DOCSLIB.ORG

From the Lower Devonian in Qujing, Yunnan, China

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
From the Lower Devonian in Qujing, Yunnan, China Historical Biology An International Journal of Paleobiology ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/ghbi20 Falxcornus, a new genus of Tridensaspidae (Galeaspida, stem-Gnathostomata) from the Lower Devonian in Qujing, Yunnan, China Xinyuan Meng & Zhikun Gai To cite this article: Xinyuan Meng & Zhikun Gai (2021): Falxcornus, a new genus of Tridensaspidae (Galeaspida, stem-Gnathostomata) from the Lower Devonian in Qujing, Yunnan, China, Historical Biology, DOI: 10.1080/08912963.2021.1952198 To link to this article: https://doi.org/10.1080/08912963.2021.1952198 Published online: 27 Jul 2021. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=ghbi20 HISTORICAL BIOLOGY https://doi.org/10.1080/08912963.2021.1952198 Falxcornus, a new genus of Tridensaspidae (Galeaspida, stem-Gnathostomata) from the Lower Devonian in Qujing, Yunnan, China Xinyuan Menga,b and Zhikun Gaia,b,c aInstitute of Vertebrate Palaeontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China; bUniversity of the Chinese Academy of Sciences, Beijing, China; cCAS Center for Excellence in Life and Paleoenvironment, Beijing, China ABSTRACT ARTICLE HISTORY A new genus and species of galeaspid, Falxcornus liui gen. et sp. nov., is described from the Xishancun Received 25 April 2021 Formation (Lochkovian, Lower Devonian) in Qujing, Yunnan, China. The new taxon displays a suite of Accepted 27 June 2021 diagnostic characters of the Eugaleaspiformes and strikingly resembles the tridensaspids Tridensaspis and KEYWORDS Pterogonaspis in its sickle-like complex of cornual and inner cornual processes, leaf-like inner cornual Falxcornus; Lower Devonian; processes, and median dorsal opening posteriorly placed level with the centre of the orbital opening, but Galeaspida; Tridensaspidae; clearly differs from these genera in lacking the rostral process and laterally projecting cornual processes. An taxonomy; vertebrate extended phylogenetic analysis of the Galeaspida suggests that Falxcornus, Pterogonaspis and Tridensaspis palaeontology form a monophyletic group as the family Tridensaspidae, and Falxcornus is resolved as sister to Pterogonaspis and Tridensaspis. Therefore, Falxcornus liui gen. et sp. nov. now represents the most primitive and oldest known tridensaspid fish. Its subacute rostral margin and sickle-like complex of cornual and inner cornual processes likely represent an intermediate state of these highly specialised rostral and lateral projecting processes, respectively. The recurrent evolution of similar cephalic elaborations within the Galeaspida suggests that some galeaspids could manipulate water flow around their headshields to become active animals with higher manoeuvrability and versatility, similar to osteostracans. Introduction the Tridensaspidae by Shan et al. (2020), as it formed a monophyletic group together with Tridensaspis magnoculus in The Galeaspida isa clade of armoured jawless ‘ostracoderms’ (stem- all parsimony-based cladograms (Zhu 1992; Gai et al. 2005; Zhu gnathostomes) restricted to East Asia during the Middle and Gai 2006; Shan et al. 2020; Jiang et al. 2021). Ferrón et al. Palaeozoic (Tarlo 1967; Zhu 1992; Janvier 1996, 2009; Zhu and (2020,2021) showed that these cephalic elaborations of headshields Gai 2006; Gai et al. 2018; Shan et al. 2020; Jiang et al. 2021). They represent adaptations for passive hydrodynamic control both in the are among the enigmatic clades of stem-gnathostomes key to osteostracans and galeaspids. Therefore, the Tridensaspidae is an understanding the transition from jawless to jawed vertebrates important clade for understanding the last adaptive radiation of (Janvier 1996; Donoghue et al., 2000; Sansom et al., 2010; Gai galeaspids during the Pragian stage of the Early Devonian. et al., 2011; Gai and Zhu, 2012; Donoghue et al. 2014; Keating However, the evolution of cephalic elaborations within the and Donoghue 2016; Gai et al., 2019). Research on ostracoderm Eugaleaspiformes remains enigmatic because there is no intermedi­ morphology and phylogeny could facilitate interpretation of the ate state of these highly specialised rostral and lateral projecting gradual assembly of gnathostome characters such as jaws, processes. This condition is considerably different from that of the a mineralised dermal skeleton, vertebrae, a mineralised braincase, Huananaspiformes. Here, we describe a new eugaleaspidiform paired nostrils, a differentiated gut, a complex inner ear, externally genus and species from the lower part of the Xishancun open endolymphatic ducts, and paired pectoral and pelvic appen­ Formation (lower Lochkovian, Lower Devonian). The new taxon dages (Donoghue et al. 2014; Keating and Donoghue 2016; Gai et al. is characterised by a subacute rostral margin and sickle-like com­ 2011). Among galeaspids, the family Tridensaspidae plex of cornual and inner cornual processes, which likely represent (Eugaleaspiformes) is of particular interest because their head­ an intermediate condition between Tridensaspis and Nochelaspis. shields exhibit significant convergence with those of the As the new taxon was collected from the lower Lochkovian, lower Huananaspiformes in possessing similar cephalic elaborations than the other members of the Tridensaspidae, it sheds new light on (elongated rostra, lateral expansions or processes), which were the early evolution of the Tridensaspidae. previously regarded as diagnostic characters of the Huananaspiformes (Janvier 1975). The Tridensaspidae was erected by Liu (1986) based on Tridensaspis magnoculus from the bottom of Anatomical abbreviations the Yukiang Formation (Pragian, Lower Devonian) of Guangxi, as br.f, branchial fossa; br.o, branchial opening; c, cornual process; da, the rostral process and lateral projecting processes of this taxon dorsal aorta; dcm, dorsal commissure; ic, inner cornual process; ifc, were unknown in all other members of the Eugaleaspiformes. infraorbital canal; ldc, lateral dorsal canal; ltc, lateral transverse Pterogonaspis yuhaii (Zhu 1992) from the Xujiachong Formation canal;md.o, median dorsal opening;mdc, median dorsal canal; (Pragian, Lower Devonian) of Qujing, Yunnan was later referred to obr.c, oralobranchial chamber; oesc,oesophagus; orb, orbital CONTACT Zhikun Gai [email protected] Institute of Vertebrate Palaeontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China; Institute of Vertebrate Palaeontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China; CAS Center for Excellence in Life and Paleoenvironment, Beijing, China; University of the Chinese Academy of Sciences, Beijing, China © 2021 Informa UK Limited, trading as Taylor & Francis Group Published online 27 Jul 2021 2 X. MENG AND Z. GAI opening; pi, pineal fossa; ro, rostral process; soc1, anterior supraor­ and Zhu 2010; Xue et al. 2018) (Figure 1(c)). The Xishancun bital canal; soc2, posterior supraorbital canal; pb.b, postbranchial Formation is mainly composed of hard and dense quartz sand­ bar; pb.w, postbranchial wall; vr, ventral rim. stone with yellowish green and black shale. A layer of greyish yellow fine-grained sandstone is in conformable or disconformable contact with the Silurian Yulongssu Formation at the bottom of Geological setting the Xishancun Formation, and the Xitun Formation conformably The material of Falxcornus liui gen. et sp. nov. was collected by overlies it (Lin et al. 1998; Ma et al. 2009). A large number of Professor Yuhai Liu in May 1980 under a water pipe on the south galeaspid, placoderm, sarcopterygian and actinopterygian fossils side of the road in front of the Qujing Maternal and Child Health have been found in the Xishancun Formation, and these constitute Care Hospital, Yunnan Province, China (Figure 1(a, b)). The an important early vertebrate fauna (Zhu et al. 2000; Zhao and Lower Devonian strata in eastern Yunnan Province are well devel­ Zhu 2010). Galeaspids described from the Xishancun Formation oped with a complete sequence, known as the Cuifengshan Group, include Eugaleaspis changi (Liu 1965, Liu 1980), Yunnanogaleaspis which is divided into four formations: the Xishancun, Xitun, major (Pan and Wang 1980), Nochelaspis maeandrine (Zhu 1992), Guijiatun and Xujiachong formations from bottom to top (Wang Polybranchiaspis liaojiaoshanensis (Liu 1965), P. minor, Laxaspis 1984; Zhu 1992; Liu 2002; Zhu and Gai 2006; Ma et al. 2009; Zhao qujingensis, L. yulongssus, Diandongaspis xishancunensis (Liu Figure 1. Maps of the fossil locality of Falxcornus liui gen. et sp. nov. (a, b) and the fossil fish-bearing lithological column (c) in Qujing, Yunnan Province, China. HISTORICAL BIOLOGY 3 1975), Pseudolaxaspis rostrata (Liu 1975; Gai et al. 2018), a subtriangular headshield with cornual and inner cornual processes, ‘Dongfangaspis qujingensis’ (Pan and Wang 1981), Damaspis var­ a longitudinal oval median dorsal opening, and a typical eugaleaspid- tus (Wang and Wang 1982), Nanpanaspis microculus (Liu 1965), type sensory canal system. It differs from the Shuyuidae, Altigibbaspis huiqingae (Liu et al. 2018), Siyingia perlatuspinosa (Si Sinogaleaspidae and Eugaleaspidae in its leaf-like inner cornual pro­ et al. 2015), Pentathyraspis pelta (Pan 1992) and Stephaspis dipter­ cess, differs from Shuyuidae and Sinogaleaspidae in its slit-like median iga (Gai and Zhu 2007). This
Load more

Recommended publications
  • Polskaakademianauk Instytutpaleobiologii
    POLSKA AKADEMIA NAUK INSTYTUT PALEOBIOLOGII im. Romana Kozłowskiego SILURIAN AND DEVONIAN HETEROSTRACI FROM POLAND AND HYDRODYNAMIC PERFORMANCE OF PSAMMOSTEIDS Sylurskie i dewońskie Heterostraci z Polski oraz efektywność hydrodynamiczna psammosteidów Marek Dec Dissertation for degree of doctor of Earth and related environmental sciences, presented at the Institute of Paleobiology of Polish Academy of Sciences Rozprawa doktorska wykonana w Instytucie Paleobiologii Polskiej Akademii Nauk pod kierunkiem prof. dr hab. Magdaleny Borsuk-Białynickiej w celu uzyskania stopnia doktora w dyscyplinie Nauki o Ziemi oraz środowisku Warszawa 2020 CONTENTS ACKNOWLEDGMENTS…………………………………………………………….….... 3 STRESZCZENIE………………………………………………………………….....….. 4 SUMMARY……………………………………………………………………….…….. 8 CHAPTER I…………………………………………………………………………….. 13 TRAQUAIRASPIDIDAE AND CYATHASPIDIDAE (HETEROSTRACI) FROM LOWER DEVONIAN OF POLAND CHAPTER II……………………………………………………………………….…… 24 A NEW TOLYPELEPIDID (AGNATHA, HETEROSTRACI) FROM THE LATE SILURIAN OF POLAND CHAPTER III…………………………………………………………………………... 41 REVISION OF THE EARLY DEVONIAN PSAMMOSTEIDS FROM THE “PLACODERM SANDSTONE” - IMPLICATIONS FOR THEIR BODY SHAPE RECONSTRUCTION CHAPTER IV……………………………………………………………………….….. 82 NEW MIDDLE DEVONIAN (GIVETIAN) PSAMMOSTEID FROM HOLY CROSS MOUNTAINS (POLAND) CHAPTER V……………………………………………………………………………109 HYDRODYNAMIC PERFORMANCE OF PSAMMOSTEIDS: NEW INSIGHTS FROM COMPUTATIONAL FLUID DYNAMICS SIMULATIONS 2 ACKNOWLEDGMENTS First and foremost I would like to say thank you to my supervisor Magdalena
    [Show full text]
  • UNIVERSITY of CALIFORNIA Los Angeles
    UNIVERSITY OF CALIFORNIA Los Angeles Evolution of the boxfish carapace: functional consequences of shape A thesis submitted in partial satisfaction of the requirements for the degree of Master of Science in Biology by Tina Ashley Marcroft 2015 ABSTRACT OF THE THESIS Evolution of the boxfish carapace: functional consequences of shape by Tina Ashley Marcroft Master of Science in Biology University of California, Los Angeles, 2015 Professor Michael Edward Alfaro, Chair Boxfishes are a group of heavily armored Tetraodontiform fishes that are highly variable in shape. Disparification of shape could be driven by a simple performance trade-off between its two hypothesized primary functions: protection from predation and maneuverability. Alternatively, disparification could be driven by many-to-one mapping of shape to performance, where a relaxation in morphological constraint where many of morphologies have the same performance. We tested this by isolating the major features of the boxfish carapace shape and tested for their correlation to performance, as well as for a negative correlation between performances. We found that some features were correlated but very weakly, and that the two performances did trade-off but also weakly. This weak correlation primarily suggests that many- to-one mapping of shape to performance is driving disparification, which was unobserved in continuous 3D shape systems until this study. ii The thesis of Tina Ashley Marcroft is approved. Blaire Van Valkenburgh David K. Jacobs Michael Edward Alfaro, Committee Chair University of California, Los Angeles 2015 iii I dedicate this thesis to Carrie Umetsu, Joseph Aprill, Mai Nguyen, Princess Gilbert, Francisca Wufu, Deb Pires, Jonathan Chang, Herbert Icasiano, and many others, without whose unwavering emotional and professional support I would not have completed this text.
    [Show full text]
  • Categorical Versus Geometric Morphometric Approaches To
    [Palaeontology, 2020, pp. 1–16] CATEGORICAL VERSUS GEOMETRIC MORPHOMETRIC APPROACHES TO CHARACTERIZING THE EVOLUTION OF MORPHOLOGICAL DISPARITY IN OSTEOSTRACI (VERTEBRATA, STEM GNATHOSTOMATA) by HUMBERTO G. FERRON 1,2* , JENNY M. GREENWOOD1, BRADLEY DELINE3,CARLOSMARTINEZ-PEREZ 1,2,HECTOR BOTELLA2, ROBERT S. SANSOM4,MARCELLORUTA5 and PHILIP C. J. DONOGHUE1,* 1School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK; [email protected], [email protected], [email protected] 2Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de Valencia, C/ Catedratic Jose Beltran Martınez 2, 46980, Paterna, Valencia, Spain; [email protected], [email protected] 3Department of Geosciences, University of West Georgia, Carrollton, GA 30118, USA; [email protected] 4School of Earth & Environmental Sciences, University of Manchester, Manchester, M13 9PT, UK; [email protected] 5School of Life Sciences, University of Lincoln, Riseholme Hall, Lincoln, LN2 2LG, UK; [email protected] *Corresponding authors Typescript received 2 October 2019; accepted in revised form 27 February 2020 Abstract: Morphological variation (disparity) is almost aspects of morphology. Phylomorphospaces reveal conver- invariably characterized by two non-mutually exclusive gence towards a generalized ‘horseshoe’-shaped cranial mor- approaches: (1) quantitatively, through geometric morpho- phology and two strong trends involving major groups of metrics;
    [Show full text]
  • Copyrighted Material
    06_250317 part1-3.qxd 12/13/05 7:32 PM Page 15 Phylum Chordata Chordates are placed in the superphylum Deuterostomia. The possible rela- tionships of the chordates and deuterostomes to other metazoans are dis- cussed in Halanych (2004). He restricts the taxon of deuterostomes to the chordates and their proposed immediate sister group, a taxon comprising the hemichordates, echinoderms, and the wormlike Xenoturbella. The phylum Chordata has been used by most recent workers to encompass members of the subphyla Urochordata (tunicates or sea-squirts), Cephalochordata (lancelets), and Craniata (fishes, amphibians, reptiles, birds, and mammals). The Cephalochordata and Craniata form a mono- phyletic group (e.g., Cameron et al., 2000; Halanych, 2004). Much disagree- ment exists concerning the interrelationships and classification of the Chordata, and the inclusion of the urochordates as sister to the cephalochor- dates and craniates is not as broadly held as the sister-group relationship of cephalochordates and craniates (Halanych, 2004). Many excitingCOPYRIGHTED fossil finds in recent years MATERIAL reveal what the first fishes may have looked like, and these finds push the fossil record of fishes back into the early Cambrian, far further back than previously known. There is still much difference of opinion on the phylogenetic position of these new Cambrian species, and many new discoveries and changes in early fish systematics may be expected over the next decade. As noted by Halanych (2004), D.-G. (D.) Shu and collaborators have discovered fossil ascidians (e.g., Cheungkongella), cephalochordate-like yunnanozoans (Haikouella and Yunnanozoon), and jaw- less craniates (Myllokunmingia, and its junior synonym Haikouichthys) over the 15 06_250317 part1-3.qxd 12/13/05 7:32 PM Page 16 16 Fishes of the World last few years that push the origins of these three major taxa at least into the Lower Cambrian (approximately 530–540 million years ago).
    [Show full text]
  • Devonian Jawless Vertebrates
    FULL COMMUNICATIONS PALAEONTOLOGY Phylogenetic relationships of psammosteid heterostracans (Pteraspidiformes), Devonian jawless vertebrates Vadim Glinskiy PALAEONTOLOGY Institute of Earth Sciences, Saint Petersburg State University, Universitetskaya nab., 7–9, Saint Petersburg, 199034, Russian Federation Address correspondence and requests for materials to Vadim Glinskiy, [email protected] Abstract Psammosteid heterostracans are a group (suborder Psammosteoidei) of Devo- nian-age jawless vertebrates, which is included in the order Pteraspidiformes. The whole group of psammosteids is represented by numerous species (more than 40); their phylogenetic relationships are still poorly known and deserve further study. Classical researchers of the psammosteids, such as D. Obruchev, E. Mark-Kurik and L. Halstead Tarlo, had different views on the phylogeny of the group (e.g. origins and evolution of Psammosteus). To check the modern hy- potheses of psammosteid origins from various Pteraspidiformes and to clarify psammosteid interrelationships, the most complete phylogeny of this group (38 ingroup taxa + juvenile Drepanapsis) is presented here. Different methods of data analysis were used to explore the psammosteid data set, including equally weighted characters versus implied weighting. According to the results of the phylogenetic analysis, the monophyletic status of the group and their early development from the Pteraspidiformes are supported. The diagnoses and interrelationships of many taxa are clarified. Two new genera are proposed (Vladimirolepis
    [Show full text]
  • Computational Fluid Dynamics Suggests Ecological Diversification
    Report Computational Fluid Dynamics Suggests Ecological Diversification among Stem-Gnathostomes Highlights Authors d Osteostracan headshield morphologies exhibit different Humberto G. Ferro´ n, hydrodynamic efficiencies Carlos Martı´nez-Perez, Imran A. Rahman, d Osteostracans had adaptations for passive control of water Vı´ctor Selles de Lucas, Hector Botella, flow around the body Philip C.J. Donoghue d Jawless stem-gnathostomes were ecologically diversified Correspondence d The origin of jaws was not the trigger for vertebrate ecological [email protected] (H.G.F.), diversification [email protected] (P.C.J.D.) In Brief Ferron et al. show, using computational fluid dynamics, that early jawless vertebrates were ecologically diversified and had complex hydrodynamic adaptations. These findings challenge the traditional scenario of jaws as the key evolutionary innovation that precipitated the ecological diversification of our ancestors. Ferro´ n et al., 2020, Current Biology 30, 1–6 December 7, 2020 ª 2020 Elsevier Inc. https://doi.org/10.1016/j.cub.2020.09.031 ll Please cite this article in press as: Ferro´ n et al., Computational Fluid Dynamics Suggests Ecological Diversification among Stem-Gnathostomes, Cur- rent Biology (2020), https://doi.org/10.1016/j.cub.2020.09.031 ll Report Computational Fluid Dynamics Suggests Ecological Diversification among Stem-Gnathostomes Humberto G. Ferro´ n,1,2,5,* Carlos Martı´nez-Perez, 1,2 Imran A. Rahman,3 Vı´ctor Selles de Lucas,4 Hector Botella,2 and Philip C.J. Donoghue1,* 1School of Earth
    [Show full text]
  • Hydrodynamic Performance of Psammosteids: New Insights from Computational Fluid Dynamics Simulations
    Editors' choice Hydrodynamic performance of psammosteids: New insights from computational fluid dynamics simulations MAREK DEC The shape of dermal armor protecting the body in the suggested that they fed on starfish which they picked up from Paleozoic agnathans such as the Heterostaci has an import- the sea floor (Patten 1932), but they have also been interpreted ant hydrodynamic role in providing lift or drag force gen- as mud grubbers living in shallow seas (Tarlo 1965). The wide eration. Here, by performing computational fluid dynamics and downwardly curved branchial plates of large psammoste- simulations (CFD), the measurements of hydrodynamic lift/ ids were considered to be a support while resting on soft bottom drag force and lift or drag coefficients were taken for two substrates (Janvier 1996). In addition to the supporting nature psammosteids Guerichosteus and Tartuosteus with refer- of the head shield, the tail fin of the psammosteid Drepanaspis ence to the pteraspid Errivaspis. This study shows the sub- gemuendenensis, which comprises the 1/4 of the total length stantially higher values of the lift coefficient and lift-to-drag of the body, is responsible for generating considerable propul- ratio for the psammosteids Guerichosteus and Tartuosteus sive force (Mark-Kurik 1992). These fishes, regardless of their compared with Errivaspis. The tendencies in the evolution of possible substrate-dwelling habits, were also capable of active dermal exoskeleton, especially the widening of the branchial swimming. plates of psammosteids was directed towards the increased A new reconstruction of Guerichosteus kozlowskii recently generation of lift force to provide efficient cruising. shed light on the body shape of this psammosteids (Dec 2019).
    [Show full text]
  • Hydrodynamics of Fossil Fishes
    Downloaded from rspb.royalsocietypublishing.org on September 18, 2014 Hydrodynamics of fossil fishes Thomas Fletcher, John Altringham, Jeffrey Peakall, Paul Wignall and Robert Dorrell Proc. R. Soc. B 2014 281, 20140703, published 18 June 2014 References This article cites 82 articles, 22 of which can be accessed free http://rspb.royalsocietypublishing.org/content/281/1788/20140703.full.html#ref-list-1 This article is free to access Subject collections Articles on similar topics can be found in the following collections biomechanics (87 articles) evolution (1887 articles) Receive free email alerts when new articles cite this article - sign up in the box at the top Email alerting service right-hand corner of the article or click here To subscribe to Proc. R. Soc. B go to: http://rspb.royalsocietypublishing.org/subscriptions Downloaded from rspb.royalsocietypublishing.org on September 18, 2014 Hydrodynamics of fossil fishes Thomas Fletcher1, John Altringham2, Jeffrey Peakall1, Paul Wignall1 and Robert Dorrell1 1School of Earth and Environment, and 2School of Biology, University of Leeds, Leeds, rspb.royalsocietypublishing.org West Yorkshire LS2 9JT, UK From their earliest origins, fishes have developed a suite of adaptations for loco- motion in water, which determine performance and ultimately fitness. Even without data from behaviour, soft tissue and extant relatives, it is possible to infer a wealth of palaeobiological and palaeoecological information. As in Review extant species, aspects of gross morphology such as streamlining, fin position and tail type are optimized even in the earliest fishes, indicating similar life Cite this article: Fletcher T, Altringham J, strategies have been present throughout their evolutionary history.
    [Show full text]
  • Hydrodynamics of Fossil Fishes
    Downloaded from rspb.royalsocietypublishing.org on June 19, 2014 Hydrodynamics of fossil fishes Thomas Fletcher, John Altringham, Jeffrey Peakall, Paul Wignall and Robert Dorrell Proc. R. Soc. B 2014 281, 20140703, published 18 June 2014 References This article cites 82 articles, 22 of which can be accessed free http://rspb.royalsocietypublishing.org/content/281/1788/20140703.full.html#ref-list-1 This article is free to access Receive free email alerts when new articles cite this article - sign up in the box at the top Email alerting service right-hand corner of the article or click here To subscribe to Proc. R. Soc. B go to: http://rspb.royalsocietypublishing.org/subscriptions Downloaded from rspb.royalsocietypublishing.org on June 19, 2014 Hydrodynamics of fossil fishes Thomas Fletcher1, John Altringham2, Jeffrey Peakall1, Paul Wignall1 and Robert Dorrell1 1School of Earth and Environment, and 2School of Biology, University of Leeds, Leeds, rspb.royalsocietypublishing.org West Yorkshire LS2 9JT, UK From their earliest origins, fishes have developed a suite of adaptations for loco- motion in water, which determine performance and ultimately fitness. Even without data from behaviour, soft tissue and extant relatives, it is possible to infer a wealth of palaeobiological and palaeoecological information. As in Review extant species, aspects of gross morphology such as streamlining, fin position and tail type are optimized even in the earliest fishes, indicating similar life Cite this article: Fletcher T, Altringham J, strategies have been present throughout their evolutionary history. As hydro- Peakall J, Wignall P, Dorrell R. 2014 dynamical studies become more sophisticated, increasingly complex fluid Hydrodynamics of fossil fishes.
    [Show full text]
  • Fishes of the World
    Fishes of the World Fishes of the World Fifth Edition Joseph S. Nelson Terry C. Grande Mark V. H. Wilson Cover image: Mark V. H. Wilson Cover design: Wiley This book is printed on acid-free paper. Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Published by John Wiley & Sons, Inc., Hoboken, New Jersey. Published simultaneously in Canada. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at www.wiley.com/go/permissions. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with the respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be createdor extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation.
    [Show full text]
  • A Redescription of Tesseraspis Mosaica Karatajūtė-Talimaa, 1983
    Acta Geologica Polonica, Vol. 68 (2018), No. 3, pp. 275–306 DOI: 10.1515/agp-2018-0024 A redescription of Tesseraspis mosaica Karatajūtė-Talimaa, 1983 (Vertebrata: †Pteraspidomorphi: Heterostraci) from the Lochkovian (Lower Devonian) of Severnaya Zemlya, Russia, with a review of tessellated heterostracan taxa ALAIN BLIECK1, DAVID K. ELLIOTT2 and VALENTINA N. KARATAJŪTĖ-TALIMAA3 1 38 rou Paul Daumer, F-59320, Haubordin, France. E-mail: [email protected] 2 Division of Geology, SES, Northern Arizona University, Flagstaff AZ 86011-4099, USA. E-mail: [email protected] 3 Architektu 3–60, Lazdynai, LT-03223 Vilnius, Lithuania. ABSTRACT: Blieck, A., Elliott, D.K. and Karatajūtė-Talimaa, V.N. 2018. A redescription of Tesseraspis mosaica Karatajūtė- Talimaa, 1983 (Vertebrata: †Pteraspidomorphi: Heterostraci) from the Lochkovian (Lower Devonian) of Severnaya Zemlya, Russia, with a review of tessellated heterostracan taxa. Acta Geologica Polonica, 68 (3), 275–306. Warszawa. Material of tesseraspids (Tesseraspidiformes) is reported from the uppermost Severnaya Zemlya Formation (Lochkovian, Lower Devonian) of the Severnaya Zemlya archipelago, in the Russian Arctic, where it is as- sociated with other vertebrate remains, including corvaspids, acanthodians, and large but rare specimens of osteostracans. The tesseraspid material is not abundant, and most often preserved as a “patchwork” of bony platelets (tesserae), except for a few partly articulated specimens. We redescribe the holotype of Tesseraspis mosaica Karatajūtė-Talimaa, 1983, whose head carapace is preserved as a flattened tube of adjacent tesserae. This material is compared to the already published tesseraspid taxa, i.e., T. tessellata Wills, 1935, T. toombsi Tarlo, 1964, T. mutabilis (Brotzen, 1934), T. oervigi Tarlo, 1964 emend.
    [Show full text]
  • The Nature of Aspidin and the Evolutionary Origin of Bone
    ARTICLES https://doi.org/10.1038/s41559-018-0624-1 The nature of aspidin and the evolutionary origin of bone Joseph N. Keating 1,2*, Chloe L. Marquart1, Federica Marone3 and Philip C. J. Donoghue 1* Bone is the key innovation underpinning the evolution of the vertebrate skeleton, yet its origin is mired by debate over inter- pretation of the most primitive bone-like tissue, aspidin. This has variously been interpreted as cellular bone, acellular bone, dentine or an intermediate of dentine and bone. The crux of the controversy is the nature of unmineralized spaces pervad- ing the aspidin matrix, which have alternatively been interpreted as having housed cells, cell processes or Sharpey’s fibres. Discriminating between these hypotheses has been hindered by the limits of traditional histological methods. Here, we use synchrotron X-ray tomographic microscopy to reveal the nature of aspidin. We show that the spaces exhibit a linear morphol- ogy incompatible with interpretations that they represent voids left by cells or cell processes. Instead, these spaces represent intrinsic collagen fibre bundles that form a scaffold about which mineral was deposited. Aspidin is thus acellular dermal bone. We reject hypotheses that it is a type of dentine, cellular bone or transitional tissue. Our study suggests that the full repertoire of skeletal tissue types was established before the divergence of the earliest known skeletonizing vertebrates, indicating that the corresponding cell types evolved rapidly following the divergence of cyclostomes and gnathostomes. he origin of the vertebrate mineralized skeleton, and of its of living vertebrates, allowing us to test hypotheses concerning the canonical suite of cell and tissue types, predates the radiation identity of the aspidin spaces and, in turn, reveal the nature of this Tof crown gnathostomes.
    [Show full text]