Pyrrhura

Smith, Brian Tilston, Thom, Gregory & Joseph, Leo, 2024, Revised Evolutionary And Taxonomic Synthesis For Parrots (Order: Psittaciformes) Guided By Phylogenomic Analysis, Bulletin of the American Museum of Natural History 2024 (468), pp. 1-87 : 39-40

Pyrrhura

Pyrrhura are small parakeets easily recognizable by the combination of maroon upper tails, often but not always scalloped or mottled chest plumage, and similarly often differentiated ear coverts and crown and shoulder markings on the wing.

Similar to Amazona , Pyrrhura is among the most speciose genera of Neotropical parrots. We estimate that its species diversity arose via rapid radiation within 7.1 Mya (2.2–10.6; fig. 9). Relationships within Pyrrhura , however, are among the most poorly resolved across the entire parrot phylogeny. This is due to Pyrrhura ’s rapid radiation, the use of degraded DNA from museum skins for several species and, potentially, extensive introgression and incomplete lineage sorting (see Ribas et al., 2006; Somenzari and Silveira, 2015; Urantowka et al., 2016). Although the most stringently filtered concatenated and species trees yielded a moderately well-resolved topology, there was high discordance in species-level relationships of the trees. Despite most recognized species having been sampled except P. pfrimeri , more phylogenetic work is still needed to resolve finer-scale relationships and species limits within the genus.

Our phylogenomic tree (fig. 9) is concordant with the membership of the three main evolutionary lineages identified by Joseph (2000, 2002) and Ribas et al. (2006), but some species-level relationships within these clades vary among phylogenies. Clade 1 comprises only P. cruentata of the Atlantic Forest, Brazil. Clade 2 is the picta-leucotis complex and clade 3 comprises the remaining species. Forshaw and Knight (2010) described three major groups: species with (1) barring on breast; (2) scalloping on breasts; and (3) neither breast barring nor scalloping. These three groups are not monophyletic in the phylogenomic tree, although some phylogenetic signal is apparent in these traits. Clade 1 ( P. cruentata ) has neither breast barring or scalloping. The difference has been illustrated in Joseph (2000, 2002: see figs. 2, 3 in both papers). Clade 2, which was sister to P. cruentata (fig. 9), includes representatives with breast barring or scalloping. For example, clade 2 taxa include P. leucotis and P. griseipectus of eastern Brazil, which have breast barring, and P. picta and P. amazonum that have scalloping. Clade 3 also contains the majority of Forshaw and Knight’s third group, species without barring or scalloping on breast. The remaining species, without barring or scalloping, do not form a monophyletic group within clade 3. Clade 3 also contains P. rupicola of western Amazonia, whose plumage Forshaw and Knight described as a special case of scalloping on the breast, and several species with barring (e.g., P. frontalis ; P. devillei ). Despite the presence of some phylogenetic signal in barring, scalloping, or the absence of either, the phylogeny shows this trait should not be used to define taxonomic groups.

Further genomic work to clarify relationships and species limits within Pyrrhura ideally would use fresh, wild-collected material of all taxa, many of which remain unsampled. A focus of such effort should be thorough population-level sampling across the geographical ranges of all nominal species but especially for the taxonomically complex and contentious groups, foremost of which is the P. picta and P. leucotis sensu lato (i.e., sensu Peters, 1937) complex. Here we also note others such as the P. melanura complex. Population-level sampling is especially relevant in a radiation as rapid as that of Pyrrhura . It is critical to understand how diversity within and among populations, as well as patterns of introgression and gene flow among them, can improve decisions about species limits and relationships. Concerning P. picta and P. leucotis sensu lato, we note that our data at best provide weak support for the taxa subsumed under the name P. picta by Peters (1937) as monophyletic, noting that Peters’ (1937) long since entrenched view had no accompanying support. This in turn suggests the merit of earlier suggestions to revisit the breaking up of P. picta and P. leucotis ( Joseph, 2000, 2002; Ribas et al., 2006). Concomitantly, it questions the persistent recognition of P. picta as polytypic and inclusion of such divergent taxa as caeruleiceps within it at subspecies rank by, for example, Gill et al. (2021) and Remsen et al. (2024). Similarly, and strictly speaking, our data offer ambiguous support for P. leucotis as Peters (1937) construed it, i.e., despite being closely related we do not find strong support for P. leucotis and P. griseipectus as sister taxa. We do nonetheless see strong support for a geographical grouping of western Amazonian taxa (roseifrons, peruviana ) in our data and much weaker support for other geographical groupings such as that of northwestern South America-Central America (eisenmanni, subandina, caeruleicep s) and, potentially, northern South America ( picta , emma) and central Amazonia (lucianii, amazonum ). Determining whether these geographical patterns also correspond to phylogenetic and taxonomic groupings warrants specific attention in future work. Compounding the issue is the recognition of more taxa within the group in recent decades, some of which we have included but many we have not ( Delgado, 1985; Ridgely and Gwynne, 1989; Joseph, 2002; Gaban-Lima and Raposo, 2016; Arndt and Wink, 2017).