The original Mac Key classification of Triticum appeared in the 1966 proceedings volume for the 2nd International Wheat Genetics Symposium [reference and classification]. In 1975, Mac Key offered a revised version in an oral presentation at the 12th Botanical Congress held in Leningrad [St. Petersburg]. Because the Congress Proceedings did not include his article, Mac Key published his revised treatment in a 1977 proceedings volume for a relatively obscure symposium held in Bari, Italy [see references] and again in 1988 [see references] in the research journal Biologisches Zentralblatt. The 1988 publication is used here as the official citation of the current Mac Key Triticum classification. The revised 1988 classification added Triticum urartu and changed the names T. turgidum subsp. paleocolchicum to T. turgidum subsp. georgicum, T. timopheevii subsp. araraticum to T. timopheevii subsp. armeniacum, and changed the section assignment of T. zhukovskyi. It is presented here with corrections in authority citations.
| Section Monococca Flaksb. |
| Triticum monococcum L. |
| subsp. monococcum |
| subsp. boeoticum (Boiss.) Á.Löve & D.Löve |
| var. aegilopoides (Link) MacKey |
| var. thaoudar (Reuter in Bourg. ex Hausskn.) Percival |
| Triticum urartu Tumanian ex Gandilyan |
| Section Dicoccoidea Flaksb. |
| Triticum turgidum L. |
| subsp. turgidum |
| conv. turgidum |
| conv. durum (Desf.) MacKey |
| conv. turancium (Jakubz.) MacKey |
| conv. polonicum (L.) MacKey |
| subsp. carthlicum (Nevski in Kom.) Á.Löve & D.Löve. |
| subsp. dicoccum (Schrank ex Schübler) Thell. |
| subsp. georgicum (Dekapr. & Menabde) MacKey |
| subsp. dicoccoides (Körn. ex Asch. & Graebner) Thell. |
| Triticum timopheevii (Zhuk.) Zhuk. |
| subsp. timopheevii |
| subsp. armeniacum (Jakubz.) MacKey |
| Section Speltoidea Flaksb. |
| Triticum aestivum L. |
| subsp. aestivum |
| subsp. compactum (Host) MacKey |
| subsp. macha (Dekapr. & Menabde) MacKey |
| subsp. sphaerococcum (Percival) MacKey |
| Triticum zhukovskyi Menabde & Ericzjan |