauna observations. Because of this discrepancy the arguments explaining the abundance of marine elements in tropical freshwaters are reconsidered in physiological, statistical and historical perspective.