quinarian

from The Century Dictionary.

• Quinary, as a system of classification; classified in sets of five.
• noun In zoology, one who proposed, practised, or taught the quinary system of classification; an adherent of the quinary system.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Divided into five parts
• adjective taxonomy Describing a system of classification based on the quinary system
• noun An advocate of this method of classification