The 46 Orders











As mentioned earlier, Jarvis et al. (2014) found the Strigiformes closer to the Picimorphae than to the Accipitrimorphae. However, support for this was not that strong, and some trees had the Strigiformes closer to the Accipitrimorphae. For that reason, I'm not including the Strigiformes in either the Accipitrimorphae or Picimorphae at this time.

The fossil record of the owls dates back to the Paleocene, both in Eurpoe and North America, but no Paleogene fossils have been found from the Southern Hemisphere (Mayr, 2009).

Tytonidae: Barn Owls Mathews, 1912 (1866)

2 genera, 18 species HBW-5

The Eastern Barn-Owl has been split as a separate species as in Christidis and Boles (2008). This had previously been called Tyto javanica based on Wink et al. (2004b). However, there seems to have been a problem with the DNA sample, and javanica is most likely a subspecies of Common Barn-Owl, Tyto alba. Thus the Eastern Barn-Owl becomes Tyto delicatula. Some other Barn Owl splits may be needed. In particular, the American subspecies could be split at Tyto furcata.

Following H&M-4 (Dickinson and Remsen, 2013) and König and Weick (2008), the poorly known Congo Bay-Owl has been moved to Tyto from Phodilus.

Strigidae: Typical Owls Leach, 1820

31 genera, 215 species HBW-5

The overall organization is based on Wink et al. (2008) and Fuchs et al. (2008). The typical owls are divided into three subfamilies: Ninoxinae, Surniinae, and Striginae. These are further divided into tribes, although that is almost overkill as the tribes are barely larger than the main genus, if at all.

Within Ninoxinae, the position of Uroglaux and Sceloglaux is unresolved, although they are believed to be near Ninox on morphological grounds.

Strigidae tree There are four main clades in Surniinae. There's no molecular evidence concerning Xenoglaux, but it is believed close to Micrathene, which seems to be basal in Surniinae. Heteroglaux is most likely sister to Athene, which it has sometimes been considered part of.

The treatment of the Glaucidium complex is a bit novel. The basic structure comes from Wink et. al. (2008). Although their taxon sampling is a bit sparse, it suggest five clades in the Glaucidium complex. I've applied the old name Smithiglaux (Bonaparte 1854) to the basal clade, which consists of two African species. The next clade gets the name Taenioglaux, which has recently been revived (e.g., König and Weick, 2008) for Taenioglaux plus Smithiglaux. Next comes the monotypic Surnia, then Glaucidium itself. Glaucidium consists of an Old World clade of owlets (Glaucidium proper) and a New World clade of pygmy-owls. The latter could take the name Phalaenopsis (Bonaparte 1854). For now, I am treating it as a subgenus to maintain consistency with AOU, although a separate genus would make the phylogeny more transparent.

The rest of the owls are in the subfamily Striginae. Otus has been split into the Old World Otini scops-owls and New World Megascopini based on genetic data (e.g., Wink and Heidrich, 1999; Wink et al., 2004b, 2008; Fuchs et al. 2008). Surprisingly, they are not sister groups. Otini consists of the Old World Otus and Pyrroglaux. It is not clear that the latter belongs here, but it seems more likely than the alternatives. The Giant Scops-Owl, Mimizuku gurneyi, is considered part of Otus (Miranda et al., 1997, 2011). I've rearranged Otus some based on Fuchs et al. (2008), Pons et al. (2013), Wink et al. (2008) and HBW-5 (del Hoyo et al., 1999), but a true species-level phylogeny is not available.

The three extinct owls from the Mascarenes are in the genus Mascarenotus, which is thought to be closely related to Otus, or may even be embedded in it.

The Megascopini come after the Asionini. The species arrangement is based on Dantas et al. (2016). They found the Puerto Rican Screech-Owl is sister to Psiloscops, albeit distantly related. Margarobyas is probably close to Megascops. Note that the genus name Gymnoglaux has been replaced by Margarobyas. This is because the type of Gymnoglaux is nudipes, not lawrencii (see Olson and Suárez, 2008). Now that the Puerto Rican Screech-Owl has been moved next to Psiloscops, it takes the genus name Gymnasio (Bonaparte, 1854), which has priority over Gymnoglaux (Cabanis, 1855).

There has been resistance to separating the Flammulated Owl from Otus with Megascops, probably because it is too different from the screech-owls. Nonetheless, the genetic data group it with Megascops, albeit distantly. For that reason it gets its own genus Psiloscops (Coues 1899) as in König and Weick. I place it basally in Megascopini.

After Pulsatricini, comes Strigini. Jubula is conventionally place here, although its exact affinities remain unclear. My treatment of Strix is a bit unusual. Wink et al. (2008) found two clades in Strix. One is a Holarctic/Old World clade, the other consists of New World species. Some of the New World species have sometimes been separated as Ciccaba, but it has often been objected that they are not distinct from other New World Strix. Here I put all of the New World Strix in an expanded Ciccaba. That leaves the holarctic Great Gray Owl as the only Strix present in the New World. Finally, the African Wood-Owl, Strix woodfordii, which has sometimes been considered close to Ciccaba in the narrow sense, belongs in the Old World clade.

The last clade is Bubonini. DNA is showing that the old generic limits don't work, and the tendency has been to merge everything into Bubo. I think this hides the phylogeny too much. An improvement would be to use two genera, Bubo as constituted here and Ketupa. However, given that some of these species (and even former genera) are mophologically distinct, I think a better solution is to break the clade sister to Bubo into three genera.

We then have 4 genera in Bubonini: Bubo, Nyctaetus (Le Maout 1853), Scotopelia and Ketupa. Ketupa has been expanded with some species that may be closely related (more data is needed). Scotopelia retains its traditional limits. Shelley's and Verreaux's Eagle-Owls are in their own clade, Nyctaetus. It's unclear which clade the Dusky and Akun Eagle-Owls belong in, so I've left them in Bubo for now. Although the Snowy Owl has been considered to be in its own genus, Nyctea, it is actually in Bubo proper, sister to the Great Horned Owl.

The Bermuda Saw-whet Owl, Aegolius gradyi, has been added as it seems to have become extinct in historical times (Olson, 2012).

Northern Boobook, Ninox japonica, and Chocolate Boobook, Ninox randi, have been split from Brown Hawk-Owl, Ninox scutulata, following King (2002).

Rasmussen et al. (2012) re-examined the Philippine Hawk-Owl complex. Their fieldwork turned up two new species in the complex. They argue that the complex consists of 7 species, and I follow their recommendations. This means that Philippine Hawk-Owl is replaced by:

Guatemalan Pygmy-Owl, Glaucidium cobanense has been split from Northern Pygmy-Owl, Glaucidium gnoma, due to substantial differences in vocalizations (Eisermann and Howell, 2011).

Socotra Scops-Owl, Otus socotranus, has been separated from the African Scops-Owl, Otus senegalensis, due to substantial differences in vocalizations (e.g., König and Weick, 2008). In fact, its calls are more similar to the Oriental Scops-Owl, Otus sunia. Pons et al. (2013) found it was closely related to O. sunia and O. insularis. The Arabian Scops-Owl, Otus pamelae, has also been separated from the African Scops-Owl, Otus senegalensis (Pons et al., 2013). The Negros Scops-Owl, Otus nigrorum, and Everett's Scops-Owl, Otus everetti have been split from Philippine Scops-Owl, Otus megalotis. See Miranda et al. (2011). Finally, the newly discovered Rinjani Scops-Owl, Otus jolandae, has been added to the list (Sangster et al., 2013).

Hume's Owl, Strix butleri, has been split into Omani Owl, Strix butleri, and Desert Owl, Strix hadorami based on Robb et al. (2013) and Kirwan et al. (2015). It's clear enough that there are at least two species here. It's somewhat less clear that they are hadorami and butleri, but it seems the best choice given current evidence.

The Cinereous Owl, Ciccaba sartorii has been split from Barred Owl, Ciccaba varia due to difference in both DNA and vocalizations. It is more closely related to the Fulvous Owl than to the Barred Owl (Barrowclough et al., 2011).

Ninoxinae: Hawk-owls Marks et al., 1999

Surniinae: Owlets and Pygmy-Owls Bonaparte, 1838

Subgenus Phalaenopsis

Striginae Leach, 1820

Otini: Scops-Owls Bonaparte, 1854

Asionini: Eared Owls Vigors, 1825

Megascopini: Screech-Owls Wink et al., 2008? Informal?

Both Megascopini and Pulsatrigini have been used by Wink et al. (2008), but do not seem to have been designated as new taxa, which is now required by the ICZN (since 1999). The spelling of Pulsatrigini has been corrected to Pulsatricini.

Pulsatricini Wink et al., 2008? Informal?

Strigini: Wood-Owls Leach, 1820

Bubonini: Eagle-Owls Vigors, 1825


Other than their ordering and associationg with the Piciformes, the treatment of much of the remaining non-passerine families is close to that of the Sibley-Monroe list. Changes over time have mostly involved whether to consider certain groups families or subfamilies.

The mousebirds, cuckoo roller, and trogons are placed in separate orders, as their affinities with the other Picimorphae are relatively distant. The hornbills, which are split into Bucorvidae (ground-hornbills) and Bucerotidae (hornbills) form a grouping with the hoopoes and woodhoopoes. The bee-eaters, rollers, ground-rollers, todies, motmots, and kingfishers form the Coraciiformes. The last group is the the Piciformes, which I take to include the “Galbuliformes”. They will be considered on a later page.

Jarvis et al. (2014) estimated the split between the Coraciiformes and Piciformes at around 40 mya. If their estimates are correct, this is by far the most recent ordinal-level split. If the estimate holds up, it might be worth thinking about merging them into one order. Indeed, even if the hornbills are also included, it would still be one of the most recent ordinal-level splits. There is some fossil evidence (Primobucco) that suggests the split occurred earlier (e.g., Clarke et al., 2009; Ksepka and Clarke, 2010). Or perhaps Primobucco, which was originally considered a puffbird, is from before the split between the two groups. This has to be considered due to differences between phylogenetic analysis of Clarke et al. (2009) and the DNA evidence.


The Coliiformes are a relict Afrotropical group consisting of 6 species in 2 genera. It wasn't always so. There's a fairly extensive fossil record from Europe and North America. Primitive Coliiformes (Sandcoleidae) are known from the early Eocence (48-56 mya). By the late Eocne, only modern forms are known (Mayr, 2009).

Coliidae: Mousebirds Sundevall, 1836

2 genera, 6 species HBW-6


The Cuckoo Roller was originally considered a cuckoo, some affinities with the rollers were noted, and it has more recently been considered its own family, Leptosomidae. Mayr (2008a) discusses some of the differences between the Cuckoo Roller and the true rollers. Darren Naish's comments on the Cuckoo Roller at Tetrapod Zoology are also worth reading.

This is another relict group, consisting of a single species from Madagascar and the Comoros. Fossils are again know from Europe and North America in the early and middle Eocene.

Leptosomidae: Cuckoo Roller Blyth, 1838

1 genus, 1 species HBW-6

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