Why Charadrius got renamed to Anarhynchus
by Oscar G. Miranda
You might have noticed that this year some of the species that were part of the Charadrius genus, were changed to the Anarhynchus genus.
A Snowy Plover (Anarhynchus nivosus, formerly Charadrius nivosus) incubating its chick. Photo by Medardo Cruz López.
Recently I asked David Donsker, the Managing Editor of International Ornithological Committee (IOC) World Bird List, for an explanation.
“Wisdom begins with putting the right name on a thing.”
He said that they used the most recent phylogeny of Černý & Natale 2022 as the primary basis for their taxonomy of shorebirds on the latest edition of the IOC list, because it was the most speciose and most detailed.
Time-calibrated phylogeny of 353 species of shorebirds based on the penalized-likelihood rate-smoothing analysis of a total-evidence phylogram inferred using RAxML-NG from 27 genes and 69 morphological characters. Nodes with bootstrap support ⩾70% are indicated by circles; nodes with bootstrap support <70% are indicated by squares. Fossil-calibrated nodes are shown in black. Blue bars denote 95% confidence intervals based on 1000 bootstrap pseudoreplicates. Shaded tabs represent higher-level clades; background shading indicates geochronological epochs. Ma = million years ago; Ster. = Stercorariidae; Glareol. = Glareolidae; Tur. = Turnicidae; Jac. = Jacanidae; Haem. = Haematopodidae; Rec. = Recurvirostridae; Bur. = Burhinidae; Chion. = Chionida; LC = Late Cretaceous; Pal = Paleocene; Eo = Eocene; Ol = Oligocene; Mio = Miocene; Pli = Pliocene; Ple = Pleistocene. Representative species are illustrated next to their lineages. Taken from Černý & Natale 2022.
In the phylogeny you could see that the formerly CRD II of Charadrius plovers described in Dos Remedios et al. (2015), is the one that now is considered by the IOC World Bird List as Anarhynchus.
(a) Biogeographic regions used to define current breeding distributions for each species. (b) The maximum clade credibility tree for 29 Charadrius and five species currently assigned to different genera. Results of parsimony ancestral area analysis are shown for all nodes (pie chart colours by region) and Bayesian binary Markov chain Monte Carlo (BBM) results with probability distributions are added for the three basal Charadrius nodes (larger pie charts). Minor clades within CRD I and CRD II are labelled a–f. Posterior probabilities are indicated at each node. Taken from Dos Remedios et al. (2015).
This is because the Wrybill, Anarhynchus frontalis, is deeply imbedded in that clade. And given that Anarhynchus Quoy & Gaimard, 1832 has precedence over Ochthodromus Reichenbach 1852, they chose to name this clade Anarhynchus.
A wrybill (Anarhynchus frontalis) protecting its chick. Photo taken by Jonathan Harrod.
Further, he said that since the divergences between Anarhynchus, Ochthodromus, and Eupoda in the Černý & Natale 2022 phylogeny were shallow, they chose to keep these species congeneric.
