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许多东亚和北美的生物类群之间呈现较近的亲缘关系，格雷分布即指这种生物洲际间断分布的现象．本文通过线粒体DNA （mtDNA）12S rRNA基因序列分析，证明北美的滑蜥属Scincella （Squamata：Scincidae）物种Sc．late-ralis与中国的滑蜥属南滑蜥种组呈现典型的格雷分布．南滑蜥种组包括宁波滑蜥Sc．modesta，秦岭滑蜥Sc．tsinlin-gensis，南滑蜥Sc．reevesii，和一个采自广东鼎湖山自然保护区的未命名种Scincella indet．．这个鼎湖山未命名种并不具备滑蜥属所特有的鉴别性特征“睑窗”，但显示它与Sc．modesta，Sc．tsinlingensis都是由Sc．reevesii演化而来的近缘种．证实了之前认为亚洲的蜓蜥属Sphenomorphus与滑蜥属Scincella是复系的观点，目前美洲物种Sp．cherriei应隶属于滑蜥属Scincella，具睑窗或不具睑窗的物种分别出现在系统树的不同分支中．研究结果支持前人将Kaestlea tra-vancorica从滑蜥属中划分出去的观点．根据分子钟估算，北美的滑蜥从它们的中国祖先分化出来的时间可追溯到第三纪中新世，约7.3-21.6百万年前，当时白令陆桥还露出海平面而且气候湿润．该研究为洲际分布的物种的系统发育和生物地理研究提供了理论依据．“,”Grayian distribution denotes the biological similarities between southeastern North America and East Asia .Using 12S rRNA gene sequences of mitochondrial DNA , we present evidence that the North American ground skinks in Scincella (Squamata:Scincidae), Sc.lateralis and relatives, exhibit classic Grayian distribution, emerging genetically from within the Chinese group of Scincella that includes Sc.modesta and Sc.tsinlingensis;all derivatives from Chinese Sc.reevesii.A su-perficially similar undescribed species , as yet known only from Dinghushan , Guangdong Province , China, also arises within this group but lacks the lower eyelid “spectacle” usually thought diagnostic of the genus Scincella.Our molecular analyses confirm previous work indicating that Asian Sphenomorphus is paraphyletic with respect to Scincella, confirm that the Ameri-can Scincella include “Sphenomorphus” cherriei, necessitating that the spectacle scale has been independently either devel-oped or lost in separate lineages of Scincidae , and provide further evidence for the separation of Kaestlea travancorica from Scincella.The separation time of North American Scincella from their Chinese congeners dates from the Miocene in Tertiary about 7.3-21.6 million years ago when Beringia was extant and mesic .Our studies contribute further to phylogenetics and biogeography of Scincella from North America and China and call for further international collaboration on resolution of taxo -nomic problems among lygosomine species .