The areas or range where a species is found.

Different types of distribution taht are distinguished are:
- range: the area of actual breeding;
- sediment range: where it is found in the sediment;
- distribution area
- the total horizontal coverage;
- expatriation range;
- the area with breeding specimens where, however, the population can not support itself;
- sterile expatriation range: where specimens are found that can not reproduce.