H.8.1. When the name or the epithet in the name of a nothotaxon is a condensed formula (Art. H.6 and H.7), the parental names used in its formation must be those which are correct for the particular circumscription, position, and rank accepted for the parental taxa.
Ex. 1. If the genus Triticum L. is interpreted on taxonomic grounds as including Triticum (s. str.) and Agropyron Gaertn., and the genus Hordeum L. as including Hordeum (s. str.) and Elymus L., then hybrids between Agropyron and Elymus as well as between Triticum (s. str.) and Hordeum (s. str.) are placed in the same nothogenus, Tritordeum Asch. & Graebn. (1902). If, however, Agropyron is separated generically from Triticum, hybrids between Agropyron and Hordeum (s. str. or s. lat.) are placed in the nothogenus Agrohordeum A. Camus (1927). Similarly, if Elymus is separated generically from Hordeum, hybrids between Elymus and Triticum (s. str. or s. lat.) are placed in the nothogenus Elymotriticum P. Fourn. (1935). If both Agropyron and Elymus are given generic rank, hybrids between them are placed in the nothogenus Agroelymus A. Camus (1927); Tritordeum is then restricted to hybrids between Hordeum (s. str.) and Triticum (s. str.), and hybrids between Elymus and Hordeum are placed in Elyhordeum Mansf. ex Tsitsin & Petrova (1955), a substitute name for Hordelymus Bachteev & Darevsk. (1950) non Hordelymus (K. Jess.) K. Jess. (1885).
H.8.2. Names ending in -ara for nothogenera, which are equivalent to condensed formulae (Art. H.6.3-4), are applicable only to plants which are accepted taxonomically as derived from the parents named.
Ex. 2. If Euanthe Schltr. is recognized as a distinct
genus, hybrids simultaneously involving its only species, E.
sanderiana (Rchb.) Schltr., and the three genera Arachnis
Blume, Renanthera Lour., and Vanda W. Jones ex R.
Br. must be placed in Cogniauxara Garay & H. R. Sweet
(1966); if, on the other hand, E. sanderiana is included
in Vanda, the same hybrids are placed in Holttumara
anon. (1958) (Arachnis Renanthera Vanda).