title: Exceptionally preserved 450-million-year-old ordovician ostracods with brood care.
abstract: Ostracod crustaceans are the most abundant fossil arthropods and are characterized by a long stratigraphic range. However, their soft parts are very rarely preserved, and the presence of ostracods in rocks older than the Silurian period [1-5] was hitherto based on the occurrence of their supposed shells. Pyritized ostracods that preserve limbs and in situ embryos, including an egg within an ovary and possible hatched individuals, are here described from rocks of the Upper Ordovician Katian Stage Lorraine Group of New York State, including examples from the famous Beecher's Trilobite Bed [6, 7]. This discovery extends our knowledge of the paleobiology of ostracods by some 25 million years and provides the first unequivocal demonstration of ostracods in the Ordovician period, including the oldest known myodocope, Luprisca incuba gen. et sp. nov. It also provides conclusive evidence of a developmental brood-care strategy conserved within Ostracoda for at least 450 million years.
authors.affiliation: Department of Geology, University of Leicester, Leicester LE1 7RH, UK. Electronic address: djs@leicester.ac.uk.
authors.forename: David J
authors.initials: DJ
authors.lastname: Siveter
authors.affiliation: BioGeos Japan Agency of Marine Science and Technology, 2-15 Natsushima, Yokosuka City 237-0061, Kanagawa Prefecture, Japan.
authors.forename: Gengo
authors.initials: G
authors.lastname: Tanaka
authors.affiliation: Biodiversity Institute, University of Kansas, Lawrence, KS 66045-7593, USA.
authors.forename: Una C
authors.initials: UC
authors.lastname: Farrell
authors.affiliation: 371 Pawling Street, Watertown, NY 13601, USA.
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Martin
authors.affiliation: Earth Collections, University Museum of Natural History, Oxford OX1 3PW, UK; Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK.
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Siveter
authors.affiliation: Department of Geology & Geophysics and Yale Peabody Museum of Natural History, Yale University, P.O. Box 208109, New Haven, CT 06520-8109, USA.
authors.forename: Derek E G
authors.initials: DE
authors.lastname: Briggs
mesh_terms: D000818:Animals; D003445:Crustacea / Q000033:anatomy & histology / Q000502:physiology*; D005260:Female; D005580:Fossils; D009518:New York; D012098:Reproduction