10.1371/journal.pone.0128108 Silvia Spezzaferri Silvia Spezzaferri Michal Kucera Michal Kucera Paul Nicholas Pearson Paul Nicholas Pearson Bridget Susan Wade Bridget Susan Wade Sacha Rappo Sacha Rappo Christopher Robert Poole Christopher Robert Poole Raphaël Morard Raphaël Morard Claudio Stalder Claudio Stalder Fossil and Genetic Evidence for the Polyphyletic Nature of the Planktonic Foraminifera "<i>Globigerinoides</i>", and Description of the New Genus <i>Trilobatus</i> Public Library of Science 2015 New Genus Trilobatus Planktonic foraminifera ruber group clusters ruber group trilobus group type species Globigerina triloba Reuss genus Globigerinoides ruber clade sister taxon 2015-05-28 04:12:08 Dataset https://plos.figshare.com/articles/dataset/Fossil_and_Genetic_Evidence_for_the_Polyphyletic_Nature_of_the_Planktonic_Foraminifera_Globigerinoides_and_Description_of_the_New_Genus_Trilobatus_/1429569 <div><p>Planktonic foraminifera are one of the most abundant and diverse protists in the oceans. Their utility as paleo proxies requires rigorous taxonomy and comparison with living and genetically related counterparts. We merge genetic and fossil evidence of “<i>Globigerinoides</i>”, characterized by supplementary apertures on spiral side, in a new approach to trace their “total evidence phylogeny” since their first appearance in the latest Paleogene. Combined fossil and molecular genetic data indicate that this genus, as traditionally understood, is polyphyletic. Both datasets indicate the existence of two distinct lineages that evolved independently. One group includes “<i>Globigerinoides</i>” <i>trilobus</i> and its descendants, the extant <i>“Globigerinoides</i>” <i>sacculifer</i>, <i>Orbulina universa</i> and <i>Sphaeroidinella dehiscens</i>. The second group includes the <i>Globigerinoides ruber</i> clade with the extant <i>G</i>. <i>conglobatus</i> and <i>G</i>. <i>elongatus</i> and ancestors. In molecular phylogenies, the <i>trilobus</i> group is not the sister taxon of the <i>ruber</i> group. The <i>ruber</i> group clusters consistently together with the modern <i>Globoturborotalita rubescens</i> as a sister taxon. The re-analysis of the fossil record indicates that the first “<i>Globigerinoides</i>” in the late Oligocene are ancestral to the <i>trilobus</i> group, whereas the <i>ruber</i> group first appeared at the base of the Miocene with representatives distinct from the <i>trilobus</i> group. Therefore, polyphyly of the genus "<i>Globigerinoides</i>" as currently defined can only be avoided either by broadening the genus concept to include <i>G</i>. <i>rubescens</i> and a large number of fossil species without supplementary apertures, or if the <i>trilobus</i> group is assigned to a separate genus. Since the former is not feasible due to the lack of a clear diagnosis for such a broad genus, we erect a new genus <i>Trilobatus</i> for the <i>trilobus</i> group (type species <i>Globigerina triloba</i> Reuss) and amend <i>Globoturborotalita</i> and <i>Globigerinoides</i> to clarify morphology and wall textures of these genera. In the new concept, <i>Trilobatus</i> n. gen. is paraphyletic and gave rise to the <i>Praeorbulina</i> / <i>Orbulina</i> and <i>Sphaeroidinellopsis</i> / <i>Sphaeroidinella</i> lineages.</p></div>