Diversity, distribution and conservation of the terrestrial reptiles of Oman (Sauropsida, Squamata)

Abstract

In the present work, we use an exceptional database including 5,359 records of 101 species of Oman’s terrestrial reptiles together with spatial tools to infer the spatial patterns of species richness and endemicity, to infer the habitat preference of each species and to better define conservation priorities, with especial focus on the effectiveness of the protected areas in preserving this unique arid fauna. Our results indicate that the sampling effort is not only remarkable from a taxonomic point of view, with multiple observations for most species, but also for the spatial coverage achieved. The observations are distributed almost continuously across the two-dimensional climatic space of Oman defined by the mean annual temperature and the total annual precipitation and across the Principal Component Analysis (PCA) of the multivariate climatic space and are well represented within 17 out of the 20 climatic clusters grouping 10% of the explained climatic variance defined by PC1 and PC2. Species richness is highest in the Hajar and Dhofar Mountains, two of the most biodiverse areas of the Arabian Peninsula, and endemic species richness is greatest in the Jebel Akhdar, the highest part of the Hajar Mountains. Oman’s 22 protected areas cover only 3.91% of the country, including within their limits 63.37% of terrestrial reptiles and 50% of all endemics. Our analyses show that large areas of the climatic space of Oman lie outside protected areas and that seven of the 20 climatic clusters are not protected at all. The results of the gap analysis indicate that most of the species are below the conservation target of 17% or even the less restrictive 12% of their total area within a protected area in order to be considered adequately protected. Therefore, an evaluation of the coverage of the current network of protected areas and the identification of priority protected areas for reptiles using reserve design algorithms are urgently needed. Our study also shows that more than half of the species are still pending of a definitive evaluation by the International Union for Conservation of Nature (IUCN).

Systematics of the Saharo‐Arabian clade of the Palearctic naked‐toed geckos with the description of a new species ofTropiocolotesendemic to Oman

“…One of the problematic species of Tropiocolotes is the south Arabian endemic T. scorteccii . It ranges from western Yemen, through the Hadramaut (type locality) up to Duqm, Al Wusta Governorate, in east‐central Oman, including the Al‐Hallaniyah Island (Carranza et al., ; Gardner, ; Sindaco & Jeremčenko, ). Arnold () and later Baha El Din () found a high degree of morphological variability within T. scorteccii suggesting that, most probably, more than one species was included within this taxon.…”

“…The highest point is over 2,000 m and is located in the latter massif, where temperatures reach the lowest values of southern Oman (Sale, ). The Dhofar Mountains lie within the monsoon belt and most rain falls during the summer Monsoon in July and August and is responsible for the unique green vegetation on the south‐facing (sea) side of this mountain range (Carranza et al., ; Kwarteng, Dorvlo, & Kumar, ). The northern slopes across the whole mountain range are in rain shadow and, as a result, the north‐facing side of the Dhofar Mountains is much drier and less vegetated than the lush south‐facing one.…”

Hidden in the Arabian Mountains: Multilocus phylogeny reveals cryptic diversity in the endemicOmanosauralizards

“…The distribution of the two Omanosaura species as currently assessed by the IUCN Red List of Threatened Species (Soorae, Wilms, & Al Rasbi, ) is more restricted than our sampling locations and records for Omanosaura shown by Gardner () and Carranza et al. () ( O. cyanura CN706 and O. jayakari UAE17, UAE18, CN743 and CN276; Figure ), and reflect record gaps, rather than the true absence (Gardner, ). This can be associated with (i) the low number of expeditions to the Hajar Mountains until very recently and the inaccessibility of some of the areas, (ii) the lack of scientific attention given to this genus, and also (iii) with the general elusive nature of O. cyanura , which makes it particularly difficult to see and capture.…”

“…Omanosaura cyanura is a small‐bodied lizard, with SVL of about 60 mm, and presents a flattened head and body, with dorsal coloration that can be brown or blue, with a long electric blue tail, the feature to which it owes its name. Little is known about this lizard, which is normally spotted in wadis with vegetation and water, from sea level up to 2,400 m a.s.l (Carranza et al., ; Gardner, ). On the other hand, O. jayakari is the largest lacertid lizard in the Hajar Mountains, with SVL up to 200 mm.…”

Systematics of the Mesalina guttulata species complex (Squamata: Lacertidae) from Arabia with the description of two new species

“…Finally, as part of recent fieldwork in southeastern Arabia, some isolated populations of a new species resembling M. guttulata were discovered that differed morphologically from "true" M. guttulata from around the type locality in "lower Egypt (near Alexandria or Siwa)", suggesting the existence of yet a new unnamed species of the M. guttulata species complex in southern Arabia (referred to it as Mesalina sp. 1 by Carranza et al 2018).…”