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Parrots (Order: Psittaciformes) are a diverse clade that is easily distinguishable from other birds. Despite the clear characters that define Psittaciformes (hooked bills, zygodactylous feet, and plumage that is often predominantly green or red), relative morphological uniformity among parrots has made taxonomic classification a fraught endeavor for over a century. Parrot systematics were propelled forward when DNA sequencing data shed insights into higher- and species-level relationships. However, despite these significant advances, major gaps in taxon sampling and uncertainty in relationships remained due to inferring phylogenetic relationships with short fragments of DNA. Recent work using genome-wide molecular markers with nearly complete parrot species-level sampling has brought clarity to many of the remaining outstanding questions on taxonomic relationships. Here, we build on this work by including four additional species to present a taxonomic revision of Psittaciformes better aligned with its evolutionary tree. We infer maximum likelihood and time-calibrated phylogenies for parrots, present accounts for 106 genera, compare how our findings relate to previous work, and highlight future areas of research. The family-group nomenclature we propose reflects deep evolutionary divergences with diagnosable synapomorphies that are commensurate across comparable ranks in psittaciform clades. We erect three new family-group names at the rank of tribe (Brotogerini Smith, Thom, and Joseph, 2024; Neophemini Schodde, Mason, Smith, Thom, and Joseph, 2024; Bolbopsittacini Smith, Thom, and Joseph, 2024). We elevate one tribe to subfamily rank for the cacatuid genus Probosciger and we restrict usage of the recently introduced tribe Touitini to its type genus Touit. At shallower taxonomic scales, recognition of more rather than fewer genera addresses issues of paraphyly or high discordance in morphological and genomic characters at those levels. We support many reinstatements of older generic names advocated in recent decades, and we further reinstate five valid, available generic names not widely used in recent literature if at all (Licmetis, Gymnopsittacus, Clarkona, Suavipsitta, Cardeos). We advocate the retention of Vini Lesson, 1833, over Coriphilus Wagler, 1832, based on preliminary examination showing substantially more frequent usage of the former. We redraw generic limits in some other cases (e.g., Bolborhynchus parrotlets and allies) and this includes recognizing fewer genera than recently proposed for the Psittacula sensu lato ringneck parakeets. Our revised classification of parrots addresses many longstanding taxonomic questions including those that have arisen through the acquisition of genetic data. It provides context for the temporal origins of psittaciform clades and the taxonomic and phenotypic diversification throughout their evolutionary history. We hope that it will be a benchmark guiding further taxonomic study as well as for downstream analyses in many other fields. [ABSTRACT FROM AUTHOR]

Museum collections of birds are a key source of data on the colours of 'soft parts', e.g. legs, feet, bill (maxilla, mandible), wattles, periocular skin and, our focus here, the iris of the eye. However, subjective descriptions of soft parts' colours have long plagued their use, whether in research or in illustrations of birds. We document a case where reasonable doubt about the accuracy of iris colour recorded more than 50 years ago in several taxonomically important series of specimens of the Australian Spinifex Pigeon Geophaps plumifera is probably unresolvable. This doubt clouds the downstream use of the specimens in a complete understanding of geographical and temporal variation, and taxonomy. We discuss how ornithologists may apply methods now readily available that will enable more rigorous recording of soft parts' colours, despite many valid limitations. This especially applies in situations where existing knowledge dictates care, such as in already known zones of taxonomic intergradation or when colours known to be unusual and unexpected are seen. [ABSTRACT FROM AUTHOR]

The Splendid Fairywren Malurus splendens has four distinct phenotypic forms currently recognised as subspecies, although three species have been recognised within the group in the past. Here, we use multilocus nuclear DNA to test the recent hypothesis that the Splendid Fairywren represents three allopatric taxa with little to no modern-day contact, despite phenotypic evidence of periods of past contact and gene flow. Our nuclear dataset is concordant with earlier mtDNA-based data in supporting three distinct genetic groups within M. splendens. These genetic groups align with the three phenotypically distinct forms recently hypothesised to be allopatric and previously described at species-level – western M. splendens, central M. callainus and eastern M. melanotus. Nuclear gene flow does not appear to be rampant between the three forms; however, several individuals show signals of admixed nuclear ancestry, which we cannot distinguish as having resulted from incomplete lineage sorting, poor phylogenetic signal, or gene flow. Given changing modern taxonomic interpretations of the significance of gene flow in speciation, we argue that recognising three distinct species within the M. splendens complex might better represent their evolutionary distinctiveness, rather than continuing to treat these genetically and morphologically distinct forms as subspecies of a widespread polytypic species. Our study highlights the interesting complexity of determining species status when taxa are in the ‘grey zone’ near the subspecies/species continuum, and the value gained from adding perspectives from nuclear DNA. [ABSTRACT FROM AUTHOR]