nominate species
/ˈnɒmɪnət ˈspiːʃɪz/ /ˈnɒmɪnət ˈspiːʃiːz/ /ˈnɒmɪnət ˈspiːsɪz/noun
1 Zoology. A species with which a particular available name is associated; a nominal species; especially the species associated with a particular specific name, as distinct from a species or subspecies subsequently distinguished from it.
2 Geology and Palaeontology. A fossil species which gives its name to a stratigraphic zone of which it is characteristic.
Origin
1950s; earliest use found in Quarterly Review of Biology. From nominate + species.