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Formal nomenclatural proposals of this kind rest on a set of rules that most readers outside vegetation science may never have encountered. The International Code of Phytosociological Nomenclature, currently in its fourth edition, functions much like the botanical code that governs plant species names, but it applies to vegetation units rather than organisms. An association such as Diantho deltoidis-Armerietum elongatae is not a species but a recurring combination of species that ecologists have judged to form a characteristic community type. Because these units are defined by human interpretation of field data rather than by evolutionary lineage, their names are especially vulnerable to duplication, misapplication, and shifting circumscriptions. The Code therefore provides mechanisms, including typification and formal conservation, that allow the community of researchers to stabilize names that have become widely used even when older competing names exist on purely chronological grounds.

The concept of a nomenclatural type is central to this system. Just as a species name is anchored to a preserved specimen, a syntaxon name is anchored to a type relevé, a vegetation plot recorded in a specific location at a specific time. When the original author failed to designate a type, or when the original material is ambiguous, later researchers may designate a lectotype from among the original records or a neotype from new material that best matches the original description. The present proposals illustrate both processes. The lectotype of Diantho deltoidis-Armerietum elongatae was selected from a table published by Pötsch in 1962, while neotypes were designated for the two older competing names. These typifications are not bureaucratic formalities; they determine which real-world vegetation the name must apply to, and thus whether a name can coexist with or must yield to another.

The case of Diantho deltoidis-Armerietum elongatae demonstrates why strict priority alone can be a poor guide to nomenclatural practice. The association describes meso-xeric sand grasslands dominated by Festuca trachyphylla and characterized by Dianthus deltoides and Armeria elongata, communities that flourish on acidic, nutrient-poor sands across the North European Plain. The name has been applied consistently by dozens of authors across Germany, Poland, the Baltic states, and southern Scandinavia over more than six decades. Its two older rivals, by contrast, have had minimal uptake. Armerio elongatae-Rumicetum tenuifolii, described from southern Sweden in 1951, has been essentially ignored in the literature. Armerio-Festucetum, described from Franconia in 1960, fared somewhat better but was often applied in a broad sense that swallowed a second, clearly distinct association, and in the Polish lowlands, which form the heart of the association’s range, it was apparently never used at all. Under such circumstances, displacing the established name in favor of obscure predecessors would create far more confusion than it resolves.

The phantom name problem adds another layer of complexity. Several respected floristic works attribute the association to Krausch in 1959, yet a careful examination of Krausch’s publications from that year shows that he used a different name, Diantho deltoidis-Festucetum, and that this name was ineffectively or invalidly published in both instances. A phantom name of this kind, repeated from citation to citation without ever having been validly established, illustrates how errors propagate through the literature and why the Code requires verification against original sources rather than reliance on secondary attributions. Correcting such misattributions is a service to future researchers, since a name with a false authority cannot be reliably traced to its nomenclatural basis.

The proposal to reject Festuco ovinae-Thymetum angustifolii as a nomen dubium turns on a problem that is common in older phytosociological literature: the coarse species concepts of earlier decades. Tüxen’s 1937 description relied on Festuca ovina in a broad sense, a taxonomic aggregate that modern research has split into several distinct species, including F. ovina in the strict sense, F. guestfalica, F. lemanii, and F. stricta subsp. trachyphylla. In the dry grasslands of northwestern Germany, these taxa occupy different niches and characterize different communities, so the identity of the matrix grass fundamentally determines the syntaxonomic placement of the stands Tüxen described. Because the protologue cannot be unambiguously assigned to any one of these taxa, and because a later neotypification failed to resolve the ambiguity, the name cannot be applied with confidence. The additional finding that some authors have used the name for communities dominated by Festuca filiformis, a species Tüxen explicitly differentiated elsewhere, renders the name ambiguous as well, since such usage excludes the type and violates the Code’s provisions on unambiguous application.

The third proposal concerns a name so obscure that rejecting it may seem unnecessary, yet the logic is preventive rather than remedial. Corynephoro canescentis-Caricetum arenariae was described in 1928 from a single vegetation plot, which by the rules of the Code constitutes its holotype. In that plot, the bryophytes and lichens, which often carry more diagnostic weight than the vascular plants in these pioneer communities, were not identified. This matters because the two associations that could plausibly correspond to the name, the Cetrario aculeatae-Corynephoretum canescentis and the Caricetum arenariae, occur side by side on the same dune sands and share the two most conspicuous vascular species, Corynephorus canescens and Carex arenaria. They are separated chiefly by their cryptogam floras, with the former hosting a rich assemblage of lichens such as Cladonia species and the latter differing in its bryophyte composition. Without the cryptogam data, the holotype cannot be assigned to either association, and the name therefore floats without secure meaning. Rejecting it now, while it remains unused, prevents a future researcher from resurrecting it and destabilizing two well-established associations at once.

The ecological context of these decisions deserves emphasis. The class Koelerio-Corynephoretea comprises the dry, sandy grasslands of temperate Europe, habitats that are among the most species-rich and most threatened in the region. Many of their characteristic plants are specialists of nutrient-poor, acidic sands, relics of a landscape history that includes both natural disturbance and centuries of pastoral land use. As agriculture intensified and nitrogen deposition increased, these communities retreated to remnants, making their consistent documentation and classification a matter of practical conservation concern, not merely academic taxonomy. Cross-border vegetation maps, habitat assessments, and red-list evaluations all depend on names that mean the same thing in Germany, Poland, Latvia, and Sweden. A single ambiguous name can fragment datasets and obscure genuine ecological patterns.

The governance mechanism behind these proposals is also worth noting. The Committee for Change and Conservation of Names operates under the Group of Phytosociological Nomenclature, an international body that evaluates formal applications and issues binding decisions. This mirrors the committees that handle conserved and rejected names under the botanical and zoological codes, and it ensures that nomenclatural stability is achieved through community consensus rather than unilateral decree. The authors of the present proposals note that similar suggestions have circulated informally in the literature for years, appearing in regional overviews and revisionary papers, but that only a formal application can produce a binding outcome. This gap between informal recommendation and formal decision is a recurring feature of nomenclatural practice, and it explains why long-standing usage patterns sometimes require decades to receive official sanction.

The interplay between taxonomy and nomenclature is particularly visible in the Festuca case. Nomenclatural problems are often blamed on careless early authors, but here the root cause is taxonomic progress: the splitting of a once-broad species into several narrower ones created ambiguities that Tüxen could not have anticipated. Similar situations arise whenever modern molecular or morphological research revises species limits within groups that earlier vegetation ecologists recorded at aggregate level. The Code’s provisions on nomina dubia exist precisely for such cases, allowing names whose application cannot be determined to be set aside rather than forcing researchers into arbitrary typifications that may misrepresent the original concept. The alternative, conserving the younger name against the dubious older one, is offered as a fallback, showing that the authors have considered the committee’s possible responses and provided a coherent path in either direction.

Finally, the distinction between valid and effective publication underlies the entire discussion. The Code requires that names be effectively published, validly described, and accompanied by an adequate type or diagnostic material. The failed conservation of the widely used but invalid Spergulo morisonii-Corynephoretum canescentis illustrates that popularity cannot substitute for validity; only names that meet the formal requirements can be conserved, and a name that was never validly published in the first place is beyond the committee’s reach. For researchers compiling regional vegetation classifications, these cases serve as a reminder that every name in a syntaxonomic list carries a chain of nomenclatural decisions behind it, and that the health of the classification depends on the careful, sometimes painstaking, work of tracing those chains to their sources.

Subject of Research: Nomenclatural proposals for sand grassland plant community names in the class Koelerio-Corynephoretea

Article Title: Proposals (45–47) to conserve the name Diantho deltoidis-Armerietum elongatae Krausch ex Pötsch 1962 as a nomen conservandum and to reject two nomina dubia in the class Koelerio-Corynephoretea

Article References: Proposals (45–47) to conserve the name Diantho deltoidis-Armerietum elongatae Krausch ex Pötsch 1962 as a nomen conservandum and to reject two nomina dubia in the class Koelerio-Corynephoretea. (n.d.). https://doi.org/10.3897/VCS.177197

Image Credits: AI Generated

DOI: 10.3897/VCS.177197

Keywords: phytosociology, nomenclature, Koelerio-Corynephoretea, sand grasslands, Diantho deltoidis-Armerietum elongatae, nomen conservandum, nomen dubium, ICPN, vegetation classification, Corynephorus canescens, Armerion elongatae, Europe