Re: squalens, sambucina etc (a bit long) (was Iris pallida cultivars & nomenclatural question)

---

Article H.2

H.2.1. A hybrid between named taxa may be indicated by placing the multiplication sign between the names of the taxa; the whole _expression_ is then called a hybrid formula.

Ex. 1. Agrostis L. . × Polypogon Desf.; Agrostis stolonifera L. × Polypogon monspeliensis (L.) Desf.; Salix aurita L. × S. caprea L.; Mentha aquatica L. × M. arvensis L. × M. spicata L.; Polypodium vulgare subsp. prionodes (Asch.) Rothm. × subsp. vulgare; Tilletia caries (Bjerk.) Tul. × T. foetida (Wallr.) Liro.

Recommendation H.2A

H.2A.1. It is usually preferable to place the names or epithets in a formula in alphabetical order. The direction of a cross may be indicated by including the sexual symbols ({o+}: female;{o!}: male) in the formula, or by placing the female parent first. If a non-alphabetical sequence is used, its basis should be clearly indicated.

Article H.3

H.3.1. Hybrids between representatives of two or more taxa may receive a name. For nomenclatural purposes, the hybrid nature of a taxon is indicated by placing the multiplication sign × before the name of an intergeneric hybrid or before the epithet in the name of an interspecific hybrid, or by prefixing the term "notho-" (optionally abbreviated "n-") to the term denoting the rank of the taxon (see Art. 3.2 and 4.4). All such taxa are designated nothotaxa.

Ex. 1. (The putative or known parentage is found in Art. H.2 Ex. 1.) ×Agropogon P. Fourn. (1934); ×Agropogon littoralis (Sm.) C. E. Hubb. (1946); Salix ×capreola Andersson (1867); Mentha ×smithiana R. A. Graham (1949); Polypodium vulgare nothosubsp. mantoniae (Rothm.) Schidlay (in Futák, Fl. Slov. 2: 225. 1966).

H.3.2. A nothotaxon cannot be designated unless at least one parental taxon is known or can be postulated.

H.3.3. For purposes of homonymy and synonymy the multiplication sign and the prefix "notho-" are disregarded.

Ex. 2. ×Hordelymus Bachteev & Darevsk. (1950) (= Elymus L. × Hordeum L.) is a later homonym of Hordelymus (K. Jess.) K. Jess. (1885).

Note 1. Taxa which are believed to be of hybrid origin need not be designated as nothotaxa.

Ex. 3. The true-breeding tetraploid raised from the artificial cross Digitalis grandiflora L. × D. purpurea L. may, if desired, be referred to as D. mertonensis B. H. Buxton & C. D. Darl. (1931); Triticum aestivum L. (1753) is treated as a species although it is not found in nature and its genome has been shown to be composed of those of T. dicoccoides (Körn.) Körn., T. speltoides (Tausch) Gren. ex K. Richt., and T. tauschii (Coss.) Schmalh.; the taxon known as Phlox divaricata subsp. laphamii (A. W. Wood) Wherry (in Morris Arbor. Monogr. 3: 41. 1955) is believed by Levin (in Evolution 21: 92-108. 1967) to be a stabilized product of hybridization between P. divaricata L. subsp. divaricata and P. pilosa subsp. ozarkana Wherry; Rosa canina L. (1753), a polyploid believed to be of ancient hybrid origin, is treated as a species.

Recommendation H.3A

H.3A.1. The multiplication sign in the name of a nothotaxon should be placed against the initial letter of the name or epithet. However, if the mathematical symbol is not available and the letter "x" is used instead, a single letter space may be left between it and the epithet if this helps to avoid ambiguity. The letter "x" should be in lower case.

Article H.4

H.4.1. When all the parent taxa can be postulated or are known, a nothotaxon is circumscribed so as to include all individuals (as far as they can be recognized) derived from the crossing of representatives of the stated parent taxa (i.e. not only the Fl but subsequent filial generations and also back-crosses and combinations of these). There can thus be only one correct name corresponding to a particular hybrid formula; this is the earliest legitimate name (see Art. 6.3) in the appropriate rank (Art. H.5), and other names to which the same hybrid formula applies are synonyms of it.

Ex. 1. The names Oenothera ×wienii Renner ex Rostanski (1977) and O. ×drawertii Renner ex Rostanski (1966) are both considered to apply to the hybrid O. biennis L. × O. villosa Thunb. subsp. villosa; the types of the two nothospecific names are known to differ by a whole gene complex; nevertheless, the later name is treated as a synonym of the earlier.

Note 1. Variation within nothospecies and nothotaxa of lower rank may be treated according to Art. H.12 or, if appropriate, according to the International code of nomenclature for cultivated plants.

Article H.5

H.5.1. The appropriate rank of a nothotaxon is that of the postulated or known parent taxa.

H.5.2. If the postulated or known parent taxa are of unequal rank the appropriate rank of the nothotaxon is the lowest of these ranks.

Note 1. When a taxon is designated by a name in a rank inappropriate to its hybrid formula, the name is incorrect in relation to that hybrid formula but may nevertheless be correct, or may become correct later (see also Art. 52 Note 3).

Ex. 1. The combination Elymus ×laxus (Fr.) Melderis & D. C. McClint. (1983), based on Triticum laxum Fr. (1842), was published for hybrids with the formula E. farctus subsp. boreoatlanticus (Simonet & Guin.) Melderis × E. repens (L.) Gould, so that the combination is in a rank inappropriate to the hybrid formula. It is, however, the correct name applicable to all hybrids between E. farctus (Viv.) Melderis and E. repens.

Ex. 2. Radcliffe-Smith incorrectly published the nothospecific name Euphorbia ×cornubiensis Radcl.-Sm. (1985) for E. amygdaloides L. × E. characias subsp. wulfenii (W. D. J. Koch) Radcl.-Sm., although the correct designation for hybrids between E. amygdaloides and E. characias L. is E. ×martini Rouy (1900); later, he remedied his mistake by publishing the combination E. ×martini nothosubsp. cornubiensis (Radcl.-Sm.) Radcl.-Sm. (in Taxon 35: 349. 1986). However, the name E. ×cornubiensis is potentially correct for hybrids with the formula E. amygdaloides × E. wulfenii W. D. J. Koch.

Recommendation H.5A

H.5A.1. When publishing a name of a new nothotaxon at the rank of species or below, authors should provide any available information on the taxonomic identity, at lower ranks, of the known or postulated parent plants of the type of the name.

Article H.6

H.6.1. A nothogeneric name (i.e. the name at generic rank for a hybrid between representatives of two or more genera) is a condensed formula or is equivalent to a condensed formula.

H.6.2. The nothogeneric name of a bigeneric hybrid is a condensed formula in which the names adopted for the parental genera are combined into a single word, using the first part or the whole of one, the last part or the whole of the other (but not the whole of both) and, optionally, a connecting vowel.

Ex. 1. ×Agropogon P. Fourn. (1934) (= Agrostis L. × Polypogon Desf.); ×Gymnanacamptis Asch. & Graebn. (1907) (= Anacamptis Rich. × Gymnadenia R. Br.); ×Cupressocyparis Dallim. (1938) (= Chamaecyparis Spach × Cupressus L.); ×Seleniphyllum G. D. Rowley (1962) (= Epiphyllum Haw. × Selenicereus (A. Berger) Britton & Rose).

Ex. 2. ×Amarcrinum Coutts (1925) is correct for Amaryllis L. × Crinum L., not "×Crindonna". The latter formula was proposed by Ragionieri (1921) for the same nothogenus, but was formed from the generic name adopted for one parent (Crinum) and a synonym (Belladonna Sweet) of the generic name adopted for the other (Amaryllis). Being contrary to Art. H.6, it is not validly published under Art. 32.1(b).

Ex. 3. The name ×Leucadenia Schltr. (1919) is correct for Leucorchis E. Mey. × Gymnadenia R. Br., but if the generic name Pseudorchis Ség. is adopted instead of Leucorchis, ×Pseudadenia P. F. Hunt (1971) is correct.

Ex. 4. Boivin (1967) published ×Maltea for what he considered to be the intergeneric hybrid Phippsia (Trin.) R. Br. × Puccinellia Parl. As this is not a condensed formula, the name cannot be used for that intergeneric hybrid, for which the correct name is ×Pucciphippsia Tzvelev (1971). Boivin did, however, provide a Latin description and designate a type; consequently, Maltea B. Boivin is a validly published generic name and is correct if its type is treated as belonging to a separate genus, not to a nothogenus.

H.6.3. The nothogeneric name of an intergeneric hybrid derived from four or more genera is formed from the name of a person to which is added the termination -ara; no such name may exceed eight syllables. Such a name is regarded as a condensed formula.

Ex. 5. ×Beallara Moir (1970) (=Brassia R. Br. × Cochlioda Lindl. × Miltonia Lindl. × Odontoglossum Kunth).

H.6.4. The nothogeneric name of a trigeneric hybrid is either (a) a condensed formula in which the three names adopted for the parental genera are combined into a single word not exceeding eight syllables, using the whole or first part of one, followed by the whole or any part of another, followed by the whole or last part of the third (but not the whole of all three) and, optionally, one or two connecting vowels, or (b) a name formed like that of a nothogenus derived from four or more genera, i.e., from a personal name to which is added the termination -ara.

Ex. 6. ×Sophrolaeliocattleya Hurst (1898) (= Cattleya Lindl. × Laelia Lindl. × Sophronitis Lindl.); ×Vascostylis Takakura (1964) (= Ascocentrum Schltr. ex J. J. Sm. × Rhynchostylis Blume × Vanda W. Jones ex R. Br.); ×Rodrettiopsis Moir (1976) (= Comparettia Poepp. & Endl. × Ionopsis Kunth × Rodriguezia Ruiz & Pav.); ×Devereuxara Kirsch (1970) (= Ascocentrum Schltr. ex J. J. Sm. × Phalaenopsis Blume × Vanda W. Jones ex R. Br.).

Recommendation H.6A

H.6A.1. When a nothogeneric name is formed from the name of a person by adding the termination -ara, that person should preferably be a collector, grower, or student of the group.

Article H.7

H.7.1. The name of a nothotaxon which is a hybrid between subdivisions of a genus is a combination of an epithet, which is a condensed formula formed in the same way as a nothogeneric name (Art. H.6.2), with the name of the genus.

Ex. 1. Ptilostemon nothosect. Platon Greuter (in Boissiera 22: 159. 1973), comprising hybrids between P. sect. Platyrhaphium Greuter and P. sect. Ptilostemon; P. nothosect. Plinia Greuter (in Boissiera 22: 158. 1973), comprising hybrids between P. sect. Platyrhaphium and P. sect. Cassinia Greuter.

Article H.8

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 Holttum (1958) (Arachnis × Renanthera × Vanda).

Article H.9

H.9.1. In order to be validly published, the name of a nothogenus or of a nothotaxon with the rank of subdivision of a genus (Art. H.6 and H.7) must be effectively published (see Art. 29, 30, 31) with a statement of the names of the parent genera or subdivisions of genera, but no description or diagnosis is necessary, whether in Latin or in any other language.

Ex. 1. Validly published names: ×Philageria Mast. (1872), published with a statement of parentage, Lapageria Ruiz & Pav. × Philesia Comm. ex Juss.; Eryngium nothosect. Alpestria Burdet & Miège, pro sect. (in Candollea 23: 116. 1968), published with a statement of its parentage, E. sect. Alpina H. Wolff × E. sect. Campestria H. Wolff; ×Agrohordeum A. Camus (1927) (= Agropyron Gaertn. × Hordeum L.), of which ×Hordeopyron Simonet (1935, "Hordeopyrum") is a later synonym.

Note 1. Since the names of nothogenera and nothotaxa with the rank of a subdivision of a genus are condensed formulae or treated as such, they do not have types.

Ex. 2. The name ×Ericalluna Krüssm. (1960) was published for plants ("×E. bealeana", nom. inval.) which were thought to be the product of the cross Calluna vulgaris (L.) Hull × Erica cinerea L. If it is considered that these are not hybrids, but are variants of E. cinerea, the name ×Ericalluna Krüssm. remains available for use if and when known or postulated plants of Calluna Salisb. × Erica L. should appear.

Ex. 3. ×Arabidobrassica Gleba & Fr. Hoffm. (in Naturwissenschaften 66: 548. 1979), a nothogeneric name which was validly published with a statement of parentage for the result of somatic hybridization by protoplast fusion of Arabidopsis thaliana (L.) Heynh. with Brassica campestris L., is also available for intergeneric hybrids resulting from normal crosses between Arabidopsis Heynh. and Brassica L., should any be produced.

Note 2. However, names published merely in anticipation of the existence of a hybrid are not validly published under Art. 34.1(b).

Article H.10

H.10.1. Names of nothotaxa at the rank of species or below must conform with the provisions (a) in the body of the Code applicable to the same ranks and (b) in Art. H.3. Infringements of Art. H.3.1. are treated as errors to be corrected.

Ex. 1. The nothospecies name Melampsora ×columbiana G. Newc. (in Mycol. Res. 104: 271. 2000) was validly published, with a Latin description and designation of a holotype, for the hybrid between M. medusae Thüm. and M. occidentalis H. S. Jacks.

H.10.2. Taxa previously published as species or infraspecific taxa which are later considered to be nothotaxa may be indicated as such, without change of rank, in conformity with Art. 3 and 4 and by the application of Art. 50 (which also operates in the reverse direction).

H.10.3. The following are considered to be formulae and not true epithets: designations consisting of the epithets of the names of the parents combined in unaltered form by a hyphen, or with only the termination of one epithet changed, or consisting of the specific epithet of the name of one parent combined with the generic name of the other (with or without change of termination).

Ex. 2. The designation Potentilla "atrosanguinea-pedata" published by Maund (in Bot. Gard. 5: No. 385, t. 97. 1833) is considered to be a formula meaning Potentilla atrosanguinea Lodd. ex D. Don × P. pedata Nestl.

Ex. 3. Verbascum "nigro-lychnitis" (Schiede, Pl. Hybr.: 40. 1825) is considered to be a formula, Verbascum lychnitis L. × V. nigrum L.; the correct binary name for this hybrid is Verbascum ×schiedeanum W. D. J. Koch (1844).

Ex. 4. The following names include true epithets (but see Rec. H.10A): Acaena ×anserovina Orchard (1969) (from A. anserinifolia (J. R. Forst. & G. Forst.) J. Armstr. and A. ovina A. Cunn.); Micromeria ×benthamineolens Svent. (1969) (from M. benthamii Webb & Berthel. and M. pineolens Svent.).

Note 1. Since the name of a nothotaxon at the rank of species or below has a type, statements of parentage play a secondary part in determining the application of the name.

Ex. 5. Quercus ×deamii Trel. (in Mem. Natl. Acad. Sci. 20: 14. 1924) when described was considered as the cross Q. alba L. × Q. muehlenbergii Engelm. However, progeny grown from acorns from the tree from which the type originated led Bartlett to conclude that the parents were in fact Q. macrocarpa Michx. and Q. muehlenbergii. If this conclusion is accepted, the name Q. ×deamii applies to Q. macrocarpa × Q. muehlenbergii, and not to Q. alba × Q. muehlenbergii.

Recommendation H.10A

H.10A.1. In forming epithets for names of nothotaxa at the rank of species and below, authors should avoid combining parts of the epithets of the names of the parents.

Recommendation H.10B

H.10B.1. When contemplating the publication of new names for hybrids between named infraspecific taxa, authors should carefully consider whether they are really needed, bearing in mind that formulae, though more cumbersome, are more informative.

Article H.11

H.11.1. The name of a nothospecies of which the postulated or known parent species belong to different genera is a combination of a nothospecific epithet with a nothogeneric name.

Ex. 1. ×Heucherella tiarelloides (Lemoine & E. Lemoine) H. R. Wehrh. is considered to have originated from the cross between a garden hybrid of Heuchera L. and Tiarella cordifolia L. (see Stearn in Bot. Mag. 165: ad t. 31. 1948). Its original name, Heuchera ×tiarelloides Lemoine & E. Lemoine (1912), is therefore incorrect.

Ex. 2. When Orchis fuchsii Druce was renamed Dactylorhiza fuchsii (Druce) Soó the name for its hybrid with Coeloglossum viride (L.) Hartm., ×Orchicoeloglossum mixtum Asch. & Graebn. (1907), became the basis of the necessary new combination ×Dactyloglossum mixtum (Asch. & Graebn.) Rauschert (1969).

H.11.2. The final epithet in the name of an infraspecific nothotaxon of which the postulated or known parental taxa are assigned to different species, may be placed subordinate to the name of a nothospecies (but see Rec. H.10B).

Ex. 3. Mentha ×piperita L. nothosubsp. piperita (= M. aquatica L. × M. spicata L. subsp. spicata); Mentha ×piperita nothosubsp. pyramidalis (Ten.) Harley (in Kew Bull. 37: 604. 1983) (= M. aquatica L. × M. spicata subsp. tomentosa (Briq.) Harley).

Article H.12

H.12.1. Subordinate taxa within nothospecies may be recognized without an obligation to specify parent taxa at the subordinate rank. In this case non-hybrid infraspecific categories of the appropriate rank are used.

Ex. 1. Mentha ×piperita f. hirsuta Sole; Populus ×canadensis var. serotina (R. Hartig) Rehder and P. ×canadensis var. marilandica (Poir.) Rehder (see also Art. H.4 Note 1).

Note 1. As there is no statement of parentage at the rank concerned there is no control of circumscription at this rank by parentage (compare Art. H.4).

Note 2. It is not feasible to treat subdivisions of nothospecies by the methods of both Art. H.10 and H.12.1 at the same rank.

H.12.2. Names published at the rank of nothomorph are treated as having been published as names of varieties (see Art. 50).