Otus (bird)

Scops owls are typical owls in family Strigidae belonging to the genus ''Otus'' and are restricted to the Old World. ''Otus'' is the largest genus of owls with 59 species. Scops owls are colored in various brownish hues, sometimes with a lighter underside and/or face, which helps to camouflage them against the bark of trees. Some are polymorphic, occurring in a greyish- and a reddish-brown morph. They are small and agile, with both sexes being compact in size and shape. Female scops owls are usually larger than males.

For most of the 20th century, this genus included the American screech owls, which are now again separated in ''Megascops'' based on a range of behavioral, biogeographical, morphological and DNA sequence data.

Taxonomy

The genus ''Otus'' was introduced in 1769 by the Welsh naturalist Thomas Pennant for the Indian scops owl (''O. bakkamoena''). The name is derived from the Latin word ' and the Greek word ''ōtos'' meaning horned or eared owl (cf. οὖς, ὠτός, "ear"). The generic name ''Scops'' that was proposed by Marie Jules César Savigny in 1809 is a junior synonym and is derived from the Greek ''skōps'' meaning small kind of owl, Otus scops.

By the mid-19th century, it was becoming clear that ''Otus'' encompassed more than one genus. First, in 1848, the screech owls were split off as ''Megascops''. The white-faced owls of Africa, with their huge eyes and striking facial coloration, were separated in ''Ptilopsis'' in 1851. In 1854, the highly apomorphic white-throated screech owl of the Andes was placed in the monotypic genus ''Macabra''. ''Gymnasio'' was established in the same year for the Puerto Rican owl, and the bare-legged owl (or "Cuban screech owl") was separated in ''Gymnoglaux'' the following year; the latter genus was sometimes merged with ''Gymnasio'' by subsequent authors. The Palau scops owl, described only in 1872 and little-known to this day, was eventually separated in ''Pyrroglaux'' by Yoshimaro Yamashina in 1938.

In the early 20th century, the lumping-together of taxa had come to be preferred. The 3rd edition of the AOU checklist in 1910 placed the screech owls back in ''Otus''. Although this move was never unequivocally accepted, it was the dominant treatment throughout most of the 20th century. In 1988 it was attempted to resolve this by re-establishing all those genera split some 140 years earlier at subgenus rank inside ''Otus''. Still, the diversity and distinctness of the group failed to come together in a good evolutionary and phylogenetic picture, and it was not until the availability of DNA sequence data that this could be resolved. In 1999, a preliminary study of mtDNA cytochrome ''b'' across a wide range of owls found that even the treatment as subgenera was probably unsustainable and suggested that most of the genera proposed around 1850 should be accepted. Though there was some debate about the reliability of these findings at first, they have been confirmed by subsequent studies. In 2003, the AOU formally re-accepted the genus ''Megascops'' again.

Species

The genus ''Otus'' contains 59 species (including 3 extinct species):

* Giant scops owl, ''Otus gurneyi''
* White-fronted scops owl, ''Otus sagittatus''
* Reddish scops owl, ''Otus rufescens''
* Serendib scops owl, ''Otus thilohoffmanni''
* Sandy scops owl, ''Otus icterorhynchus''
* Sokoke scops owl, ''Otus ireneae''
* Andaman scops owl, ''Otus balli''
* Flores scops owl, ''Otus alfredi''
* Mountain scops owl, ''Otus spilocephalus''
* Javan scops owl, ''Otus angelinae''
* Mindanao scops owl, ''Otus mirus''
* Luzon scops owl, ''Otus longicornis''
* Mindoro scops owl, ''Otus mindorensis''
* São Tomé scops owl, ''Otus hartlaubi''
* Torotoroka scops owl, ''Otus madagascariensis'' – formerly included in ''O. rutilus''
* Rainforest scops owl, ''Otus rutilus''
* Mayotte scops owl, ''Otus mayottensis'' – formerly included in ''O. rutilus''
* Karthala scops owl, ''Otus pauliani''
* Anjouan scops owl, ''Otus capnodes''
* Moheli scops owl, ''Otus moheliensis''
*† Réunion scops owl, ''Otus grucheti'' – extinct, formerly placed in the genus ''Mascarenotus''
*† Mauritius scops owl, ''Otus sauzieri'' – extinct, formerly placed in the genus ''Mascarenotus''
*† Rodrigues scops owl, ''Otus murivorus'' – extinct, formerly placed in the genus ''Mascarenotus''
* Pemba scops owl, ''Otus pembaensis''
* Eurasian scops owl, ''Otus scops''
* Cyprus scops owl, ''Otus cyprius'' – formerly included in ''O. scops''
* Pallid scops owl, ''Otus brucei''
* Arabian scops owl, ''Otus pamelae''
* African scops owl, ''Otus senegalensis''
* Annobón scops owl, ''Otus feae'' – formerly included in ''O. senegalensis''
* Socotra scops owl, ''Otus socotranus''
* Oriental scops owl, ''Otus sunia''
* Ryūkyū scops owl, ''Otus elegans''
* Moluccan scops owl, ''Otus magicus''
* Wetar scops owl, ''Otus tempestatis''
* Sula scops owl, ''Otus sulaensis''
* Biak scops owl, ''Otus beccarii''
* Sulawesi scops owl, ''Otus manadensis''
*Banggai scops owl, ''Otus mendeni''
* Siau scops owl, ''Otus siaoensis''
* Sangihe scops owl, ''Otus collari''
* Mantanani scops owl, ''Otus mantananensis''
* Seychelles scops owl, ''Otus insularis''
* Nicobar scops owl, ''Otus alius''
* Simeulue scops owl, ''Otus umbra''
* Enggano scops owl, ''Otus enganensis''
* Mentawai scops owl, ''Otus mentawi''
* Rajah scops owl, ''Otus brookii''
* Indian scops owl, ''Otus bakkamoena''
* Collared scops owl, ''Otus lettia'' – formerly included in ''O. bakkamoena''
* Japanese scops owl, ''Otus semitorques'' – formerly included in ''O. bakkamoena''
* Sunda scops owl, ''Otus lempiji'' – formerly included in ''O. bakkamoena''
* Philippine scops owl, ''Otus megalotis''
* Negros scops owl, ''Otus nigrorum'' – formerly included in ''O. megalotis''
* Everett's scops owl, ''Otus everetti'' – formerly included in ''O. megalotis''
* Palawan scops owl, ''Otus fuliginosus''
* Wallace's scops owl, ''Otus silvicola''
* Rinjani scops owl, ''Otus jolandae'
* Palau scops owl, ''Otus podarginus'' – formerly placed in the monotypic genus ''Pyrroglaux''
* Principe scops owl, ''Otus bikegila''
Two extinct species are sometimes placed in the genus:
*† Madeiran scops owl, ''Otus mauli'' (extinct, c. 15th century)
*† São Miguel scops owl, ''Otus frutuosoi'' (extinct, c. 15th century)

An apparent ''Otus'' owl was heard calling at about 1,000 meters ASL south of the summit of Camiguin in the Philippines on May 14, 1994. No scops owls had previously known from this island, and given that new species of ''Otus'' are occasionally discovered, it may have been an undescribed taxon.

In July 2016, an unknown ''Otus'' species was photographed on Príncipe. The image was published on Ornithomedia. Dubbed '' Otus bikegila'', it was formally described in 2022.

Formerly placed here

As noted above, the fossil record of scops owls gives an incomplete picture of their evolution at present. While older sources cite many species of supposed extinct ''Otus'' (or ''"Scops"''), these are now placed in entirely different genera:
* ''"Otus" henrici'' was a barn owl of the genus '' Selenornis''
* ''"Otus" providentiae'' was a burrowing owl, probably a paleosubspecies
* ''"Otus" wintershofensis'' may be close to extant genus '' Ninox'' and some material assigned to it belongs into '' Intutula''
* ''"Scops" commersoni'' is a junior synonym of the recently extinct Mauritius owl, referring to pictures and descriptions which mention ear tufts; the subfossil material of this species had been erroneously assigned to tuftless owls.

Evolution

The evolutionary relationships of the scops and screech owls are not entirely clear. What is certain is that they are very closely related; they may be considered sister lineages which fill essentially the same ecological niche in their allopatric ranges. A screech-owl fossil from the Late Pliocene of Kansas – which is almost identical to eastern and western screech owls – indicate a long-standing presence of these birds in the Americas, while coeval