Le Minh, Raxworthy Christopher J, McCord William P, Mertz Lisa
Department of Herpetology, Division of Vertebrate Zoology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA.
Mol Phylogenet Evol. 2006 Aug;40(2):517-31. doi: 10.1016/j.ympev.2006.03.003. Epub 2006 May 5.
Although tortoises of the family Testudinidae represent a familiar and widely distributed group of turtles, their phylogenetic relationships have remained contentious. In this study, we included 32 testudinid species (all genera and subgenera, and all species of Geochelone, representing 65% of the total familial species diversity), and both mitochondrial (12S rRNA, 16S rRNA, and cytb) and nuclear (Cmos and Rag2) DNA data with a total of 3387 aligned characters. Using diverse phylogenetic methods (Maximum Parsimony, Maximum Likelihood, and Bayesian Analysis) congruent support is found for a well-resolved phylogeny. The most basal testudinid lineage includes a novel sister relationship between Asian Manouria and North American Gopherus. In addition, this phylogeny supports two other major testudinid clades: Indotestudo+Malacochersus+Testudo; and a diverse clade including Pyxis, Aldabrachelys, Homopus, Chersina, Psammobates, Kinixys, and Geochelone. However, we find Geochelone rampantly polyphyletic, with species distributed in at least four independent clades. Biogeographic analysis based on this phylogeny is consistent with an Asian origin for the family (as supported by the fossil record), but rejects the long-standing hypothesis of South American tortoises originating in North America. By contrast, and of special significance, our results support Africa as the ancestral continental area for all testudinids except Manouria and Gopherus. Based on our systematic findings, we also propose modifications concerning Testudinidae taxonomy.
尽管陆龟科的陆龟是一类为人熟知且分布广泛的龟类，但它们的系统发育关系一直存在争议。在本研究中，我们纳入了32种陆龟科物种（所有属和亚属，以及陆龟属的所有物种，占该科物种多样性总量的65%），并使用了线粒体（12S rRNA、16S rRNA和细胞色素b）和核（Cmos和Rag2）DNA数据，共计3387个比对字符。使用多种系统发育方法（最大简约法、最大似然法和贝叶斯分析），我们发现了一个解析良好的系统发育树的一致支持。最基部的陆龟科谱系包括亚洲凹甲陆龟和北美地鼠龟之间一种新的姐妹关系。此外，这个系统发育树支持另外两个主要的陆龟科分支：印度陆龟+蛛网陆龟+欧陆陆龟；以及一个多样化的分支，包括蛛网龟属、阿尔达布拉象龟属、挺胸龟属、南非星丛龟属、岩陆龟属、饼干龟属、折背龟属和陆龟属。然而，我们发现陆龟属具有高度的多系性，其物种分布在至少四个独立的分支中。基于这个系统发育树的生物地理学分析与该科起源于亚洲的观点一致（化石记录也支持这一点），但拒绝了南美陆龟起源于北美的长期假说。相比之下，特别重要的是，我们的结果支持非洲是除凹甲陆龟和地鼠龟之外所有陆龟科动物的祖先大陆区域。基于我们的系统学发现，我们还对陆龟科分类法提出了修改建议。
