A group of organisms that differ from all other groups of organisms and that
are capable of breeding and producing fertile offspring. This is the smallest
unit of classification for plants and animals.
Glossary of Common Terms and Definitions in Marine
An interbreeding group of organisms that is reproductively isolated from all
other organisms, although there are many partial exceptions to this rule in
particular taxa. Operationally, the term species is a generally agreed
fundamental taxonomic unit, based on morphological or genetic similarity, that
once described and accepted is associated with a unique scientific name.
Millennium Ecosystem Assessment
Alien species - Endangered species
To read about this term in context:
GreenFacts Summary on Biodiversity & Human Well-being:
Deutsch: Art (Biologie)