Rodríguez-Flores P C, Macpherson E, Schnabel K E, Ahyong S T, Corbari L, Machordom A
Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, 26 Oxford St., Cambridge, MA 02138, USA; Centre d'Estudis Avançats de Blanes (CEAB-CSIC), C. acc. Cala Sant Francesc 14, 17300 Blanes, Girona, Spain; Museo Nacional de Ciencias Naturales (MNCN-CSIC), José Gutiérrez Abascal, 2, 28006 Madrid, Spain.
Centre d'Estudis Avançats de Blanes (CEAB-CSIC), C. acc. Cala Sant Francesc 14, 17300 Blanes, Girona, Spain.
Mol Phylogenet Evol. 2022 Jun;171:107467. doi: 10.1016/j.ympev.2022.107467. Epub 2022 Mar 26.
The exceptional hidden diversity included in the squat lobster genus Phylladiorhynchus and its wide bathymetric and geographic range make it an interesting group to thoroughly study its evolutionary history. Here we have analyzed the entire currently known species diversity of Phylladiorhynchus using an integrative approach that includes morphological and molecular characters. The aim was to establish whether depth range (bathymetry) has played a role in their morphological and molecular evolution and in their diversification pathways. Phylogenetic analyses recovered the genus as monophyletic and as the sister group of Coralliogalathea, conforming with current systematic hypotheses, although their placement in a monophyletic Galatheidae is doubted. All the analyzed species represent well-supported lineages, structured in ten clades, correlated in most part with the morphological phylogeny. The reconstruction of ancestral habitat showed that the most recent common ancestor of Phylladiorhynchus most likely lived in shallow water environments. The divergence time estimation analyses dated the origin of the genus back to the Upper Jurassic, preceding the origin of all the other galatheoid lineages. Morphological analyses suggested that species from deeper waters exhibit greater morphological divergences and lower genetic divergences in comparison to species from shallower waters. In Phylladiorhynchus, the colonization of deeper waters has taken place independently multiple times since the Lower-Cretaceous. Our reconstruction of ancestral habitat suggests that shallow water ancestors might show an acceleration in the molecular rate of evolution and a slowdown in the rates of morphological evolution in comparison to deep sea lineages. However, although lineages from shallow and deep sea habitats show slight differences in diversification trends, bathymetry does not significantly affect the diversification rate in Phylladiorhynchus according to our diversification analyses.
蹲龙虾属Phylladiorhynchus所包含的特殊隐藏多样性及其广泛的水深分布和地理范围，使其成为一个研究其进化历史的有趣类群。在此，我们采用了一种综合方法，包括形态学和分子特征，对Phylladiorhynchus目前已知的全部物种多样性进行了分析。目的是确定深度范围（水深）是否在其形态和分子进化以及多样化途径中发挥了作用。系统发育分析表明该属为单系群，是珊瑚螯虾属的姐妹群，这与当前的系统假说一致，尽管它们在单系的铠甲虾科中的位置仍受到质疑。所有分析的物种都代表了得到充分支持的谱系，分为十个分支，在很大程度上与形态系统发育相关。祖先栖息地的重建表明，Phylladiorhynchus最近的共同祖先很可能生活在浅水环境中。分歧时间估计分析将该属的起源追溯到上侏罗纪，早于所有其他铠甲虾类谱系的起源。形态学分析表明，与来自较浅水域的物种相比，来自较深水域的物种表现出更大的形态差异和更低的遗传差异。在Phylladiorhynchus中，自下白垩纪以来，深水栖息地的定殖已经独立发生了多次。我们对祖先栖息地的重建表明，与深海谱系相比，浅水祖先可能在分子进化速率上加快，而在形态进化速率上减缓。然而，尽管来自浅海和深海栖息地的谱系在多样化趋势上存在细微差异，但根据我们的多样化分析，水深对Phylladiorhynchus的多样化速率没有显著影响。
