Instituto de Estudos Costeiros, Universidade Federal do Pará, Bragança, Pará, Brazil.
Museu Paraense Emílio Goeldi, Belém, Pará, Brazil.
Mol Phylogenet Evol. 2018 Sep;126:314-320. doi: 10.1016/j.ympev.2018.04.017. Epub 2018 Apr 12.
Lepidothrix is the most diverse genus of the family Pipridae, with eight recognized species. Although the genus' monophyly has been supported by both molecular and morphological characters, phylogenetic relationships and species limits within Lepidothrix remain uncertain. In the present study, we combined molecular sequences of mitochondrial (ND2 and COI) and nuclear (MYO, G3PDh and I5BF) markers in a multilocus analysis, to evaluate relationships and inter-specific limits among L. iris, L. nattereri, and L. vilasboasi, which are known to hybridize in eastern Amazonia. The results revealed a complex pattern, whereby events of secondary contact and gene flow after isolation and genetic and phenotypic differentiation prevented the recuperation of reciprocal monophyly among the studied taxa. The mitochondrial data indicate that L. nattereri is divided into two non-sister groups, one monophyletic, and the other, paraphyletic, with L. iris iris being more closely related to one of the two L. nattereri groups, while L. iris eucephala forms an undifferentiated clade with L. vilasboasi, probably resulting from an extensive process of mitochondrial introgression. In agreement with a previous study based on Single Nucleotide Polymorphism (SNP) data, mitochondrial haplotype networks also support that L. vilasboasi does not represent a recent "hybrid swarm" between L. iris and L. nattereri, but instead a genetically divergent lineage with a separate species status. Finally, the sister relationship recovered herein between L. iris iris and some western populations of L. nattereri currently in allopatry is also apparently explained by mitochondrial introgression, as also supported for nuclear genes by SNP data, indicating a complex scenario of past contact and gene flow between currently geographically distant Lepidothrix lineages.
鳞胸鹪鹛是管鼻鹱科中最多样化的属，有 8 个公认的物种。尽管该属的单系性得到了分子和形态特征的支持，但鳞胸鹪鹛属内的系统发育关系和种间界限仍不确定。在本研究中，我们结合了线粒体（ND2 和 COI）和核（MYO、G3PDh 和 I5BF）标记的分子序列，进行了多基因座分析，以评估已知在东亚马逊地区杂交的虹膜鳞胸鹪鹛、纳氏鳞胸鹪鹛和比氏鳞胸鹪鹛之间的关系和种间界限。结果显示出一种复杂的模式，即隔离后的次生接触和基因流事件，以及遗传和表型分化，阻止了所研究分类群之间互惠单系性的恢复。线粒体数据表明，纳氏鳞胸鹪鹛分为两个非姐妹群，一个单系群，另一个并系群，虹膜鳞胸鹪鹛与纳氏鳞胸鹪鹛的两个群之一关系更为密切，而虹膜鳞胸鹪鹛eucephala与比氏鳞胸鹪鹛形成一个不分枝的分支，可能是由于广泛的线粒体渗入。与先前基于单核苷酸多态性（SNP）数据的研究一致，线粒体单倍型网络也支持比氏鳞胸鹪鹛不是虹膜鳞胸鹪鹛和纳氏鳞胸鹪鹛之间最近的“杂交群”，而是一个具有独立物种地位的遗传分化谱系。最后，本文恢复的虹膜鳞胸鹪鹛 iris 与目前处于地理隔离的纳氏鳞胸鹪鹛西部一些种群之间的姐妹关系也显然是由线粒体渗入造成的，核基因的 SNP 数据也支持这一点，表明目前地理上遥远的鳞胸鹪鹛谱系之间存在过去接触和基因流的复杂情况。
