Centro Nacional Patagónico, Consejo Nacional de Investigaciones Científicas y Técnicas, Boulevard Almirante Brown 2915, ZC: U9120ACF, Puerto Madryn, Chubut, Argentina.
Mol Phylogenet Evol. 2011 Nov;61(2):381-91. doi: 10.1016/j.ympev.2011.07.006. Epub 2011 Jul 21.
The lizard genus Liolaemus is endemic to temperate South America and includes more than 225 species. Liolaemus gracilis and L. bibronii are closely related species that have large and overlapping geographic distributions, and the objective of this work is to further investigate the L. bibronii-L. gracilis mtDNA paraphyletic pattern previously detected, using an integrative approach, based on mtDNA, nuclear DNA and morphological characters. We identified eight morphological L. bibronii introgressed with L. gracilis mtDNAs, and the reciprocal for one L. gracilis, from six localities in the region of sympatry overlap. The morphological identity of these introgressed individuals was confirmed by diagnostic nuclear markers, and this represents the first well-documented case of interspecific hybridization in the lizard genus Liolaemus. Of the three most likely hypotheses for these observed patterns, we suggest that asymmetrical mtDNA introgression as a result of recent or ongoing hybridization between L. bibronii and L. gracilis is the most likely. This may be due to size selection by L. gracilis female preference for the larger L. bibroni males in sympatry, but this requires experimental confirmation.
蜥蜴属 Liolaemus 是温带南美洲的特有物种，包括超过 225 种。Liolaemus gracilis 和 L. bibronii 是密切相关的物种，它们的地理分布范围广泛且重叠，本研究的目的是通过整合 mtDNA、核 DNA 和形态特征的方法，进一步研究先前检测到的 L. bibronii-L. gracilis mtDNA 并系模式。我们从重叠分布区的六个地点鉴定出了 8 个具有 L. gracilis mtDNA 渗入的形态学上的 L. bibronii 个体，以及一个具有 L. gracilis mtDNA 渗入的形态学上的 L. bibronii 个体。这些渗入个体的形态同一性通过诊断性核标记得到了确认，这代表了 Liolaemus 蜥蜴属中首例有充分记录的种间杂交事件。对于这些观察到的模式的三个最可能的假说，我们认为，由于 L. bibronii 和 L. gracilis 之间最近或正在进行的杂交导致的不对称 mtDNA 渗入是最有可能的。这可能是由于 L. gracilis 雌性偏爱在同域中体型较大的 L. bibroni 雄性而导致的大小选择，但这需要实验证实。
