Molecular Phylogeny Of Gekkotan Lizards

Gekkotan lizards are composed of Eublepharidae, Pygopodidae and Gekkonidae, and current estimates of gekkotan diversity recognize approximately 1110 species in 116 genera. The morphological characters as well as biological and paleontological findings were employed for analysis of systematic relationship in early times. According to the cladistic analysis, which has been introduced since the middle period of 20 century, Eublepharidae was the most primiteve clade and Gekkonidae was differentiated latest. New evidence of chromosome, protein and nucleic acid has been employed to deduce and validate the interrelationships of the taxa since 1980s. C-mos nuclear and 12S rRNA mitochondrial DNA were employed as genetic markers to deduce (he phylogeny of gekkotan lizards in the present study1. Phylogenetic relationships among the higher taxonomic categories of gekkotan lizardsC-mos gene appears very useful for resolving phylogenetic divergences among higher level vertebrate taxa including reptiles. We selected this gene for the phylogenetic relationship analysis among the higher taxonomic categories of gekkotan lizards. Samples were selected to include representatives of all previously recognized higher order groups of gekkotans and to include wide geographic representation. Samples representing 30 genera were collected from China, India, Malaysia, the United States, Mexico, Puerto Rico, South Africa, Kenya, Namibia, Mozambique, Kiribati, Madagascar, Australia, and New Caledonia. The aligned length of 378 base pair (bp) partial sequences was available for the C-mosDNA. Sequences of an additional 11 gekkotan genera retrieved from GenBank were also used in the analysis.(1) Gekkota as well as Eublepharidae, Gekkonidae, Pygopodidae, Pygopodinae, Diplodactylini (sensu Kluge, 1987) are monophyletic;(2) Diplodactylinae and Carphodactylini are not monophyletic, and we propose to recognize three families within the Pygopodidae sensu Kluge (1987): Pygopodidae, Carphodactylidae and Diplodactylidae.(3) The position ofColeonyx as the sister group of the other genera, Holodactylus and Eublepharis is different from most of previous results;(4) Our results support the hypothesis that the early eladogenesis of the Gekkota was associated with the split of Eastern Gondwanaland from Western Gondwanaland. Divergences within living genera in the Eublepharidae .and the Eastern Gondwana lineages (Diplodactylidae, Pygopodidae and Carphodactylidae) may be older than those in the Gekkonidae.2. Phylogenetic relationships of the gekkonid lizardsThe Gekkonidae was the most heterogeneous and unwieldy of all gekkotan lizards. Samples representing 28 genera were collected , and 378 bp C-mos partial and 1459 bp 12S rRNA complete sequences were obtained. Two data sets were combined in the analysis.(1) Majority-role consensus phylogenetic trees cluster the taxa sampled into 6 clades:1) (Rhoptropus + Pachydaclylu\} Phelsumu;2) Nactus + Lygodactylus; 3 ) Christinus + Afrogecko -,4) Phyllodactylus (Hemiphyllodactylns + Gehyra)\5) ((Sphaerodactylus + Plenopits) Narudasia} (Syrtodactylus + Calodactylodes );6 ) Hemidactylus + Lepidodaclylus + Gekko, and the results have many defferences with those of Kluge (1987) and Russell (1972, 1976) based on morphological characters.(2) The result from combind data sets of C-mos and 12S rRNA gene sequences indicates Sphaerodactylus has a close relationship to Ptenopus and Narudasia, but it is in the basal position of gekkonids based on C-mos data alone. The higher order status of the sphaerodactyls will require more intensive sampling of this group.(3) As Teratoscincus dose not cluster with any other taxa with bootstrap supports inboth data sets, so the phylogenetic status of Teratoscincinae has not been resolved in the present study.3. The mitochondria! genome oftokayAnalyses of complete mitochondria! genomes provide not only information about structural arrangements which may serve as genomic evolutional marker but also sequ...