This helps maintain a clear chain of nomenclature and prevents confusion about the ultimate source of the name.
[7] The term "basionym" is used in botany only for the circumstances where a previous name exists with a useful description, and the International Code of Nomenclature for algae, fungi, and plants (ICNafp) does not require a full description with the new name.
Prior to 1 January 1953, the requirements for referencing basionyms were less stringent: an indirect reference to a basionym or replaced synonym was sufficient for valid publication of a new combination, name at new rank, or replacement name.
The species was originally named Pinus abies by Carl Linnaeus and so the author citation of the basionym is simply "L." Later on, botanist Gustav Karl Wilhelm Hermann Karsten decided this species should not be grouped in the same genus (Pinus) as the pines, so he transferred it to the genus Picea (the spruces).
The new name Picea abies is combinatio nova, a new combination (abbreviated comb.
Claude Weber did not consider the family name Malaceae Small to be taxonomically appropriate, so he created the name Maloideae at the rank of subfamily, referring to the original description of the family, and using the same type.
[10] This change of rank from family to subfamily is an example of status novus (abbreviated stat.