PHENOTYPIC PLASTICITY, SPECIATION, AND PHYLOGENY IN EARLY DANIAN PLANKTIC FORAMINIFERA

Abstract

Research Article| April 01, 2014 PHENOTYPIC PLASTICITY, SPECIATION, AND PHYLOGENY IN EARLY DANIAN PLANKTIC FORAMINIFERA Eduardo A. M. Koutsoukos Eduardo A. M. Koutsoukos Geologie-Paläontologie Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 234, DE-69120 Heidelberg, Germany. E-mail: ekoutsoukos@gmail.com Search for other works by this author on: GSW Google Scholar Author and Article Information Eduardo A. M. Koutsoukos Geologie-Paläontologie Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 234, DE-69120 Heidelberg, Germany. E-mail: ekoutsoukos@gmail.com Publisher: Cushman Foundation for Foraminiferal Research Received: 20 Mar 2013 Accepted: 10 Dec 2013 First Online: 13 Jul 2017 Online ISSN: 1943-264X Print ISSN: 0096-1191 © 2014 Cushman Foundation for Foraminiferal Research Journal of Foraminiferal Research (2014) 44 (2): 109–142. https://doi.org/10.2113/gsjfr.44.2.109 Article history Received: 20 Mar 2013 Accepted: 10 Dec 2013 First Online: 13 Jul 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Eduardo A. M. Koutsoukos; PHENOTYPIC PLASTICITY, SPECIATION, AND PHYLOGENY IN EARLY DANIAN PLANKTIC FORAMINIFERA. Journal of Foraminiferal Research 2014;; 44 (2): 109–142. doi: https://doi.org/10.2113/gsjfr.44.2.109 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Foraminiferal Research Search Advanced Search Abstract A piston core drilled at a water depth of 2809 m off Rio de Janeiro, southeastern Brazil, recovered a 1.83-m thick section of unconsolidated muddy sediments, representing a complete stratigraphic succession across the Cretaceous–Paleogene (K/Pg) boundary. The sediments yielded abundant, strikingly pristine tests of planktic and benthic foraminifera, unaffected by diagenetic alteration or recrystallization.The sedimentary record ranges from the uppermost Maastrichtian (P. hantkeninoides Zone) to the lower Danian (zones P0–P1c), spanning a time interval of about 3–4 Myr through the K/Pg transition. A detailed taxonomic appraisal of the recovered planktic foraminiferal assemblages is presented, together with an evaluation of lineage relationships, phylogenetic trends, and the sequence of evolutionary events that took place among the Globigerinina at the beginning of the Cenozoic.The numerous recent taxonomic studies of Danian planktic foraminifera notwithstanding, the significance of phenotypic varieties has never been assessed in a paleoecological context. Whereas the cancellate-walled, low trochospiral, large-sized Praemurica (Truncorotaloididae) and Parasubbotina and Subbotina (Globigerinidae) lineages evidently underwent rapid speciation over a relatively narrow phenotypic range, the small-sized Praemurica, the distinctly elevated trochoid Eoglobigerina (Globigerinidae), the Parvulorugoglobigerina, and the coiled to elongate morphotypes of the Guembelitria and Woodringina (all members of the family Guembelitriidae) and Chiloguembelina (Chiloguembelinidae) lineages show phenotypic plasticity over a much broader range. This dichotomy correlates with inferred differences in life-history parameters among these planktic taxa, including pelagic-dwelling preferences, related to reproductive and feeding strategies and to water-mass trophic levels.Two new early Danian planktic foraminiferal species are established herein: Praemurica nikolasi n. sp., the earliest recorded Truncorotaloididae and cancellate species, likely evolved directly from Hedbergella monmouthensis near the base of Zone P0 and probably giving rise to all subsequent cancellate lineages of the early Danian; and Globoconusa victori n. sp., evolved from Globoconusa daubjergensis within Zone P1c. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.