Conversion of the names Pyxicephaloidea, Pyxicephalidae and Pyxicephalinae (Anura, Ranoidea) into phylogenetic nomenclature

The recent publications of the sixth edition of the PhyloCode and of the monograph Phylonyms now allow the publication of nomenclatural acts that will establish priority under that code. This includes defining existing and newly proposed taxon names in conformity with the PhyloCode. Among amphibian taxa, very few names have been converted so far, and we take the opportunity of our recent phylogenetic analysis of neobatrachians focusing on an extinct genus of Pyxicephalidae, Thaumastosaurus, from the Eocene of Western Europe, to convert the names Pyxicephaloidea, Pyxicephalidae and Pyxicephalinae into phylogenetic nomenclature, following the PhyloCode rules.

The phylogenetic nomenclature of ornithischian dinosaurs

Ornithischians form a large clade of globally distributed Mesozoic dinosaurs, and represent one of their three major radiations. Throughout their evolutionary history, exceeding 134 million years, ornithischians evolved considerable morphological disparity, expressed especially through the cranial and osteodermal features of their most distinguishable representatives. The nearly two-century-long research history on ornithischians has resulted in the recognition of numerous diverse lineages, many of which have been named. Following the formative publications establishing the theoretical foundation of phylogenetic nomenclature throughout the 1980s and 1990s, many of the proposed names of ornithischian clades were provided with phylogenetic definitions. Some of these definitions have proven useful and have not been changed, beyond the way they were formulated, since their introduction. Some names, however, have multiple definitions, making their application ambiguous. Recent implementation of the International Code of Phylogenetic Nomenclature (ICPN, or PhyloCode) offers the opportunity to explore the utility of previously proposed definitions of established taxon names. Since the Articles of the ICPN are not to be applied retroactively, all phylogenetic definitions published prior to its implementation remain informal (and ineffective) in the light of the Code. Here, we revise the nomenclature of ornithischian dinosaur clades; we revisit 76 preexisting ornithischian clade names, review their recent and historical use, and formally establish their phylogenetic definitions. Additionally, we introduce five new clade names: two for robustly supported clades of later-diverging hadrosaurids and ceratopsians, one uniting heterodontosaurids and genasaurs, and two for clades of nodosaurids. Our study marks a key step towards a formal phylogenetic nomenclature of ornithischian dinosaurs.

Registration of Neostromboidae Clades in the RegNum of the PhyloCode, and Errata

This paper provides the International Code of Phylogenetic Nomenclature RegNum repository registration numbers for the clades defined in The Festivus. The definitions are based on the current understanding of the internal resolution within Stromboidae, and maybe amended as further taxa are resolved. This set of registration references reflects the refined definitions that have become necessary with the activation of the PhyloCode (2020) and the RegNum protocols. The use of types is not a requirement of the PhyloCode, but there use herein does resolve much of the differences between the IZCN and PhyloCode in practice. Errata for Maxwell and Rymer (2021) are noted at the end.

Resolving phylogenetic and classical nomenclature: A Revision of Canarium Schumacher, 1817 (Mollusca, Neostromboidae, Strombidae)

This revision of the genus Canarium Schumacher, 1817 after Abbott (1960) advances our understanding of the phylogeny of Strombidae. Morphological characters were used to generate a phylogeny using maximum likelihood and including all of the recognised species. This resulted in the recognition of one tree, and within that tree the existing genera Canarium Schumacher, 1817 Tridentarius Kronenberg & Vermeij, 2002 and Terestrombus Kronenberg & Vermeij, 2002, and two more Maculastrombus n. gen. and Neostrombus n. gen. were recognisable clades. Furthermore, within the genus Canarium, four subgenera, Canarium (Canarium), Canarium (Conundrum), Canarium (Elegantum), and Canarium (Stereostrombus), were identified and described. We describe and define taxa that are compatible with the requirements of the International Code of Phylogenetic Nomenclature (PhyloCode 2020), and also conform to the requirements of the International Code of Zoological Nomenclature (ICZN 1999). This revision assists in generating a system of nomenclature that reflects the hypothetical relationships, and is at the same time practical in its application. We designate type localities and types for included species that were not yet addressed up until now.

Are the ICZN and PhyloCode that incompatible? A summary of the shifts in Stromboidean taxonomy and the definition of two new subfamilies in Stromboidae (Mollusca, Neostromboidae)

The taxonomy of Stromboideans has, historically, been simplistic. However, recent revisions have seen new taxa introduced to distinguish relationships between species clusters. We discuss these numerous advancements in Stromboidean systematics, and describe two new subfamilies here. The key diagnostic characteristic, the basal peg on the first lateral tooth, splits the Strombidae into two clades similar to those observed with molecular data. In defining the new subfamilies, Neoaligerinae and Neostrombinae, we demonstrate that the practical application of the International Code of Phylogenetic Nomenclature (PhyloCode 2020), can also conform to the requirements of the International Code of Zoological Nomenclature (ICZN 1999). This revision further advances and strengthens the framework of Stromboidean nomenclature such that it is able to reflect the current understanding of the evolutionary relationships between members of the Stromboidea.

Towards a new classification of tribe Stachydeae (Lamiaceae): naming clades using molecular evidence

Stachydeae, comprising c. 470 species, are one of the most diverse and taxonomically puzzling groups in Lamioideae. In the present study, the phylogenetic relationships in the Eurystachys clade (a phylogenetic name for all genera attributed to Stachydeae except Melittis) were reconstructed utilizing nuclear ribosomal DNA sequences (nrETS, 5S-NTS) from 148 accessions in 12 genera. Our phylogenetic results recovered Stachys as paraphyletic with numerous traditionally recognized genera nested in it. A broadly defined Eurystachys clade, however, was monophyletic. Unlike previous studies, the present study was able to resolve the group into 12 well-supported clades, named here as (1) Eriostomum, (2) Stachys, (3) Prasium, (4) Setifolia, (5) Distantes, (6) Burgsdorfia, (7) Hesiodia, (8) Empedoclia, (9) Sideritis, (10) Marrubiastrum, (11) Swainsoniana and (12) Olisia. These 12 clades were formally named in a phylogenetic nomenclature for the Eurystachys clade. Several infrageneric units were retrieved as monophyletic, namely Sideritis sections Burgsdorfia, Empedoclia and Hesiodia, Sideritis subgenus Marrubiastrum and Stachys sections Eriostomum (including Stachys section Mucronata) and Setifolia. The findings of this study also provide the basis for a future formal classification, with two options: (1) splitting of the Eurystachys clade into 12 monophyletic genera, all of them based on pre-existing genus names and redefined to encompass additional taxa, but without clear morphological apomorphies; or (2) lumping of all segregates into a broadly defined Stachys, including widely recognized and well-defined segregates such as Prasium and Sideritis.

Less is more stable: arguing for few names in turtle’s taxonomy

Background. Beyond the International Codes of Zoological (ICZN) and Botanical Nomenclature and the PhyloCode, there is an alternative taxonomic system for phylogenetic systematics proposed. This phylogenetic nomenclature suggests the elimination of suprageneric names and the use of negative indexes instead of it. This system of nomenclature has a basic principle to identify clades: the presence of nominal heterobathmy, which is analogous to Hennig's "heterobathmy of characters", but applied to taxa names. Here I argue for an extensive use of heterobathmy as basic criteria to determinate “good” nodes to identify higher level taxa names. Methods. I used a previews published dataset (doi:10.5061/dryad.f2h6r) and ran several searches for Most Parsimonious Trees (MPT) using different search algorithms and assumptions in TNT. After that, I compared the results of different searches, mapped the characters transformations, and calculate the Bremer supports. The results were then compared with the current taxonomy proposed for Pelomedusoides, with emphasis on Bothremydidae. Results. The remarkable divergences with the current taxonomy of Bothremydidae are: (1) Kurmademydini and Bothremydini need to be redefined; (2) Cearachelyini and Galianemys lack diagnostic characters and, therefore, are not monophyletic; and (3) Bothremydidae do not possess common diagnostic characters in all MPT, thus, lacks a well supported heterobathmy with its sister-group, Podocnemidinura (=Pan-Podocnemididae). Moreover, the Infrafamily Bothremydodda has Bremer support of 3. However, given that all bothremydids are extinct, it is impossible to define a panstem clade based on a crown group. The result is an unstable nomenclature with more names than necessary. Discussion. The use of heterobathmy is a center point in Hennig's argumentation for phylogenetic reconstruction. Indeed, it implies the zero length collapsing rule applied to cladistic reconstruction (which is the TNT default option). Nonetheless, ambiguous characters or several equal MPT can imply on phylogenetic reconstructions that lack a consistent heterobathmy (i.e.: a common diagnostic character in the ancestor eidophoront of a given node in all MPT; as is the case of Bothremydidae). A possible solution is to use the suffix “formes” to designate extinct lineages with stem-species when some nodes are not well supported in a given phylogeny. In the example presented here, it would consist on naming ICZN’s Bothremydodda as “Bothremydidae” (sensu stricto) and ICZN’s Bothremydidae (sensu lato, i.e.: including stem-Bothremydidae) as “Bothremydidiformes” and avoid naming each node of the consensus tree unless it has high Bremer support. By taking into account this delimitation criterion, we can propose a more stable and clean taxonomy.