Systematics, biogeography and evolution of Asaccus gallagheri (Squamata, Phyllodactylidae) with the description of a new endemic species from Oman

Abstract

The Hajar Mountains are the highest mountain range in eastern Arabia. Despite being classified as a mountain desert, it is considered one of the top biodiversity hotspots of Arabia. As a result of its relatively old geological origin, complex topography, environmental heterogeneity and geographic isolation from other mountain ranges, its fauna and flora have diversified significantly producing high levels of endemicity, particularly amongst reptiles. Several genetic studies indicate that this diversity may still be underestimated, especially within some groups containing morphologically similar species like the nocturnal geckos of the genus Asaccus. These have radiated extensively on both sides of the Gulf of Oman, in the Hajar Mountains and the Zagros Mountains of south-west Asia, and are a good example of the faunal affinities between these two mountain ranges. In the present work, we analyse A. gallagheri, the smallest species of the Arabian radiation, using an unprecedented sampling across its entire distribution range and an integrative approach combining morphological, macroecological and multilocus molecular data with the objective of clarifying its systematics and phylogeography. The results support the presence of two allopatric species within A. gallagheri that split approximately 6 Ma. The newly discovered species is endemic to the Eastern Hajars and is described herein mainly on the basis of its smaller size and high genetic divergence from A. gallagheri. The molecular analyses also uncovered remarkable levels of genetic diversity within both species. The present study highlights the diversity of the genus Asaccus in south-east Arabia and stresses its relevance from a conservation point of view.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:62EB3146-9F79-4857-8CC6-36FE235D84D4

Key words:

• Arabia
• biogeography
• endemicity
• geckos
• Hajar Mountains
• hypervolumes
• species delimitation
• taxonomy

Acknowledgements

We wish to thank Ali Alghafri, Sultan Khalifa, Hamed Al Furkani, Johnnes Els, Margarita Metallinou, Thomas Wilms, Jiri Smíd, Raquel Vasconcelos, Roberto Sindaco, Philip de Pous and Fèlix Amat for assisting in sample collection in the field. Special thanks are due to Saleh Al Saadi, Ahmed Said Al Shukaili, Mohammed Al Shariani, Ali Al Kiyumi, Mohammed Abdullah Al Maharmi and the other members of the Nature Conservation Department of the Ministry of Environment and Climate, Sultanate of Oman for their help and support. We also wish to thank the following people for their help with the shipment of tissue samples: J. Vindum from the California Academy of Sciences (CAS), USA; C. Spencer from the Museum of Vertebrate Zoology (MVZ), University of California, Berkeley, USA. Thanks also to Hessa Saif Al Shamsi for the Arabic translation. Specimens were collected and manipulated with the authorization and under control and permission of the governments of Oman (Ministry of Environment and Climate Affairs, MECA) and the United Arab Emirates (Environment and Protected Areas Authority, Government of Sharjah). Specimens were captured and processed following the guidelines and protocols stated in the collecting permits and agreements obtained from the competent authorities (see references below). Members of the government supervised collecting activities. All efforts were made to minimize animal suffering. All the necessary collecting and export permits for this study in Oman were issued by the Nature Conservation Department of the Ministry of Environment and Climate Affairs, Oman (Refs: 08/2005; 16/2008; 38/2010; 12/2011; 13/2013; 21/2013) and the research in the United Arab Emirates was done under the supervision and permission of the Environment and Protected Areas Authority, Government of Sharjah. This work was supported by the Ministerio de Economía y Competitividad, Spain (co-funded by FEDER) under grant numbers CGL2012-36970 and CGL2015-70390-P; Ministry of Environment and Climate Affairs under Grant number 22412027; Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya under grant number 2014-SGR-1532; MSR is funded by a FPI grant from the Ministerio de Economía y Competitividad, Spain (BES-2013-064248); PT is funded with a grant from Fundação para a Ciência e Tecnologia with reference SFRH/BPD/93473/2013.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental data

Supplemental data for this article can be accessed here: https://doi.org/10.1080/14772000.2017.1403496.

Additional information

Funding

This work was supported by the Ministerio de Economía y Competitividad, Spain (co-funded by FEDER) under [grant numbers CGL2012-36970], [grant numbers CGL2015-70390-P]; Ministry of Environment and Climate Affairs under [grant number 22412027]; Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya under [grant number 2014-SGR-1532]; MSR is funded by a FPI grant from the Ministerio de Economía y Competitividad, Spain [grant number BES-2013-064248]; PT is funded with a grant from Fundação para a Ciência e Tecnologia with reference [grant number SFRH/BPD/93473/2013].