Phylogenomics supports Panpulmonata: Opisthobranch paraphyly and key evolutionary steps in a major radiation of gastropod molluscs
Phylogenomics supports Panpulmonata: Opisthobranch paraphyly and key evolutionary steps in a major radiation of gastropod molluscs
复制标题
DOI：
10.1016/j.ympev.2013.07.001
复制
发表时间：
2013-12-01
影响因子：
4.1
通讯作者：
Krug, Patrick J.
中科院分区：
文献类型：
--
作者：
Kocot, Kevin M.;Halanych, Kenneth M.;Krug, Patrick J.
肺动物有超过 30,000 种已描述的物种，是节肢动物门以外辐射范围最大的非海洋动物。肺是一项关键的进化创新，使陆生和淡水蜗牛和蛞蝓得以多样化。然而，最近的研究得出了关于肺单系的相互矛盾的结论，并且缺乏对姐妹群的支持，这阻碍了我们对这种主要动物辐射的理解。对线粒体蛋白编码基因的分析恢复了并系肺动物，其分级为单系后鳃动物，这是一种传统的海蛞蝓类群，长期以来被认为是肺动物的姐妹。相反，对核 rDNA 主导的数据集的分析表明后鳃亚目与肺亚目是并系群。目前还没有研究解决两个关键类群的位置问题：Sacoglossa（一种包括光合海蛞蝓的后鳃类群）和 Siphonarioidea（传统上生活在 Pulmonata 中的潮间带帽贝状蜗牛）。为了研究肺辐射基础上的进化关系，我们对 19 种腹足动物的 102 个核蛋白编码基因区域进行了系统发育分析。后鳃亚纲被发现与 Panpulmonata 是并系系，在这个分支中，Sacoglossa 是 Pulmonata 的姐妹，而 Siphonarioidea 是基础肺动物谱系。管虫与带壳的sacoglossans具有相似的鳃结构，但缺乏肺动物的收缩性气口，这表明它们是从促进肺动物辐射到非海洋栖息地的进化中间体进化而来的。 (C) 2013 Elsevier Inc. 保留所有权利。
Pulmonates, with over 30,000 described species, represent the largest radiation of non-marine animals outside of Arthropoda. The pulmonate lung was a key evolutionary innovation enabling diversification of terrestrial and freshwater snails and slugs. However, recent studies drew conflicting conclusions about pulmonate monophyly, and support for a sister group is lacking, hindering our understanding of this major animal radiation. Analyses of mitochondrial protein-coding genes recovered a paraphyletic Pulmonata grading into a monophyletic Opisthobranchia, a traditional group of sea slugs long considered sister to pulmonates. Conversely, analyses of datsets dominated by nuclear rDNA indicated Opisthobranchia is paraphyletic with respect to Pulmonata. No study resolved the placement of two key taxa: Sacoglossa, an opisthobranch group including photosynthetic sea slugs, and Siphonarioidea, intertidal limpet-like snails traditionally in Pulmonata. To examine evolutionary relationships at the base of the pulmonate radiation, we performed a phylogenomic analysis of 102 nuclear protein-coding gene regions for 19 gastropods. Opisthobranchia was recovered as paraphyletic with respect to Panpulmonata, a clade in which Sacoglossa was sister to Pulmonata, with Siphonarioidea as the basal pulmonate lineage. Siphonarioideans share a similar gill structure with shelled sacoglossans but lack the contractile pneumostome of pulmonates, suggesting descent from an evolutionary intermediate that facilitated the pulmonate radiation into non-marine habitats. (C) 2013 Elsevier Inc. All rights reserved.