Congruence and indifference between two molecular markers for understanding oral evolution in the Marynidae sensu lato (Ciliophora, Colpodea).
Bottom Line: Our understanding of the evolution of oral structures within the Colpodida is confounded by the low number of morphological characters that can be used in constructing hypotheses, and by the low taxon and character sampling in molecular phylogenetic analyses designed to assess these hypotheses.We show that the inferred mitochondrial and nuclear SSU-rDNA trees, as well as concatenated and constrained analyses, are congruent in not recovering a monophyletic Marynidae.However, due to low node support, the trees are indifferent to whether the morphological characters used to unite the Marynidae are the result of retention of ancestral states or convergence.
Affiliation: Department of Ecology, University of Kaiserslautern, Germany. email@example.comShow MeSH
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Mentions: To evaluate the possibility of low taxon sampling affecting the inferred tree, taxon inclusion for nSSU-rDNA was limited to match the alignment for mtSSU-rDNA. This nuclear alignment of 1676 included characters resulted in identical ML and Bayesian topologies for moderately to highly supported nodes (Fig. 2). For non-Marynidae sequences, the nSSU-rDNA topology is congruent with previously published trees (Bourland et al. 2011; Dunthorn et al. 2008, 2009, 2011; Foissner et al. 2011; Quintela-Alonso et al. 2011) for moderately to highly supported nodes. Thus, the limited taxon inclusion does not appear to have an effect. As in the mtSSU-rDNA tree, the Marynidae s.l. are not monophyletic. Ilsiella branches sister to all Colpodida, except Bardeliella. The two Maryna sequences, which are sister to each other with full node support (100/100), form a clade with Hausmanniella and Colpoda aspera, although the node for this larger clade is not supported (<50/71). As the intervening nodes between Maryna and Ilsiella are not moderately to fully supported, the nSSU-rDNA tree provides little confidence in the non-monophyly of the Marynidae.
Affiliation: Department of Ecology, University of Kaiserslautern, Germany. firstname.lastname@example.org