Tuesday, November 1, 2022

[Ornithology • 2022] Otus bikegila • A New Species of Scops-owl (Strigiformes: Strigidae) from Príncipe Island (Gulf of Guinea, Africa) and Novel insights into the Systematic Affinities within Otus


 Otus bikegila
Melo, Freitas, Verbelen, da Costa, Pereira, Fuchs, Sangster, Correia, de Lima & Crottini, 2022 
 
Principe Scops-Owl | Kitóli-do-príncipe || Mocho-do-príncipe || DOI: 10.3897/zookeys.1126.87635
Original artwork by Marco N. Correia.

Abstract
A new species of scops-owl (Aves, Strigiformes, Strigidae, Otus) is described from Príncipe Island, São Tomé and Príncipe (Gulf of Guinea, Africa). This species was discovered for science in 2016, although suspicions of its occurrence gained traction from 1998, and testimonies from local people suggesting its existence could be traced back to 1928. Morphometrics, plumage colour and pattern, vocalisations, and molecular evidence all support the species status of the scops-owl from Príncipe, which is described here as Otus bikegila sp. nov. Phylogenetic analyses suggest that this species descended from the first colonisation of the Gulf of Guinea islands, being sister to the clade including the mainland African Scops-Owl O. senegalensis, and the island endemics Sao Tome Scops-Owl O. hartlaubi and Pemba Scops-Owl O. pembaensis. The most diagnostic trait in the field is its unique call which, curiously, is most similar to a distantly related Otus species, the Sokoke Scops-Owl O. ireneae. The new species occurs at low elevations of the old-growth native forest of Príncipe, currently restricted to the south of the island but fully included within Príncipe Obô Natural Park. Otus bikegila sp. nov. takes the number of single-island endemic bird species of Príncipe to eight, further highlighting the unusually high level of bird endemism for an island of only 139 km2.

Keywords: Biodiversity, endemism, exploration, Gulf of Guinea, integrative taxonomy, Otus bikegila sp. nov., Prin­cipe Scops-Owl, systematics


The candidate species of  Otus from Príncipe
 A female specimen MHNC-UP-AVE7000, showing colouration in life (available also in the Macaulay library (ML): ML470442301; grey-brown morph) B female (left, sample P9-037) and male (right, sample P9-038) grey-brown morphs captured at Boca do Inferno on January 28, 2019 (ML470438621) C rufous morph individual photographed at Ribeira Porco area on July 04, 2016 D daytime sighting of a grey-brown morph individual between Rio São Tomé and Ribeira Porco on January 19, 2019 (ML470443361, only the rufous upperparts are clearly seen) E grey-brown morph individual photographed in the Ribeira Porco area on January 21, 2019 F fully developed brood patch of a female rufous morph (sample P8-001) captured in the Ribeira Porco area on January 20, 2019 (ML470440211). ML – Macaulay Library.
Photographs: A – HP B, D, F – MM and BF C – PV E – Paul van Giersbergen.

 Otus bikegila sp. nov.

Diagnosis: The new species (Figs 2, 9) is assigned to the genus Otus based on genetic and morphological similarities to other known species of this genus. Phylogenetic analyses place it within the Afro-Palearctic clade, making generic placement unambiguous. Placement of the new species in Otus is further supported by its morphological characters: small size, distinctive ear-tufts, facial disc, short rounded wings, and short tail. The new species differs from the other described taxa of the Afro-Palearctic Otus clade (O. hartlaubi, O. senegalensis, including O. s. feae sometimes treated as a distinct species, O. pembaensis, O. pamelae, O. scops, O. brucei) by high genetic differentiation (pairwise ND2 distance ranging from 4.1% to 9.1%), by the lack of haplotype sha­ring at the KIAA1239 and TGFB2 nuclear markers, as well as from a combination of morphological, genetic and natural history (bioacoustics) traits.

Principe Scops-Owl  Otus bikegila sp. nov. from Príncipe Island, Africa.
 Left: Adult rufous morph in the typical posture. Right: Adult grey-brown morph in a stress posture, when it raises the ear tufts to increase the efficiency of camouflage.
Original artwork by Marco N. Correia.

Etymology: 
The species name is a patronym honouring Ceciliano do Bom Jesus, known as ‘Bikegila’ (Suppl. material 5). The species epithet name is intentionally defined as an invariable noun in apposition (not a noun in the genitive case) for better pronunciation; no confusion with the species authority is possible because the noun is an oral nickname.

Bikegila, a native of Príncipe Island, began the ‘Príncipe Scops-Owl saga’ in 1998, when he shared with MM reports of two sightings of birds that looked like owls in parrot nests. Since then, Bikegila took part in every field effort that led to the bird’s discovery for science; he also led the capture of all sampled individuals, including the holotype, which required ingenious ways to erect canopy nets. For almost 25 years, Bikegila has put all his resources, including bottomless fieldwork skills and a vast knowledge of Príncipe, towards the successful completion of innumerable research projects in a terrain that the collector José Correia considered to be the “bad among the bad or the worse among the worse” [sic] (Diary, 2 September 1928, Archives AMNH, New York). Besides his skills, Bikegila’s “cheerful temperament, possibly the first requirement for an undertaking in inhospitable regions” (von Humboldt 1841), coupled with an unbeatable gift for story-telling and an underlying quiet wisdom, contributes as much to making the expeditions he leads memorable and successful. A former parrot harvester, Bikegila became a warden of Prín­cipe Obô Natural Park soon after its creation; he is now a much sought-after nature guide.

We believe that most field researchers are grateful to the ‘Bikegilas’ with whom they are/were honoured to work with. As such, the name is also in recognition of all the people, around the world, who through their deep relationship with and knowledge of the regions they inhabit, play key roles in the description of new species and of new sites to science.

Common name: We propose the English common name Principe Scops-Owl, the name for São Tomé and Príncipe as Kitóli-do-príncipe, and the name for the Portuguese list of the birds of the world as Mocho-do-príncipe. All common names refer to Príncipe Island, from where it is endemic.


Martim Melo, Bárbara Freitas, Philippe Verbelen, Sátiro R. da Costa, Hugo Pereira, Jérôme Fuchs, George Sangster, Marco N. Correia, Ricardo F. de Lima and Angelica Crottini. 2022. A New Species of Scops-owl (Aves, Strigiformes, Strigidae, Otus) from Príncipe Island (Gulf of Guinea, Africa) and Novel insights into the Systematic Affinities within OtusZooKeys. 1126: 1-54. DOI: 10.3897/zookeys.1126.87635

Resumo: Descrevemos uma nova espécie de mocho-de-orelhas ou kitóli (Strigiformes: Strigidae: Otus) da Ilha do Príncipe, São Tomé e Príncipe (Golfo da Guiné, África). Esta espécie foi descoberta para a ciência apenas em 2016, embora suspeitas da sua existência tenham ganho força a partir de 1998, e testemunhos de habitantes locais sobre a sua ocorrência já estarem documentados em 1928. A morfometria, a cor e padrão da plumagem, as vocalizações e dados moleculares demonstram que esta população de mocho no Príncipe é uma espécie nova, que foi batizada de mocho-do-príncipe (lista mundial) ou kitóli-do-príncipe (nome nacional), Otus bikegila sp. nov. As análises filogenéticas indicam que esta espécie descende da primeira colonização das ilhas do Golfo da Guiné, sendo irmã do clado que inclui o mocho-d’ore­lhas-africano O. senegalensis, do continente, o mocho-de-são-tomé (ou kitóli-de-são-tomé) O. hartlaubi e o mocho-de-pemba O. pembaensis, ambos endémicos das ilhas que lhes dão o nome. No campo, a característica mais diagnóstica é o seu canto único que, curiosamente, é mais parecido com o da espécie de Otus mais afastada, o mocho-de-sokoke O. ireneae. A nova espécie ocorre nas zonas baixas da floresta nativa do Príncipe, atualmente restrita ao sul da ilha, mas totalmente inserida no Parque Natural do Obô do Príncipe. Otus bikegila sp. nov. eleva o número de espécies de aves endémicas restritas ao Príncipe para oito, sublinhando ainda mais o nível extremamente elevado de aves endémicas para uma ilha de apenas 139 km2.
Palavras-chave: Biodiversidade, endemismo, exploração, Golfo da Guiné, Kitóli-do-príncipe, Mocho-do-príncipe, Otus bikegila sp. nov., sistemática, taxonomia integrada