species (taxonomic)

https://doi.org/10.1351/goldbook.S05786
A taxonomic subdivision of a genus; a group of closely related, morphologically and physiologically similar individuals.
Source:
PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 166 (https://doi.org/10.1351/pac199264010143)