Otidae is a clade that includes the superorders Otidimorphae and Strisores. It was identified in 2014 by genome analysis. Earlier it was thought that Strisores was closely related to birds such as pigeons, flamingos, tropicbirds, and the sunbittern and kagu in the taxon Metaves, but subsequent work has provided evidence that Metaves is polyphyletic. Although analyses of genome data provided relatively high support for monophyly of Otidae, indicating that it is sister to all other Passerea clades, other analyses of large data matrices have not recovered a clade comprising Otidimorphae and Strisores, raising questions about the monophyly of Otidae.
The mesites (Mesitornithidae) are a family of birds that are part of a clade (Columbimorphae) that include Columbiformes and Pterocliformes. They are smallish flightless or near flightless birds endemic to Madagascar. They are the only family with more than two species in which every species is threatened.
Neoaves is a clade that consists of all modern birds with the exception of Palaeognathae and Galloanserae. This group is defined in the PhyloCode by George Sangster and colleagues in 2022 as "the most inclusive crown clade containing Passer domesticus, but not Gallus gallus". Almost 95% of the roughly 10,000 known species of extant birds belong to the Neoaves.
Mirandornithes is a clade that consists of flamingos and grebes. Many scholars use the term Phoenicopterimorphae for the superorder containing flamingoes and grebes.
Aequornithes, or core water birds, are defined in the PhyloCode as "the least inclusive crown clade containing Pelecanus onocrotalus and Gavia immer".
The order Falconiformes is represented by the extant family Falconidae and a handful of enigmatic Paleogene species. Traditionally, the other bird of prey families Cathartidae, Sagittariidae (secretarybird), Pandionidae (ospreys), Accipitridae (hawks) were classified in Falconiformes. A variety of comparative genome analyses published since 2008, however, found that falcons are part of a clade of birds called Australaves, which also includes seriemas, parrots and passerines. Within Australaves falcons are more closely related to the parrot-passerine clade than they are to the seriemas. The hawks, vultures and owls are placed in the clade Afroaves.
Strisores, sometimes called nightbirds, is a clade of birds that includes the living families and orders Caprimulgidae, Nyctibiidae (potoos), Steatornithidae (oilbirds), Podargidae (frogmouths), Apodiformes, as well as the Aegotheliformes (owlet-nightjars) whose distinctness was only recently realized. The Apodiformes and the Aegotheliformes form the Daedalornithes.
Australaves is a clade of birds, defined in 2012, consisting of the Eufalconimorphae as well as the Cariamiformes. They appear to be the sister group of Afroaves. This clade was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Cariama cristata and Passer domesticus".
Afroaves is a clade of birds, consisting of the kingfishers and kin (Coraciiformes), woodpeckers and kin (Piciformes), hornbills and kin (Bucerotiformes), trogons (Trogoniformes), cuckoo roller (Leptosomiformes), mousebirds (Coliiformes), owls (Strigiformes) and raptors (Accipitriformes). The most basal clades are predatory, suggesting the last common ancestor of Afroaves was also a predatory bird. This group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Accipiter nisus, Colius colius, and Picus viridis, but not Passer domesticus".
Telluraves is a recently defined clade of birds defined by their arboreality. Based on most recent genetic studies, the clade unites a variety of bird groups, including the australavians as well as the afroavians. This grouping was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Accipiter nisus and Passer domesticus". They appear to be the sister group of the Phaethoquornithes.
Columbea is a clade suggested by genome analysis that contains Columbiformes, Pteroclidae (sandgrouse), Mesitornithidae (mesites) and Mirandornithes. Until their recent placement as the sister taxon to Passerea, in the last decade various genetic analysis found them to be in the obsolete clade Metaves.
Eurypygimorphae or Phaethontimorphae is a clade of birds that contains the orders Phaethontiformes (tropicbirds) and Eurypygiformes recovered by genome analysis. The relationship was first identified in 2013 based on their nuclear genes. This group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Phaethon aethereus, Eurypyga helias, and Rhynochetos jubatus". Historically these birds were placed at different parts of the tree, with tropicbirds in Pelecaniformes and the kagu and sunbittern in Gruiformes. Some genetic analyses have placed the eurypygimorph taxa in the controversial and obsolete clade Metaves, with uncertain placement within that group. More recent molecular studies support their grouping together in Eurypygimorphae, which is usually recovered as the sister taxon to Aequornithes within Ardeae.
Otidimorphae is a clade of birds that contains the orders Cuculiformes (cuckoos), Musophagiformes (turacos), and Otidiformes (bustards) identified in 2014 by genome analysis. George Sangster and colleagues in 2022 named the clade uniting turacos and bustards as Musophagotides, defining it in the PhyloCode as "the least inclusive crown clade containing Otis tarda and Musophaga violacea, but not Grus grus or Mesitornis variegatus".
Phaethoquornithes is a clade of birds that contains Eurypygimorphae and Aequornithes, which was first recovered by genome analysis in 2014. Members of Eurypygimorphae were originally classified in the obsolete group Metaves, and Aequornithes were classified as the sister taxon to Musophagiformes or Gruiformes.
Eucavitaves is a clade that contains the order Trogoniformes (trogons) and the clade Picocoraciae. The group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Trogon viridis and Picus viridis". The name refers to the fact that the majority of them nest in cavities.
Cavitaves is a clade that contains the order Leptosomiformes and the clade Eucavitaves. This group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Leptosomus discolor and Picus viridis". The name refers to the fact that the majority of them nest in cavities.
Picocoraciae is a clade that contains the order Bucerotiformes and the clade Picodynastornithes supported by various genetic analysis and morphological studies. While these studies supported a sister grouping of Coraciiformes and Piciformes, a large scale, sparse supermatrix has suggested alternative sister relationship between Bucerotiformes and Piciformes instead. This group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Buceros rhinoceros, Coracias garrulus, and Picus viridis".
Columbimorphae is a clade/superorder discovered by genome analysis that includes birds of the orders Columbiformes, Pterocliformes (sandgrouse), and Mesitornithiformes (mesites). This group was defined in the PhyloCode by George Sangster and colleagues in 2022 as "the least inclusive crown clade containing Columba oenas, Mesitornis variegatus, and Pterocles alchata". Previous analyses had also recovered this grouping, although the exact relationships differed. Some studies indicated a sister relationship between sandgrouse and pigeons while other studies favored a sister grouping of mesites and sandgrouse instead. This sister relationship of the sandgrouses and mesites was named by George Sangster and colleagues in 2022 as the clade Pteroclimesites and defined in the PhyloCode as "the least inclusive crown clade containing Mesitornis variegatus and Pterocles alchata".
Vanescaves is a probable clade of strisorean birds that include the clades Steatornithiformes, Nyctibiiformes, Podargiformes (frogmouths), and Apodimorphae. Some molecular studies do support the grouping of these birds, others offer conflicting positions of the non-apodimorphaean strisoreans. In 2019 the authors Chen et al. performed a combined analysis using 2289 ultra-conserved elements [UCEs], 117 morphological characters from extant and fossil taxa found support in this clade. The authors then proposed to name this group, which its meaning is Latin for "vanish birds" in reference to the disparate nature of their geographic distribution, as well as to the poem "A Route of Evanescence" by the American poet Emily Dickinson which features a hummingbird as the main subject. In 2020 Chen & Field named the two major subclades of this group, with Sedentaves and Letornithes for their crown-groups.
Litusilvanae is a proposed clade of birds, position as the sister clade to Aequorlitornithes. This clade comprises Gruimorphae and Strisores. While different lines of evidence from molecular, morphology and the fossil record has found support in the clades Gruimorphae and Strisores Wu et al. (2024) was the first to find support in such a novel sister group relationship between these two taxa.
