Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1

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1 Phytocoenologia, 41 (1), Stuttgart, April 26, 2011 Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1 by Wolfgang WILLNER, Georg GRABHERR, Vienna, Jens PALLAS, Münster and Heinrich E. WEBER, Bramsche Abstract: With the 3 rd edition of the International Code of Phytosociological Nomenclature, a special Committee was established to faciliate and accelerate the decision of the Nomenclature Commission on submitted proposals for nomina ambigua, nomina inversa, nomina mutata, and nomina conservanda. Here we present the first report of this Committee. In the first part of the paper, a short overview of the major problems related with each of the four categories is given. In the second part, 19 proposals are discussed together with a recommendation whether the proposal should be accepted or rejected. Authors who wish to submit a proposal to the Nomenclature Commission are asked to use this report as a guideline. Keywords: Nomenclature, nomen ambiguum, nomen inversum, nomen mutatum, nomen conservandum, syntaxonomy. Introduction The International Code of Phytosociological Nomenclature (in the following referred to as the Code ) is based on two main principles: the principle of priority, and the type method (Weber et al. 2000). Both are established to promote stability and to ensure the unambiguous application of names of syntaxa. In order to avoid the maintenance or re-introduction of misleading names or the rejection of well-known and long-accepted ones due to the rigid application of the rules, the Code provides the possibility to establish nomina ambigua (Art. 36), nomina inversa (Art. 42), nomina mutata (Art. 45), and nomina conservanda (Art. 52). The application of these categories requires a specific set of actions by the users of the Code as well as the Nomenclature Commission which is regulated in the respective articles. The publication of a nomen ambiguum, nomen inversum, nomen mutatum or nomen conservandum remains provisional until the Nomenclature Commission accepts or rejects it. To faciliate and accelerate the decision of the Nomenclature Commission, a special Committee was established, and authors were asked to send copies of their proposals to this board. Instructions for proposals and a list of possibly needed supporting documents are given in the Code (Weber et al. 2000: 764). The adopted or rejected proposals are to be published as appendices of the Code, and after the publication of a nomen ambiguum, nomen inversum, nomen mutatum or nomen conservandum in one of these appendices, its application is obligatory. That is theory. In practice, however, things have developed in a slightly different way: So far, only few authors have sent proposals to the Committee, and in most cases the documents enclosed were not sufficient for a definite decision. Meanwhile, the phytosociological literature is littered with provisional nomina ambigua proposita, nomina inversa proposita, nomina mutata proposita, and nomina conservanda proposita, mostly without or with only marginal discussion of the reasons for the proposals. Obviously, most authors are not aware of the many pitfalls in the application of the articles mentioned above. In the following, we want to give a short overview of the major problems related with each of the four categories. Subsequently, we list and discuss some proposals submitted to the Committee, together with a recommendation whether the proposal should be accepted or rejected. The present paper is intended to serve as a guideline to authors who wish to submit a proposal to the Nomenclature Commission. The author of the proposal should give basic information on the syntaxa and names involved, including considerations of validity, date and typification. A statement of the cases both for and against rejection/alteration/conservation must be given. If there are different options to handle the matter, proposers should explain their implications and state the reasons for their own preference. Proposals not matching these standards cannot be treated by the Committee. The list of submitted proposals will be continued in subsequent reports. Rejection, correction, and conservation of syntaxonomic names A validly published name according to the formal requirements of the Code must not be rejected or corrected because it is considered to be less adequate 2011 Gebrüder Borntraeger, Stuttgart, Germany DOI: / X/2011/ X/11/ $ 5.40

2 60 W. Willner et al. for the syntaxon (Art. 29a, Art. 40a). However, the Code provides also some exceptions to this general rule (see Art. 29b, Art. 35, Art. 41). For the purpose of the present paper, Art. 43 and 44 are of special relevance: When the name of a syntaxon is based on a misidentification of the name-giving taxon or on a taxon name that is used in an incorrect sense, then the syntaxon name must be corrected (Art. 43). A correction in the sense of this article also occurs when the name of an aggregate species is replaced by the name of a narrowly defined species within that aggregate. Such a case is therefore not eligible as nomen mutatum (see below). It should be noticed that Art. 43 does not allow to replace a species name by the name of an infraspecific taxon or vice versa. A special case of a nomen correctum is regulated in Art. 44: When a name-giving taxon name is rejected as a later homonym according to the rules of the International Code of Botanical Nomenclature (ICBN, McNeill et al. 2007), it must be replaced by a different name of the same taxon. The first effectively published choice must be followed. In all cases mentioned so far, no action by the Nomenclature Commission is necessary. Authors should carefully check whether a syntaxon name is validly published and legitimate before publishing a nomen correctum. In the case of syntaxa above the association rank, the validity of all subordinate syntaxa which have been quoted in the original diagnosis (at least of the type-syntaxon) must be proved. The same is true, of course, for proposals concerning a nomen ambiguum, nomen inversum, nomen mutatum or nomen conservandum. A considerable portion of the submitted nomina mutata proposita turned out to be invalid according to Art. 2b, 3a, 3b or 5 after checking the enclosed copies of original diagnoses. Nomina ambigua Art. 36 of the Code is frequently used to get rid of names which, due to the principle of priority, threaten a well-established but younger name. In most cases, however, Art. 52 (nomina conservanda) would be the more adequate one to handle the problem. In fact, all cases where Art. 36 is applicable can also be solved with Art. 52. The concept of nomina ambigua is restricted to cases where a name has been used by most authors in a false sense that excludes its type. Therefore, all cases where the name-bearing type was not excluded by the vast majority of authors, are not acceptable as nomina ambigua, regardless of how misleading the name may be or how improperly it was used in the past. Nomina inversa When a syntaxon name is formed from two taxon names of which one is dominant or belongs to the highest stratum, then the name of that taxon has to appear on the second place (Art. 10b). The concept of nomina inversa is somewhat different from the other three ones discussed here because the Code requires that names not formed according to the mentioned rule (e.g. the name Querco-Lithospermetum Braun-Blanquet 1929) must be inverted (Art. 42). The latter article, however, requires to send a proposal with reasons for the corresponding inversion to the Nomenclature Commission. At the same time, Art. 10b states that names published on or after and not being in accordance with the rule, are even invalid (see also Art. 3k). Obviously, the Code is logically inconsistent at this point: If there is an objective measure whether the name-giving taxa have been placed in the right order or not, an automatic inversion of incorrect names would be appropriate, and no action of the Nomenclature Commission would be necessary (analogous to Art. 41 which regulates the correction of orthographic errors). On the other hand, if such decision involved subjective choices, no objective judgment on the validity of new names would be possible. Problems arise especially from cases where the two name-giving taxa belong to the same stratum and none of them is clearly the dominant one. The next edition of the Code should provide an unambiguous rule for the correct order of name-giving taxa, while nomina inversa should be reserved for cases in which a name is to be conserved in a form contrary to this general rule. For the time being, decision on proposals for nomina inversa will be postponed. Nomina mutata Art. 45 of the Code provides the possibility to adapt syntaxon names to changes in taxonomic nomenclature. If a syntaxon name is formed from a taxon name that is no longer accepted as correct name in the most important taxonomic and floristic literature of the past 20 years, it may be proposed with corresponding reasons to the Nomenclature Commission to adapt this name to the contemporary taxonomic nomenclature. The most obvious problem concerning this article is to decide on what is the most important taxonomic and floristic literature of the past 20 years. Certainly, all national floras have to be included. However, in some countries floras older than 20 years are still in use. Should they be neglected? And what about regional floras and taxonomic monographs? Authors of proposals for nomina mutata must carefully check why the formerly used taxon name is put into synonymy. In general, nomenclatural changes can be divided into two main groups: (1) changes due to purely nomenclatural (i.e. formal) reasons, (2) changes due to new taxonomic concepts (i.e. scientific reasons). Among the first category, priority is the most frequent reason, but also conservation and rejection of taxon names as nomina conservanda resp. nomina rejicienda according to the ICBN. Special at-

3 Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1 61 tention has to be given to cases where a taxon name is rejected as a later homonym, because in such cases correction of the syntaxon name according to Art. 44 must be applied (see e.g. proposal 10 11). If a taxon name has been replaced because it was used in a way that excludes its nomenclatural type, a correction according to Art. 43 is necessary (see e.g. proposal 15). Apart from such cases, a nomen mutatum propositum will be accepted if it can be shown that the nomenclatural change of the taxon name is due to purely formal reasons, even if some floras continue to use the incorrect taxon name (see e.g. proposal 5). More difficult is the situation if a nomenclatural change is due to new taxonomic concepts because the taxonomic treatment of plant taxa is partly subjected to the personal judgement of authors. The same taxon may be treated as species by one author and as subspecies (or even lower rank) by another. Different opinions on the rank of a plant taxon are therefore a major source of nomenclatural change. However, this is usually not a case for Art. 45 but for Art. 43 which provides the possibility to correct a syntaxon name in such way that the name of a broadly defined species is replaced by the name of a narrowly defined species. Recommendation 43A asks authors not to proceed with a correction when the specific rank is not regularly attributed to a taxon in current floras, but it remains unclear whether a validly published nomen correctum has to be followed even if the narrowly defined species used for the correction is not generally accepted. Some members of the Commitee argue that in such a case the correction may be ignored and the original syntaxon name be maintained. Another and perhaps the most frequent source for changes of species names are changes in the circumscription of genera. In some cases, such changes involve practically no subjective element and are generally accepted after a while. E.g. the transfer of the species Asperula odorata to the genus Galium was generally accepted, and the species is now treated under the name Galium odoratum by all recent floras. In such a case we can assume that the old name has disappeared forever, and the mutation of the syntaxon name Asperulo odoratae-fagetum into Galio odorati-fagetum can be accepted without hesitation (see proposal 18). However, in many cases the delimitation of genera is at least partly the personal view of the author, whether he prefers a broader genus concept or a narrower one. Consensus among floras has hardly ever been achieved, and there is not much hope that this will be changed in the future. There are countless examples for varying treatments of genera, e.g. Phyllitis (included in Asplenium or not), Hepatica (included in Anemone or not), Pseudolysimachion (included in Veronica or not) etc. etc. In some cases, the taxonomic treatment of genera has been oscillating between the narrow and the broad concept for many decades, and even if all floras have followed a certain concept for 20 years (which is, however, very unlikely), there is no guarantee that the pendulum won t move in the opposite direction once again in the near future. In particular, the tradition of genera concepts varies between different countries (with a general trend from more broadly defined genera in Western Europe to more narrowly defined ones in eastern Europe). Nomina conservanda The possibility to protect names irrespective of their priority was newly introduced in the 3 rd edition of the Code, and it has become quite popular to use provisional nomina conservanda proposita in the phytosociological literature. According to Art. 52, a name must fulfil three criteria in order to be eligible as nomen conservandum: (1) It must be commonly used in the literature, (2) it must be validly published, and (3) it must be applied in accordance with the nomenclatural type. In analogy to Botanical Nomenclature, accepted nomina conservanda will be automatically conserved against all other names in the same rank based on the same type (homotypic synonyms), against all earlier homonyms as well as against those synonyms which will be specified in the Appendix of the Code. The simplest case is that a commonly used, validly published name is to be protected against an earlier but not commonly used one. However, it is not unusual that the same syntaxon has two or more synomyms being in current use (especially when the syntaxon occurs in various countries). In some cases, there may be good reasons to deviate from the principle of priority, e.g. because the older name would be extremely misleading (which might be the case if a name was described for a syntaxon which, after revision, has got a very different circumscription), or because the name applied by the majority of authors should be preserved. Such a proposal, however, must be discussed with all pros and cons (see e.g. proposal 18), and in case of doubt the principle of priority outweighs all other considerations. According to the current Code, conservation of a commonly used name is not possible if it turns out to be invalid. As an exception, association names of the Uppsala School published before are considered as validly published if accepted as nomina conservanda (see also proposal 19). A special problem arises from names accompanied by an original diagnosis that does not clearly fulfil the requirements of Art. 2b. Numerous names of alliances, orders, and classes have been published in the older days lacking bibliographically complete references for the names of syntaxa of subordinate ranks (e.g. Braun-Blanquet & Tüxen 1943, Klika & Hadač 1944, Tüxen 1950, 1955, Eggler 1952, Doing 1962, Oberdorfer et al. 1967). Although the original diagnosis of the cited names can be inferred in many cases (Pallas 1997: 247, Willner & Grabherr 2007: 221ff), the majority of authors follow a rather formalistic interpretation of Art. 2b, rejecting all of those names as nomina nuda. Among the various problems that frequently

4 62 W. Willner et al. arise from later validations are (1) typification with rather untypical relevés or syntaxa, (2) higher syntaxa based on later homonyms because of multiple validations of the same name, and (3) an inflation of ex in the author citations (see Recommendation 51A). The validating authors were usually not aware of the fact that the name which they were using had not been validly published (or could not be aware of it because the Code had not yet been established at that time). Many cases could be solved by an amendment of Art. 2b providing different regulations for names published before and after the 1 st ed. of the Code (see also Art and 32.6 ICBN, McNeill et al. 2007). However, even if such an amendment is accepted in the next edition of the Code, doubtful cases will arise which need action by the Nomenclature Commission in order to stabilise the application of names. List of proposals (1) To reject the name Luzulo-Quercetum sessilis Hilitzer 1932 nom. amb. prop. Proposed by E. Oberdorfer (letter to J. Moravec, ). Luzulo-Quercetum sessilis Hilitzer 1932: 9. Typus: Hilitzer l.c. (Holotypus). This name was published by Hilitzer (1932) in the form asociace Quercus sessilis-luzula nemorosa (albida) with one single relevé. It is used for acidophilous oak woods of a southern-temperate European distribution. Whereas the original diagnosis is quite plain, the form of the name raises several nomenclatural problems. It is formed from the two unaltered plant names Quercus sessilis Ehrh. and Luzula nemorosa.for the latter, the synonym L. albida DC. is given in brackets. Since L. nemorosa E. Mey (= L. albida DC.) is rejected as a later homonym of L. nemorosa Baumg. 1817, a correction of all names based on that plant name is necessary (Art. 44). However, the epitheton in brackets seems to establish two homotypic names of equal age (Luzulo nemorosae-quercetum sessilis and Luzulo albidae- Quercetum sessilis) or may even be interpreted as correction in the sense of Art. 44. In any case, the name is a canditate for a nomen inversum as well as a nomen mutatum (Luzulo luzuloidis-quercetum petraeae nom. invers. et mut. prop.). Hilitzer s name was hardly recognized by the time of its publication. Instead, the name Genisto tinctoriae-quercetum petraeae Klika 1932: 335 (original form: asociace Quercus sessiliflora- Genista tinctoria; Typus: Klika l.c. Tab. p. 336/337, rel. 2, Lectotypus Pallas 1996: 57) was frequently used for the same plant community. Klika (l.c.: 334) identified his association (for which he created several illegitimate alternative names) with the Quercetum medioeuropaeum Braun-Blanquet 1932 nom. illeg. (Art. 34), a community type dominated by Quercus robur rather than by Quercus petraea. In the table, which contains eight relevés, Klika did not distinguish between the two oak species. Knapp (1942: 51) established the name Querceto-Luzuletum nemorosae (not effectively published and without sufficient original diagnosis, Art. 1 & 7), most propably without knowing the earlier name of Hilitzer. In this broad association concept, he included not only the acidophilous oak forests of most parts of Central Europe but also acidophytic beech forests. Knapp published the name Luzulo nemorosae-quercetum effectively not earlier than 1948 (Knapp 1948: 61), but again invalidly, giving the constancy of only three species (Art. 7). The name Luzulo-Quercetum Passarge 1953 (Neotypus Pallas 2002: 151) referred to Knapp and not to Hilitzer s name which was unknown to Passarge in 1953 (pers. comm. Passarge to J. Pallas in 1996, see also reference to Knapp 1948 in Passarge 1953: 551). Oberdorfer followed the concept of Knapp as well in the early years. His Querceto- Luzuletum collinum (1952: 26) was later incorporated into the Melampyro-Fagetum Oberdorfer 1957: 490 (Lectotypus Willner 2002: 409). Confusion might have been caused by R. & Z. Neuhäusl (1967) who knew Hilitzer s diagnosis and tried to force it into one association with Luzulo- Quercetum Passarge However, the diagnosis of Passarge is not too narrow ( zu eng gefaßt, R. & Z. Neuhäusl 1967: 10), but simply refers to a different woodland type than Hilitzer s. Oberdorfer (in litt.) argues that the name Luzulo-Quercetum has become ambiguous since it was used for communities which, according to recent syntaxonomic concepts, belong to different associations. He therefore suggests to reject the name as nomen ambiguum. However, all synoptic treatments of the past 20 years (Pallas 1996: 53 with details, Härdtle et al. 1997, Moravec 1998, Willner & Grabherr 2007) use Hilitzer s name in the correct sense. The original diagnosis of the name Genisto tinctoriae-quercetum petraeae Klika 1932, on the other hand, is unclear and may not even belong to the same association as Hilitzer s name. Considering these facts, the Committee does not recommend the rejection of the name Luzulo-Quercetum sessilis. Votes: 0 pro, 4 contra (not recommended). (2) To mutate the name Stipetalia calamagrostis Oberd. & Seibert 1977 to Achnatheretalia calamagrostis nom. mut. prop. Proposed by J. Izco (see Rivas-Martínez et al. 2002: 247). Stipetalia calamagrostis Oberdorfer & Seibert in Oberdorfer 1977, Süddeutsche Pflanzenges. 1: 59. Typus: Stipion calamagrostis Jenny-Lips ex Seibert in Oberdorfer 1977 ( Stipion calamagrostis Jenny-Lips ex Braun-Blanquet 1948: 38). The order Stipetalia calamagrostis includes thermophilous calcareous scree communities in Europe. The alliance Stipion calamagrostis was es-

5 Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1 63 tablished by Jenny-Lips (1930) together with a validly published association Stipetum calamagrostis Jenny-Lips Unfortunately, he published the name of the alliance provisionally, therefore the name Stipion calamagrostis Jenny-Lips 1930 is invalid (Art. 3b). Rivas-Martínez et al. (2002) suggest that the name was validated by Braun-Blanquet et al. (1952). This conclusion is challanged by the fact that Braun-Blanquet (1948: 38) already published the name Stipion calamagrostis as definitely accepted. But then, the latter work, which was published in several parts (with the references in the last one), has repeatedly raised doubts concerning the requirement of Art. 2b. The name-giving Stipa calamagrostis (L.) Wahlenb. is treated as Achnatherum calamagrostis (L.) P. Beauv. in most floras and check-lists of the last decades (e.g. Ehrendorfer 1973, Tutin et al. 1980). This is a good example for a change of a species name due to a new delimitation of genera. The genus Achnatherum has been included in Stipa in the past, and Hegi s Flora of Central Europe still follows this concept (Conert 1998: 404). While some members of the Committee argued that the majority of authors should be followed in this case, others emphasised that the 3 rd edition of Hegi s Flora is too an important work to be ignored. Votes: 2 pro, 2 contra (not recommended). (3 4) To mutate the names Caricion fuscae Koch 1926 and Caricetalia fuscae Koch 1926 to Caricion nigrae nom. mut. prop. and Caricetalia nigrae nom. mut. prop. Proposed by J. Izco (see Rivas-Martínez et al. 2002: 253f). Caricion fuscae Koch 1926: 20, 65. Typus: Caricetum fuscae Koch 1926 (Lectotypus Art. 20). Caricetalia fuscae Koch 1926: 20, 67. Typus: Caricion fuscae Koch 1926 (Lectotypus Art. 20). The name Caricetalia fuscae is usually used for mire communities on acidic soils (Steiner 1993, Rodwell et al. 2002). It was established by Koch (1926) in his seminal work on the plant communities of northeastern Switzerland. However, Koch used this name in a rather broad sense, including vegetation units today classified within several (usually three) orders. In the original diagnosis, the order comprised two alliances: Caricion fuscae and Rhynchosporion albae. According to Art. 20, the first is the lectotypus of the order. Koch (l.c.: 66) enumerates six associations for Caricion fuscae of which only one, Caricetum fuscae, is retained as part of the alliance in recent syntaxonomical schemes while the other associations are usually classified within Caricion davallianae Klika 1934 and Caricion lasiocarpae Vanden Bergen 1949 (see e.g. Steiner 1993). The nomenclature of the association Caricetum fuscae Koch 1926 is discussed in detail by Dengler et al. (2004: 360). They come to the conclusion that the type relevé of Caricetum fuscae Koch 1926 ( Caricetum fuscae Beger 1922) does not belong to the vegetation unit known as Caricetum goodenowii Braun 1915 in the literature but to a community of moderately base-rich mires which many authors would not even regard as being part of the alliance Caricion fuscae. Therefore, the names Caricetum fuscae, Caricion fuscae and Caricetalia fuscae may be candidates for nomina ambigua. Conserving the name Caricetum fuscae with a different type could be an option as well. However, the Committee does not recommend to submit such a proposal before a large-scale syntaxonomical revision of the mire communities of Europe has been presented. Dengler et al. (2004: 358) also note that according to Kiffe (in Wisskirchen & Haeupler 1998: 127) Carex fusca All. is not identical with the Central European Carex nigra (L.) Reichard. This statement ascribed to Kiffe cannot be confirmed after the study of the given reference. No Votes (not ripe for decision). (5) To mutate the name Limnanthemetum nymphoidis Bellot 1951 to Nymphoidetum peltatae nom. mut. prop. Proposed by J. Izco (see Rivas-Martínez et al. 2002: 269) and by J. Dengler (see Berg et al. 2004: 587). Limnanthemetum nymphoidis Bellot 1951, Trab. Jard. Bot., Santiago de Compostela 4: 14. Typus: nondum selectus? This name is used for a community in nutrient-rich fresh water dominated by Nymphoides peltata (S.G. Gmel.) O. Kuntze ( Limnanthemum nymphoides (L.) Hoffmanns. & Link). It is mainly distributed in submediterranean regions. The name-giving species was originally described as Menyanthes nymphoides L. but then transfered into a separate genus. Since the generic name Nymphoides Ség has priority above Limnanthemum Gmel. 1770, the correct name of the species is Nymphoides peltata. (6) To mutate the name Quercion pubescentisessiliflorae Br.-Bl to Quercion pubescenti-petraeae nom. mut. prop. Proposed by J. Izco (see Rivas-Martínez et al. 2002: 274). Quercion pubescenti-sessiliflorae Braun- Blanquet 1932, Beih. Bot. Centralbl. 49, Ergbd. Drude-Festschr.): 8. Typus: Querceto-Lithospermetum Braun-Blanquet 1932, l.c.: 15 (Lectotypus Chytrý 1997, Folia Geobot. Phytotax. 32: 253). The alliance Quercion pubescenti-sessiliflorae includes thermophilous oak forests of Central and Southern Europe. The name-giving species are Quercus pubescens Willd. and Q. sessiliflora Salisb., the latter being a nom. illeg. Since many decades, all floras use the correct name Q. petraea.

6 64 W. Willner et al. (7) To mutate the name Agropyro-Minuartion peploidis Br.-Bl. & Tx to Agropyro-Honckenyion peploidis nom. mut. prop. Proposed by J. Dengler (see Berg et al. 2004: 587). Agropyro-Minuartion peploidis Braun-Blanquet & Tüxen 1952: 248. Typus: Euphorbio-Agropyretum juncei Braun-Blanquet & Tüxen 1952: 248 (Holotypus). This alliance was described for the pioneer vegetation on coastal foredunes of the European Atlantic coast. The original diagnosis contains only one association which is therefore the holotypus of the alliance name. Braun-Blanquet & Tüxen (1952) published the association and the alliance name with the author citation Tx mskr., indicating that both names had already been ineffectively published by Tüxen in 1945 (Art. 1). The quotation of Tüxen with the word ex is not necessary in this case (Rec. 46D). The name-giving species are Agropyron junceum (L.) P. Beauv. and Minuartia peploides (L.) Hiern ( Honckenya peploides (L.) Ehrh.). The rather narrowly defined genus Honckenya Ehrh. (only two species worldwide) is accepted by most (if not all) recent floras. (8) To mutate the name Convolvuletalia sepium Tx to Calystegietalia sepium nom. mut. prop. Proposed by J. Izco (see Rivas-Martínez et al. 2002: 252) and by J. Dengler (see Berg et al. 2004: 587). Convolvuletalia sepium Tüxen 1950: 161 (nom. illeg., Art. 29b). Typus: Senecionion fluviatilis Tüxen 1950: 162 (nom. illeg., Art. 29b) (Lectotypus Mucina 1993, Die Pflanzenges. Österr. I: 231). The name Convolvuletalia sepium is usually used for semi-natural plant communities of tall perennial herbs on banks of rivers and other water bodies of temperate Europe. The name-giving Convolvulus sepium L. is now classified as Calystegia sepium (L.) R. Br. by most floras. The order Convolvuletalia sepium was established by Tüxen (1950: 161) who included two alliances within this order: Convolvulo-Archangelicion litoralis Tx prov. (nom. inval., Art. 3b) and Senecionion fluviatilis Tx. (1947) For the latter, two synonyms are given: Calystegion sepii Tx. 1947, and Convolvulion sepii Oberdorfer The alliance Calystegion sepii Tüxen 1947: 276 was published with two simultaneously described associations included in the original diagnosis: (1) Convolvulus sepium-cuscuta europea-ass., and (2) Petasites hybridus-aegopodium podagraria-ass.. For the first, Tüxen published a single relevé which should be the holotypus of the association name. However, only one of the two name-giving species (Convolvulus sepium) is present in the relevé whereas Cuscuta europea is only mentioned as being present in other stands of the same community (Tüxen 1947: 130). Therefore, the Convolvulus sepium-cuscuta europea-ass. is invalidly published according to Art. 3f. The description of the second association is accompanied by a table containing two relevés. Both name-giving species of the association (Petasites hybridus and Aegopodium podagraria) are present in the table, whereas the name-giving species of the alliance (Convolvulus sepium Calystegia sepium) is not (which is, however, not necessary for the valid publication of the association). Dengler et al. (2003: 615) argue that the alliance Calystegion sepii Tüxen 1947 is validly published because the original diagnosis of the invalid association name (which contains the name-giving species of the alliance) is nevertheless part of the original diagnosis of the alliance, and therefore the requirement of Art. 3f is fulfilled; however, as the only validly published association, the Petasites hybridus-aegopodium podagraria- Ass. is the holotype of the alliance. Furthermore, Dengler et al. (l.c.) argue that the relevés are not the original diagnosis itself but only form part of it. We do not agree with this point of view. In our opinion, the relevés are the only part of the original diagnosis which is relevant for nomenclatural questions. The diagnosis of an invalid association name must be treated as not published (see Def. IV). Therefore, the Convolvulus sepium-cuscuta europea-ass. as well as the alliance Calystegion sepii are invalidly published. The name Senecion fluviatilis (recte: Senecionion fluviatilis) is mentioned in Tüxen (1947: 152) but it is not clear whether this is considered as synonym of the alliance Calystegion sepii or as a separate alliance. Therefore, the name Senecionion fluviatilis Tüxen 1947 is a nomen nudum and not validly published either. The name Convolvulion sepii Oberdorfer 1949 is also a nomen nudum because no associations are given for the alliance (Oberdorfer 1949: 14). In Tüxen (1950), seven associations are included in the alliance Senecionion fluviatilis: (1) Convolvulus sepium-cuscuta europea-ass. Tx (nom. inval., see above), (2) Aster salignus-angelica archangelica-ass. Tx. et Firbas 1950 (prov.) (nom. inval., Art. 3b), (3) Achillea cartilaginea-cuscuta lupuliformis-ass. (Hueck 1930) Tx. 1950, (4) Cuscuta Gronovii-Brassica nigra-ass. Volk 1950 prov. (nom. inval., Art. 3b), (5) Convolvulus sepium- Asperula aparine-ass. (Steffen 1931) Tx. 1950, (6) Senecio fluviatilis-galega officinalis-ass. (Gogela 1910) Tx prov. (nom. inval., Art. 3b), and (7) Rudbeckia laciniata-solidago canadensis-ass. Tx. et Raabe 1950 prov. (nom. inval., Art. 3b). The validity of associations 3 and 5 may be questioned in the light of Art. 2b: The paper of Tüxen (1950) lacks any bibliography. There is only a general remark on page 96 that most papers can be found in the Bibliographia Phytosociologica (a bibliographic series published by Tüxen), in the bibliography of phytosociological textbooks and in the journal Vegetatio. If we follow a strict interpretation of Art. 2b, the name Senecionion fluviatilis Tüxen 1950 can not be con-

7 Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1 65 sidered as validly published, and the same applies to the order Convolvuletalia sepium. On the other hand, if we accept the rather detailed references given by Tüxen as sufficient (author and year, study area, original name of the association, number of relevés), then the name Senecionion fluviatilis is valid but illegitimate: The diagnoses of associations 3 and 5 refer without exception to shrub and forest communities dominated by Salix and Populus species. Tüxen s intention was to disentangle the herbaceous curtain ( Schleier-Gesellschaft ) from the woody component of alluvial shrubs, considering the published relevés as a complex of two different communities. However, the cited diagnoses (e.g. Salicetum Steffen 1931) clearly represent woody communities. Therefore, the new association names are illegitimate according to Art. 29b, and so are the names Senecionion fluviatilis and Convolvuletalia sepium. Given that the names published by Tüxen (1950) are considered as invalid, the names Convolvuletalia sepium and Senecionion fluviatilis are not validated by Moor (1958) as was supposed by Berg et al. (2004). Moor included two associations in the alliance Senecionion fluviatilis: Impatienti- Solidaginetum Moor 1958, and Cuscuto-Convolvuletum Tx The latter association is validated by Moor (1958) but Senecio fluviatilis is neither indicated in the relevés of these two associations nor in any other part of the original diagnosis. Therefore, the alliance is invalid according to Art. 3f in Moor s paper, and the order Convolvuletalia sepium includes no validly published alliance (Art. 8). No Votes (nomenclature in need of revision). (9) To mutate the name Staticetum limoniae Christiansen 1927 to Limonietum vulgaris nom. mut. prop. Proposed by J. Dengler (see Berg et al. 2004: 587). Staticetum limoniae Christiansen 1927, Föhrer Heimatbücher 16: 38. Typus: nondum selectus? This name is used for a temperate European salt marsh community dominated by Limonium vulgare Mill. ( Statice limonium L.). The genus name Statice L. (Typus: Statice armeria L.) is rejected as homotypic synonym of Armeria Willd. nom. cons. (ICBN, App. III). Therefore, the correct name of the name-giving species is Limonium vulgare. Other syntaxa names based on this species (e.g. Crithmo-Staticetea Br.-Bl. 1952) should be mutated as well. (10 11) To mutate the names Festucion maritimae Christiansen 1927 and Festucetum maritimae Christiansen 1927 to Puccinellion maritimae nom. mut. prop. and Puccinellietum maritimae nom. mut. prop. Proposed by J. Dengler (see Dengler et al. 2004: 372). Festucion maritimae Christiansen 1927, Föhrer Heimatbücher 16: 27. Typus: Festucetum maritimae Christiansen 1927 (Lectotypus Art. 20). Festucetum maritimae Christiansen 1927, l.c.: 32. Typus: Relevé on p. 32 (Holotypus). The alliance Festucion maritimae was established for coastal salt marsh communities of temperate Europe. The name-giving species is Festuca maritima (Huds.) Koch ( Puccinellia maritima (Huds.) Parl.). The name Festuca maritima (Huds.) Koch has been rejected as a later homonym of F. maritima L., therefore Art. 44 applies. The first choice of a non-homonymous taxon name for both the alliance and the association name seems to be Puccinellia maritima. Thus, the correct names of the alliance and the association are Puccinellion maritimae Christiansen 1927 nom. corr., and Puccinellietum maritimae Christiansen 1927 nom. corr., respectively. No mutation is necessary. Votes: 0 pro, 4 contra (unnecessary). (12 14) To mutate the names Sphagnetalia medii Kästner & Flößner 1933, Sphagnion medii Kästner & Flößner 1933, and Sphagnetum medii Kästner & Flößner 1933 to Sphagnetalia magellanici nom. mut. prop., Sphagnion magellanici nom. mut. prop., and Sphagnetum magellanici nom. mut. prop. Proposed by J. Dengler (see Berg et al. 2004: 587). Sphagnetalia medii Kästner & Flößner 1933, Veröff. Landesver. Sächs. Heimatschutz 4: 16. Typus: Sphagnion medii Kästner & Flößner 1933 (Holotypus). Sphagnion medii Kästner & Flößner 1933, l.c.: 16, 74. Typus: Sphagnetum medii Kästner & Flößner 1933 (Lectotypus Art. 20). Sphagnetum medii Kästner & Flößner 1933, l.c.: 81. Typus: Table 14: 1 (Lectotypus Steiner 1992: 321). The order Sphagnetalia medii includes bog communities of sub-continental regions of Europe. Sphagnum medium Limpr is a later synonym of S. magellanicum Brid However, the names Sphagnetalia medii, Sphagnion medii, and Sphagnetum medii are all illegitimate according to Art. 29b since the name-giving moss species does not belong to the highest of the dominant strata determining the structure of the vegetation. In the original diagnosis (Kästner & Flössner 1933: Table 14), tall grasses (Eriophorum vaginatum) and dwarf shrubs (Calluna vulgaris, Empetrum nigrum etc.) reach cover values > 25%. Therefore, the names published by Kästner & Flössner are not acceptable as correct names. No Votes (nomenclature in need of revision). (15) To mutate the name Hordeetum nodosi Krisch 1974 to Hordeetum secalini nom. mut. prop.

8 66 W. Willner et al. Proposed by J. Dengler (see Berg et al. 2004: 587). Hordeetum nodosi Krisch 1974, Feddes Repert. 85: 131. Typus: nondum selectus? This is another community of coastal salt marshes of temperate Europe. Krisch (l.c.) used the taxon name Hordeum nodosum L. but the nomenclatural type of this name belongs to H. bulbosum L. (Baum & Jarvis 1985: 531). The correct name of the name-giving taxon of this association is H. secalinum Schreb. Therefore, Krisch used the name Hordeum nodosum in a sense that is not in accordance with the nomenclatural type of the taxon name, and Art. 43 must be applied. Votes: 0 pro, 4 contra (unnecessary). (16) To reject the name Laricetum deciduae Bojko 1931 nom. amb. prop. Proposed by W. Willner (see Willner & Grabherr 2007: 241). Laricetum deciduae Bojko 1931: 128. Typus: Table on p. 132., col. 2 = rel. no. 17 (Lectotypus Willner & Grabherr 2007: 241). On steep, calcareous rocks in the subalpine belt of the Alps, European larch (Larix decidua Mill.) forms ± monodominant stands with a rather open canopy. Zukrigl (1973) described this community type in detail and proposed for it the provisional name Rhodothamno-Laricetum (nom. inval., Art. 3b). Wallnöfer (1993, Die Pflanzenges. Österr. III: 272) used the name Laricetum deciduae Bojko 1931 for this association. However, the original diagnosis of this name consists of two relevés which were taken mostly on non-calcareous bedrock (one relevé represents a mixture of calcareous and non-calcareous bedrock). The type-relevé chosen by Willner & Grabherr (2007) clearly represents an acidic forest community. It was assigned to the association Vaccinio-Pinetum cembrae (Pallmann & Haffter 1933) Oberd ( Larici-Pinetum cembrae Ellenberg 1963) by Karner (in Willner & Grabherr 2007: 216). Therefore, Wallnöfer used the name Laricetum deciduae in a sense that excludes its (later selected) nomenclatural type. The name Rhodothamno-Laricetum was validated by Willner & Zukrigl (1999: 154) and has to be used as correct name of the calcareous larch forests community. The re-introduction of the name Laricetum deciduae in its original sense (i.e. as the correct name of the acidic forest community Vaccinio- Pinetum cembrae) would be a source of confusion and continual errors. (17) To conserve the name Berberidion Br.-Bl. ex Tx nom. cons. propos. Proposed by W. Willner (see Willner & Grabherr 2007: 224). Berberidion Braun-Blanquet ex Tüxen 1952: 96. Typus: Pruno-Ligustretum Tüxen 1952: 101 (Lectotypus Willner & Grabherr 2007: 224). Under the name Berberidion, thermophilous shrub communities of submediterranean and temperate Europe are subsumed. The alliance was established by Braun-Blanquet (1950: 349) who included two associations in the original diagnosis: Rosetum rhamnosum nom. inval. (Art. 2b, 3e), and Coryleto-Populetum (recte: Corylo-Populetum). The latter bears a reference to the name Coryletum Beger 1922: 81. Beger (l.c.) published under this name a species list with quantitative indications for only a few species. Neither for Populus tremula nor for Berberis vulgaris, a quantitative value is given. This is certainly a borderline case of a valid diagnosis, but since both species are indicated in Beger s relevé, the names Berberidion and Corylo-Populetum seem to be validly published (see Art. 3f). The name Corylo-Populetum Br.-Bl is an illegitimate nomen superfluum and automatically typified by the earlier legitimate name of Beger (Art. 18b, see also Weber 1999: 16). Being the only valid association in the original diagnosis, the Corylo-Populetum Br.-Bl ( Coryletum Beger 1922) is the nomenclatural type of the name Berberidion Br.-Bl However, some years later, Braun-Blanquet (1961: 68) split the alliance into two: The Corylo- Populetum nom. illeg. was classified within a new alliance Corylo-Populion Br.-Bl while the Rosetum rhamnosum (under the new name Berberido-Rosetum Br.-Bl. 1961: 189) remained in the alliance Berberidion. Obviously, Braun- Blanquet regarded the Berberido-Rosetum as typical core of the Berberidion, but since this association was not validly published in 1950, it is not available as formal type of the alliance name. The alliance Corylo-Populion is accepted in several recent surveys (e.g. Rivas-Martínez et al. 1999, Willner & Grabherr 2007). According to a strict application of the Code, the name Berberidion had to be adopted for the latter alliance while the larger part of the Berberidion s.lat. would need a new name. To avoid such an inappropriate change of commonly used names, the conservation of a later publication of the name Berberidion together with a different type is proposed: The next author who used the name Berberidion was Tüxen (1952). Together with the alliances Rubion subatlanticum nom. illeg., Prunion fruticosae Tx. 1952, and Salicion arenariae nom. inval. (Art. 2b), he included the alliance Berberidion in a new order Prunetalia spinosae Tx. 52. Weber (1990: 106) selected the Berberidion as lectotypus of the order name. Willner & Grabherr (2007: 224) proposed to conserve the name Berberidion Br.-Bl. ex Tx with the simultaneously published association Pruno-Ligustretum Tx as lectotypus. This association is the central association of the alliance (in the sense of Dierschke 1988) and has been unanimously included in the alliance Berberidion since its first publication in 1952.

9 Report of the Committee for Nomina Conservanda, Ambigua, Inversa and Mutata: 1 67 (18) To conserve the name Asperulo-Fagetum Sougnez & Thill 1959 against Dentario bulbiferae-fagetum Hartmann 1953 and Festuco altissimae-fagetum Schlüter 1957, and to mutate it to Galio odorati-fagetum nom. cons. et mut. propos. Proposed by W. Willner (see Willner & Grabherr 2007: 233). Asperulo-Fagetum Sougnez & Thill 1959: 36. Typus: Sougnez & Thill 1959: 37, Rel. 42a. (Lectotypus Dierschke 1989: 134). The beech forest community on loamy, often moderately acidic soils of Central Europe is known as Asperulo-Fagetum or Galio odorati-fagetum (Dierschke 1989, Müller in Oberdorfer 1992, Willner 2002). The first author who distinguished this forest type as separate association seems to be Hartmann (1953). He divided the Fagetum boreoatlanticum Tüxen 1937 nom. illeg. into three associations: (1) Luzulo-Fagetum nom. illeg. (later homonym of Luzulo-Fagetum Meusel 1937): species poor, acidic beech forests; (2) Dentario bulbiferae-fagetum: species rich, moderately acidic beech forests; and (3) Lathyro verni- Fagetum nom. inval. (Art. 3b): basiphilous beech forests. Hartmann distinguished five subassociations within the new association Dentario bulbiferae-fagetum. One of them was named as typical subassociation. According to Art. 19, the nomenclatural type of the association name must be chosen from this subassociation. Among others, Hartmann cited the following sources in the protologue of the typical subassociation (Hartmann l.c., appendix p. VI): Fagetum boreoatlanticum dryopteridetosum linnaeanae Tüxen 1937, Fagetum cardaminetosum bulbiferae Büker Since Tüxen (1937) only published a synoptic table, a relevé from Büker (l.c.) is chosen as lectotypus for the association name (see below). A few years later, Schlüter (in Grüneberg & Schlüter 1957: 894) described the association Festuco altissimae-fagetum, giving the name Fagetum boreoatlanticum festucetosum sylvaticae Tx in the synonymy. However, in the following years only the association Luzulo- Fagetum was generally accepted while for the rest of the old Fagetum boreoatlanticum, the name Melico-Fagetum became commonly used (see below). In a revision of the beech forest communities of southern and north-western Germany, Müller (1989) and Dierschke (1989) adopted the name Asperulo-Fagetum Sougnez & Thill 1959 (in the mutated form Galio odorati-fagetum) for the community on moderately acidic soils, and this name has been commonly used for the last two decades (e.g. Müller in Oberdorfer 1992, Mucina et al. 1993, Willner & Grabherr 2007). The re-introduction of the earliest valid name for this community, i.e. Dentario bulbiferae-fagetum Hartmann 1953, would clearly contradict the intention of the Code to promote stability. Therefore, it was proposed to conserve the name Asperulo-Fagetum Sougnez & Thill 1959 against the earlier synonyms Dentario bulbiferae-fagetum Hartmann 1953 and Festuco altissimae-fagetum Schlüter 1957, and at the same time to adapt the name to the contemporary taxonomic literature by mutating it to Galio odorati-fagetum. The name Asperula odorata L. is no longer in use since the species has been treated as Galium odoratum (L.) Scop. in all floras of Europe for more than 20 years. The name Melico-Fagetum is not threatening the proposed nomen conservandum as will be shown in the following. The idea of Melico-Fagetum was already introduced in Tüxen (1954) where he split his Fagetum boreoatlanticum into two associations. For the acidophilous beech forests (Fagetum boreoatlanticum luzuletosum Tx. 1937), he accepted the name Luzulo-Fagetum Meusel However, for the remaining part of the Fagetum boreoatlanticum, he used the invalid name Melica-Buchenwald. In a footnote on p. 467, he remarked: Due to the raising of Luzulo-Fagetum to the rank of a separate association, a new name for the species-rich beech forests is necessary. However, in order to prevent a prejudgement of ongoing works, we used the provisional name Melica-Buchenwald (translated from German). In the same year, Seibert (1954) used the name Melico-Fagetum for a single relevé, but since he suggested this name as being provisional, this was not a valid publication (Art. 3b). Tüxen (1955) published a list of the plant communities of north-western Germany, giving the synonyms of his survey from 1937 in brackets (see Tüxen l.c.: 162). Three beech forest communities are listed in the paper: (1) Luzulo-Fagetum [without author citation] (Fagetum boreoatlanticum luzuletosum) ; (2) Melico-Fagetum Lohm. apud Seibert 1954 (Fagetum boreoatlanticum p.p.) ; and (3) Cariceto-Fagetum [without author citation and without synonym]. The last name refers to the association Carici-Fagetum Moor 1952 which had been reported from north-western Germany by Lohmeyer (1953). No synonym is given for this community because it had not been recognized in The name Melico-Fagetum is clearly a substitute for the name Fagetum boreoatlanticum Tx (excluding the subassociation luzuletosum). Curiously, Tüxen attributed the name to Lohmeyer apud Seibert Seibert mentioned the name Melico-Fagetum in several publications in 1954 (without describing it validly), but in none of them the name was attributed to Lohmeyer. Therefore, Tüxen s diagnosis is rather a nomen novum (Art. 39) for his own name Fagetum boreoatlanticum than a validation of Seibert s provisional description of 1954, and the correct author citation should be Melico-Fagetum Tüxen (1937) The nomenclatural type of the replaced name is chosen from the subassocation Fagetum boreoatlanticum elymetosum Tx which, according to recent

10 68 W. Willner et al. syntaxonomical schemes, belongs to the basiphilous association Mercuriali-Fagetum Scamoni 1935 (= Hordelymo-Fagetum Kuhn 1937 = Lathyro-Fagetum Hartmann ex Müller 1966). The single relevé published by Seibert (1954) belongs to the same association. The acceptance of this proposal would not preclude authors from adopting the names Dentario bulbiferae-fagetum Hartmann 1953 and Festuco altissimae-fagetum Schlüter 1957 as correct names of beech forest communities if they consider them as belonging to associations different from Galio odorati-fagetum. Typifications: Fagetum boreoatlanticum Tüxen 1937: 139. Neotypus Willner hoc loco: Diemont 1938, Tab. 2: 11, Ith NW Lauenstein, Kreis Holzminden. Fagetum boreoatlanticum elymetosum Tüxen 1937: 140. Neotypus Willner hoc loco: Typus of the association. Dentario bulbiferae-fagetum Hartmann 1953: 160 & app. VI. Lectotypus Willner hoc loco: Büker 1942, Tab. 21: 4. Melico-Fagetum Tüxen (1937) 1955: 176 Fagetum boreoatlanticum Tüxen (19) To conserve the name Andromedo tetragonae-hylocomietum [proliferi] Fries 1913, and to mutate and invert it to Hylocomio splendentis- Cassiopetum tetragonae nom. cons., mut. et invers. propos. Proposed by B. Sieg, B. Drees & F. J. A. Daniёls (see Sieg et al. 2006: 16). Andromeda tetragona-hylocomium-ass. Fries 1913: 90. Typus: Fries 1913, single relevé p. 90/91 (Holotypus). The association comprises dwarf shrub heathlands on acidic soil dominated by Cassiope tetragona. It occurs in the alpine belt of boreal areas, but it is mainly distributed in the northern Low-Arctic and southern High-Arctic. It is usually assigned to the alliance Phyllodoco-Vaccinion Nordhagen 1936 within the class Loiseleurio-Vaccinietea Eggler According to Principle II of the Code, association names of the Uppsala School published before are not subject to the regulations of the Code, as they correspond in reality to sociations, but may be proposed as nomina conservanda. However, it is somewhat ambiguous whether the association names of Fries (1913) are to be treated as names of the Uppsala School in the sense of Principle II or not. In the first years after the starting point (1910) of the Code, differences between the Zürich-Montpellier-School and the Uppsala School are, if visible at all, not obvious and not substancial (see, e.g., Fries 1913: for remarks on his methods and his reference to the association concept of the Botanical Congress in Bruxelles 1910). The Committee concludes that, all other requirements fulfilled, names which do not unambiguously belong to the Uppsala School should be treated as validly published. Therefore, a conservation according to Art. 52 is not necessary in this case. Andromeda tetragona L. is now treated as Cassiope tetragona (L.) D. Don (Tutin et al. 1972). The name Hylocomium proliferum (L.) Lindb., which is the only Hylocomium species in the original diagnosis, is rejected as nom. illeg., and the correct name of the species is Hylocomium splendens (Hedw.) Schimp. Since the dwarf shrub Cassiope tetragona belongs to the highest stratum determining the structure, the name must be inverted according to Art. 42. Note: Fries (1913: footnote on p. 49/50) used two different denomination concepts for his associations, one with German words within the names and, as synonyms, one in accordance with the terminology of Kerner (1863). For the latter ones he often used association names derived from scientific plant names in accordance with the Code. These synomyms in the sense of Fries (1913: 50) are not synonyms in the sense of Def. X of the Code, because a synonym can only occur in connection with a given validly published name. However, the association names containing German words are invalidly published according to Art. 2c and to be treated as not published at all according to Def. IV. Therefore, the association names of Fries formed from scientific plant names are no synomyms in the sense of Art. 3a, but the only validly published names for the associations according to Art. 3c Note and Expl. 2. The occurrence of Calamagrostis lapponica in a higher stratum (10 30 cm, Fries 1913: 49) than the other vascular plants (3 10 cm) does not make the association name illegitimate according to Art. 29b because Calamagrostis is very scattered (cover degree only 1, vereinzelt ) and far from forming a dominant stratum (> 25%, see Art. 29b). Votes: 4 pro, 0 contra (mutation and inversion recommended, conservation unnecessary). Concluding remarks To accelerate the decision process of the Nomenclature Commission concerning nomina ambigua, nomina mutata and nomina conservanda, authors should submit their proposals in electronical form to the first author of this report. It is not necessary to send any supporting documents (e.g. the original diagnosis of a name) unless being asked for. The members of the Committee will screen the proposals and may contact the authors if further information is required. Please consider the proposals included in this report as guideline on how a proposal should look like. After discussion of the Committee, proposals will be published in future reports together with a recommendation whether they should be accepted or not. The final decision will be made by the Nomenclature Commission. However, we consider it crucial for the general acceptance of nomina ambigua, nomina mutata and nomina conservanda that all scientists