Molecular systematics of social skinks: phylogeny and taxonomy of theEgerniagroup (Reptilia: Scincidae)

Abstract

The lizards of the Egernia group of Australia and Melanesia include some of the most distinctive members of the family Scincidae in morphology (including giant size, spinose scalation), ecology and behaviour. Social behaviour, including long-term recognition of individuals and kin, mate fidelity and home site fidelity, is amongst the most complex known in squamate reptiles and is the subject of an expanding number of studies. Lack of a sound phylogeny for the Egernia group has limited our ability to understand the evolution and patterns of variation in social behaviour within this group, and evidence for the monophyly of the largest genus, Egernia (64% of the species), has been lacking. We present data derived from nucleotide sequences that establish a phylogenetic framework for the Egernia group. We used two mitochondrial sequences, the protein-encoding ND4 gene and a ribosomal gene, 12s rRNA, and two nuclear sequences, the protein-encoding c-mos, and non-encoding intron 7 of b-fibrinogen. Our phylogenetic analyses show that Corucia of the Solomon Islands is the sister group of the rest of the Egernia group. The genus Egernia is paraphyletic, including four well-supported monophyletic units, one of which is the sister lineage of the Tiliqua lineage (Tiliqua plus Cyclodomorphus). We suggest a revised taxonomic scheme that recognizes the major monophyletic lineages in Egernia (s.l.) as distinct genera.

Geometric morphometric analysis of cranial variation in the Egernia depressa (Reptilia: Squamata: Scincidae) species complex

“…These groupings were later thought to be based on convergent characters, and therefore did not necessarily ref lect phylogenetic relationships (Chapple 2003). Recently, a molecular phylogenetic study (Gardner et al 2008) supported the latter view, and Egernia was divided into four genera (Egernia, Liopholis, Bellatorias, Lissolepis).…”

Revision of the Pygmy Spiny-tailed Skinks (Egernia depressa species-group) from Western Australia, with descriptions of three new species

“…For polymerase chain reaction (PCR) amplifi cations, 50-100 ng of the extracted total DNA samples were added to 50 μl reaction mixtures containing 2 or 4 mM MgCl 2 , 1X Taq DNA buffer, 0.2 mM each of dNTPs, 0.25 mM each primer and 0.75 unit of Promega Taq DNA Polymerase. The primers used for amplifi cation and direct sequencing of part of the mitochondrial ND4 gene are listed in Gardner et al (2008). Amplifi cation was carried out on a Corbett FTS-320 Thermal Sequencer and comprised a single cycle of denaturation for 3 min at 94°C, annealing for 45 s at 47°C or 55°C and extension for 1 min at 72°C, followed by 34 cycles of 94°C for 45 s, 47°C or 55°C for 45 s and 72°C for 1 min, ending with a single extension step of 72°C for 6 min.…”

“…Outgroup taxa were selected on the basis of the phylogenetic analysis of the Egernia group by Gardner et al (2008).…”

“…Scincid lizards of the genus Egernia Gray, 1839 (sensu Gardner et al 2008) are medium to largebodied Australian Egernia group skinks with moderate morphological diversity and a tendency towards sociality (Storr et al 1999;Chapple 2003). Many Egernia species rely on crevices for shelter in either rocks or trees, especially fallen logs.…”

Morphology and burrowing energetics of semi-fossorial skinks (Liopholis)

“…Burrowing is an important form of locomotion in reptiles (Lee, 1998) and one-third of Australian skinks are burrowing species that spend most of their lives underground (Wilson and Swan, 2013). The night skink (Liopholis striata) and the desert skink (Liopholis inornata) are nocturnal, semi-fossorial skinks from the genus Liopholis ( previously Egernia; Gardner et al, 2008). In their natural habitat they are important bioturbators that modify the desert environment and produce burrows that provide shelter for other fauna including prickly geckos (Heteronotia binoei), knob-tailed geckos (Nephrurus levis) and king brown snakes (Pseudechis australis) (Pianka and Giles, 1982).…”