Article

The complete mitochondrial genome of an agamid lizard from the Afro-Asian subfamily agaminae and the phylogenetic position of Bufoniceps and Xenagama

Museum of Vertebrate Zoology, 3101 Valley Life Science Building, University of California, Berkeley, CA 94720, USA.
Molecular Phylogenetics and Evolution (Impact Factor: 3.92). 07/2006; 39(3):881-6. DOI: 10.1016/j.ympev.2005.08.020
Source: PubMed

ABSTRACT

Squamate reptiles are traditionally divided into six groups: Iguania, Anguimorpha, Scincomorpha, Gekkota (these four are lizards), Serpentes (snakes), and Amphisbaenia (the so-called worm lizards). The Iguania is recognized as having two major lineages the Iguanidae and Acrodonta (Agamidae and Chamaeleonidae). Currently, there are complete mitochondrial genomes from three Anguimorpha (Kumazawa, 2004; Kumazawa and Endo, 2004), two from the Scincomorpha (Kumazawa, 2004; Kumazawa and Nishida, 1999), one from Gekkota (Macey et al., 2005) two from Serpentes (Kumazawa, 2004; Kumazawa et al., 1998) and 12 from Amphisbaenia (Macey et al., 2004). In addition, two representatives of the Iguanian family Iguanidae (Janke et al., 2001; Kumazawa, 2004) have been sequenced. Its' sister taxon, the Acrodonta, consists of seven monophyletic groups-the family Chamaeleonidae and six distantly related subfamilies of the family Agamidae (Macey et al., 2000b). Currently, the only acrodont lineage sequenced for the complete mitochondrial genome is Pogona vitticeps from the Australasian agamid subfamily Amphibolurinae (Amer and Kumazawa, 2005a). Here, we report the complete mitochondrial genome of Xenagama taylori, a North African representative of the agamid subfamily Agaminae and compare it to P. vitticepes. The agamid lizard genus Xenagama is distributed in a restricted region of the Horn of Africa in northwestern Somalia and adjacent eastern Ethiopia as shown in Fig. 1, with two species currently recognized (Moody, 1980; Wermuth, 1967). In addition, we report a segment of the mitochondrial genome of Bufoniceps laungwalansis spanning from nad1 to cox1. The monotypic genus Bufoniceps is restricted to the Thar Desert, Jaisalmer District, Rajasthan State, India and adjacent Pakistan (Fig. 1). Both Bufoniceps and Xenagama belong to the subfamily Agaminae and are poorly understood phylogenetically. These genera were not represented in the most recent molecular systematic study of the Agamidae (Macey et al., 2000b). Bufoniceps was originally described as a member of the West Asian genus Phrynocephalus (Sharma, 1978), and later placed in its' own genus (Arnold, 1992) because morphological data suggested it is the sister taxon to Phrynocephalus (Arnold, 1999). Xenagama was previously considered part of the Agama complex before the allocation of its member species to several genera (see, Moody, 1980).

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Available from: James A Schulte II, Jan 25, 2014
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    • "Our divergence time estimates and those of two published studies on agamid lizards, suggest the origin of Pseudotrapelus occurred around 15–19 Mya (Macey et al., 2006;Leaché et al., 2014; Table 1). Our calibrations support the suggested role of the Gomphotherium land bridge between Eurasia–Arabia–Africa (18 Mya;Tchernov, 1992;Rögl, 1999) in the evolutionary diversification of Agamidae, as suggested by previous studies.Joger (1991)suggested this as a potential dispersal route for agamids from Asia into Arabia and later into Africa during the Miocene; whereasMacey et al. (2006)suggested an Afro-Arabian origin and the role of this land bridge as the later of two possible dispersal routes into Asia. The early-Miocene separation at 18 Mya (Table 1; Fig. 5) between the Arabian and African groups may correspond to the expansion of the Red Sea. "

    Full-text · Dataset · Jan 2016
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    • "Our divergence time estimates and those of two published studies on agamid lizards, suggest the origin of Pseudotrapelus occurred around 15–19 Mya (Macey et al., 2006;Leaché et al., 2014; Table 1). Our calibrations support the suggested role of the Gomphotherium land bridge between Eurasia–Arabia–Africa (18 Mya;Tchernov, 1992;Rögl, 1999) in the evolutionary diversification of Agamidae, as suggested by previous studies.Joger (1991)suggested this as a potential dispersal route for agamids from Asia into Arabia and later into Africa during the Miocene; whereasMacey et al. (2006)suggested an Afro-Arabian origin and the role of this land bridge as the later of two possible dispersal routes into Asia. The early-Miocene separation at 18 Mya (Table 1; Fig. 5) between the Arabian and African groups may correspond to the expansion of the Red Sea. "
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    ABSTRACT: Abstract Since the Oligocene, regions adjacent to the Red Sea have experienced major environmental changes, from tectonic movements and continuous geological activity to shifting climatic conditions. The effect of these events on the distribution and diversity of the regional biota is still poorly understood. Agamid members of the genus Pseudotrapelus are diurnal, arid-adapted lizards distributed around the Red Sea from north-eastern Africa, across the mountains and rocky plateaus of the Sinai and Arabian Peninsulas northwards to Syria. Despite recent taxonomic work and the interest in the group as a model for studying biogeographic and diversity patterns of the arid areas of North Africa and Arabia, its taxonomy is poorly understood and a comprehensive phylogeny is still lacking. In this study, we analyzed 92 Pseudotrapelus specimens from across the entire distribution range of the genus. We included all known species and subspecies, and sequenced them for mitochondrial (16S, ND4 and tRNAs) and nuclear (MC1R, c-mos) markers. This enabled us to obtain the first time-calibrated molecular phylogeny of the genus. We used gene trees, species trees and coalescent-based methods for species delimitation. Our results revealed Pseudotrapelus as a monophyletic genus comprised of two major clades and six independently evolving lineages. These lineages correspond to the five currently recognized species and a sixth lineage relating to the synonymized P. neumanni. The subspecific validity of P. sinaitus werneri needs further assessment as it does not form a distinct cluster relative to P. s. sinaitus. The onset of Pseudotrapelus diversification is estimated to have occurred in Arabia during the late Miocene. Radiation events have likely resulted from the continued geological instability, sea level fluctuations and climatic changes within the region.
    Full-text · Article · Jan 2016 · Molecular Phylogenetics and Evolution
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    • "The oldest fossil records of unambiguous crown acrodontans consist of uromastycines from the early Eocene of Europe and Asia [31,47], Barbaturex in the late middle Eocene of Asia and possibly the lineage including extant Leiolepis from the late Eocene of North America [24]. The first occurrence of the clade including agamines, draconines and amphibolurines may be early middle Eocene [32], but the late middle Eocene age of the Pondaung record precedes the first occurrences of crown members of this clade, which are early Neogene in age, consistent with molecular divergence estimates [48]. "
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