Dunkleosteus Fact Sheet

Total Page：16

File Type：pdf, Size：1020Kb

Dunkleosteus Fact Sheet Common Name: Dunkleosteus terrelli Scientific Name: Dunkle's bone Wild Status: Devonian Period, 382-358 MYA Habitat: North America, Poland, Belgium, Morocco Country: Poland, Belgium, Morocco, Countries in North America Shelter: Unknown Life Span: Unknown Size: 20 feet long, 1.1 tons Details Dunkleosteus is a member of an extinct group of fish known as placoderms. Placoderms had bony armor covering the upper third of their bodies, and were the first fish to evolve teeth and pelvic fins. Instead of teeth, Dunkleosteus’s jaws contained sharpened bony plates that functioned like a guillotine. Due to a specialized joint between its head and neck, Dunkleosteus was able to open its jaws in 20 milliseconds to suck prey into its maw before slamming them shut with more than 1500 pounds of bite force to shear them to pieces. At the time, it was the largest and most powerful predator on the planet. Cool Facts • Even though it was a top predator that could prey on just about any other animal it wanted to, Dunkleosteus could not digest bone. It is common to find masses of partially digested fish bones associated with Dunkleosteus fossils. This indicates that they routinely regurgitated the inedible parts of prey. • Dunkleosteus is only known from its head armor. Its body was made made of cartilage and does not preserve in the fossil record. As a result of this, scientists do not know for sure exactly what the animal looked like in life. Taxonomic Breakdown Kingdom: Animalia Phylum: Chordata Class: Placodermi Order: Arthrodira Family: Dunkleosteidae Genus: Dunkleosteus Species: D. terrelli Conservation & Helping Dunkleosteus is currently extinct and lived from 382 to 358 million years ago. Download all our fact sheets, take our quizzes, and more, all in the Critter Squad Kids’ Zone! https://www.crittersquad.com/kids-zone/.

Copy Link

Recommended publications

FISHING for DUNKLEOSTEUS You’Re Definitely Gonna Need a Bigger Boat by Mark Peter
OOhhiioo GGeeoollooggyy EEXXTTRRAA July 31, 2019 FISHING FOR DUNKLEOSTEUS You’re definitely gonna need a bigger boat by Mark Peter At an estimated maximum length of 6 to 8.8 meters (20–29 sediments that eroded from the Acadian Mountains, combined feet), Dunkleosteus terrelli (Fig. 1) would have been a match for with abundant organic matter from newly evolved land plants even the Hollywood-sized great white shark from the and marine plankton, settled in the basin as dark organic movie Jaws. Surfers, scuba divers, and swimmers can relax, muds. Over millions of years, accumulation of additional however, because Dunkleosteus has been extinct for nearly 360 overlying sediments compacted the muds into black shale rock. million years. Dunkleosteus was a placoderm, a type of armored The rocks that formed from the Late Devonian seafloor fish, that lived during the Late Devonian Period from about sediments (along with fossils of Dunkleosteus) arrived at their 375–359 million years ago. Fossil remains of the large present location of 41 degrees north latitude after several species Dunkleosteus terrelli are present in the Cleveland hundred million years of slow plate tectonic movement as the Member of the Ohio Shale, which contains rocks that are North American Plate moved northward. approximately 360–359 million years old. Figure 1. A reconstruction of a fully-grown Dunkleosteus terrelli, assuming a length of 29 feet, with angler for scale. Modified from illustration by Hugo Salais of Metazoa Studio. Dunkleosteus cruised Late Devonian seas and oceans as an Figure 2. Paleogeographic reconstruction of eastern North America during apex predator, much like the great white shark of today.
[Show full text]
'Placoderm' (Arthrodira)
Jobbins et al. Swiss J Palaeontol (2021) 140:2 https://doi.org/10.1186/s13358-020-00212-w Swiss Journal of Palaeontology RESEARCH ARTICLE Open Access A large Middle Devonian eubrachythoracid ‘placoderm’ (Arthrodira) jaw from northern Gondwana Melina Jobbins1* , Martin Rücklin2, Thodoris Argyriou3 and Christian Klug1 Abstract For the understanding of the evolution of jawed vertebrates and jaws and teeth, ‘placoderms’ are crucial as they exhibit an impressive morphological disparity associated with the early stages of this process. The Devonian of Morocco is famous for its rich occurrences of arthrodire ‘placoderms’. While Late Devonian strata are rich in arthrodire remains, they are less common in older strata. Here, we describe a large tooth-bearing jaw element of Leptodontich- thys ziregensis gen. et sp. nov., an eubrachythoracid arthrodire from the Middle Devonian of Morocco. This species is based on a large posterior superognathal with a strong dentition. The jawbone displays features considered syna- pomorphies of Late Devonian eubrachythoracid arthrodires, with one posterior and one lateral row of conical teeth oriented postero-lingually. μCT-images reveal internal structures including pulp cavities and dentinous tissues. The posterior orientation of the teeth and the traces of a putative occlusal contact on the lingual side of the bone imply that these teeth were hardly used for feeding. Similar to Compagopiscis and Plourdosteus, functional teeth were pos- sibly present during an earlier developmental stage and have been worn entirely. The morphological features of the jaw element suggest a close relationship with plourdosteids. Its size implies that the animal was rather large. Keywords: Arthrodira, Dentition, Food web, Givetian, Maïder basin, Palaeoecology Introduction important to reconstruct character evolution in early ‘Placoderms’ are considered as a paraphyletic grade vertebrates.
[Show full text]
Arthrodira, Homostiidae) from the Emsian of Aragón, Spain, and Its Distribution
FISH FROM THE EMSIAN OF ARAGÓN 139 Tityosteus, A MARINE FISH (ARTHRODIRA, HOMOSTIIDAE) FROM THE EMSIAN OF ARAGÓN, SPAIN, AND ITS DISTRIBUTION Elga MARK-KURIK1 and Peter CARLS2 1 Institute of Geology. Tallinn University of Technology, Estonia Avenue 7, 10143 Tallinn, Estonia. E-mail: [email protected] 2 Institut für Umweltgeologie, Technische Universität, Braunschweig, Pockels- Str. 3, D 38106, Germany. Mark-Kurik, E. and Carls, P. 2004. Tityosteus, a marine fish (Arthrodira, Homostiidae) from the Emsian of Aragón, Spain, and its distribution. [Tityosteus, un pez marino (Arthrodira, Homostiidae) del Emsiense de Aragón, España, y su distribución.] Revista Española de Paleontología, 19 (2), 139-144. ISSN 0213-6937. ABSTRACT A right marginal plate (over 11 cm long) of Tityosteus cf. rieversae Gross, 1960, emend., has been found in the late part of the Early Emsian (late Zlichovian) in the Mariposas Fm. of the Eastern Iberian Cordillera in south- ern Aragón. The palaeoecological conditions correspond to a hemipelagic ensialic basin, with predominant ele- ments of Hercynic biofacies but still with photic bottom. The Emsian genus Tityosteus is now known from the Hunsrück Schiefer of Germany and the closely connected Ibero-Armorican Trough and also from the more dis- tant Minusinsk Basin of southern Siberia. Palaeo-oceans between western Europe and southern Siberia were no zoogeographical barriers for these large, possibly microphagous fishes in open sea. The name of the type spe- cies of Tityosteus is emended. Keywords: Placodermi, marginal plate, palaeoecology, palaeozoogeography, late Zlichovian. RESUMEN Se describe una placa marginal derecha (más de 11 cm de longitud) de Tityosteus cf. rieversae Gross, 1960, emend., de la parte tardía del Emsiense Inferior (Zlichoviense tardío) de la Fm.
[Show full text]
Contributions in BIOLOGY and GEOLOGY
MILWAUKEE PUBLIC MUSEUM Contributions In BIOLOGY and GEOLOGY Number 51 November 29, 1982 A Compendium of Fossil Marine Families J. John Sepkoski, Jr. MILWAUKEE PUBLIC MUSEUM Contributions in BIOLOGY and GEOLOGY Number 51 November 29, 1982 A COMPENDIUM OF FOSSIL MARINE FAMILIES J. JOHN SEPKOSKI, JR. Department of the Geophysical Sciences University of Chicago REVIEWERS FOR THIS PUBLICATION: Robert Gernant, University of Wisconsin-Milwaukee David M. Raup, Field Museum of Natural History Frederick R. Schram, San Diego Natural History Museum Peter M. Sheehan, Milwaukee Public Museum ISBN 0-893260-081-9 Milwaukee Public Museum Press Published by the Order of the Board of Trustees CONTENTS Abstract ---- ---------- -- - ----------------------- 2 Introduction -- --- -- ------ - - - ------- - ----------- - - - 2 Compendium ----------------------------- -- ------ 6 Protozoa ----- - ------- - - - -- -- - -------- - ------ - 6 Porifera------------- --- ---------------------- 9 Archaeocyatha -- - ------ - ------ - - -- ---------- - - - - 14 Coelenterata -- - -- --- -- - - -- - - - - -- - -- - -- - - -- -- - -- 17 Platyhelminthes - - -- - - - -- - - -- - -- - -- - -- -- --- - - - - - - 24 Rhynchocoela - ---- - - - - ---- --- ---- - - ----------- - 24 Priapulida ------ ---- - - - - -- - - -- - ------ - -- ------ 24 Nematoda - -- - --- --- -- - -- --- - -- --- ---- -- - - -- -- 24 Mollusca ------------- --- --------------- ------ 24 Sipunculida ---------- --- ------------ ---- -- --- - 46 Echiurida ------ - --- - - - - - --- --- - -- --- - -- - - ---
[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]
Redescription of Yinostius Major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the Interrelationships of Brachythoraci
bs_bs_banner Zoological Journal of the Linnean Society, 2015. With 10 ﬁgures Redescription of Yinostius major (Arthrodira: Heterostiidae) from the Lower Devonian of China, and the interrelationships of Brachythoraci YOU-AN ZHU1,2, MIN ZHU1* and JUN-QING WANG1 1Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 2University of Chinese Academy of Sciences, Beijing 100049, China Received 29 December 2014; revised 21 August 2015; accepted for publication 23 August 2015 Yinosteus major is a heterostiid arthrodire (Placodermi) from the Lower Devonian Jiucheng Formation of Yunnan Province, south-western China. A detailed redescription of this taxon reveals the morphology of neurocranium and visceral side of skull roof. Yinosteus major shows typical heterostiid characters such as anterodorsally positioned small orbits and rod-like anterior lateral plates. Its neurocranium resembles those of advanced eubrachythoracids rather than basal brachythoracids, and provides new morphological aspects in heterostiids. Phylogenetic analysis based on parsimony was conducted using a revised and expanded data matrix. The analysis yields a novel sce- nario on the brachythoracid interrelationships, which assigns Heterostiidae (including Heterostius ingens and Yinosteus major) as the sister group of Dunkleosteus amblyodoratus. The resulting phylogenetic scenario suggests that eubrachythoracids underwent a rapid diversiﬁcation during the Emsian, representing the placoderm response to the Devonian Nekton Revolution. The instability of the relationships between major eubrachythoracid clades might have a connection to their longer ghost lineages than previous scenarios have implied. © 2015 The Linnean Society of London, Zoological Journal of the Linnean Society, 2015 doi: 10.1111/zoj.12356 ADDITIONAL KEYWORDS: Brachythoraci – Heterostiidae – morphology – phylogeny – Placodermi.
[Show full text]
The Earliest Phyllolepid (Placodermi, Arthrodira) from the Late Lochkovian (Early Devonian) of Yunnan (South China)
Geol. Mag. 145 (2), 2008, pp. 257–278. c 2007 Cambridge University Press 257 doi:10.1017/S0016756807004207 First published online 30 November 2007 Printed in the United Kingdom The earliest phyllolepid (Placodermi, Arthrodira) from the Late Lochkovian (Early Devonian) of Yunnan (South China) V. DUPRET∗ &M.ZHU Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, P.O. Box 643, Xizhimenwai Dajie 142, Beijing 100044, People’s Republic of China (Received 1 November 2006; accepted 26 June 2007) Abstract – Gavinaspis convergens, a new genus and species of the Phyllolepida (Placodermi: Arthrodira), is described on the basis of skull remains from the Late Lochkovian (Xitun Formation, Early Devonian) of Qujing (Yunnan, South China). This new form displays a mosaic of characters of basal actinolepidoid arthrodires and more derived phyllolepids. A new hypothesis is proposed concerning the origin of the unpaired centronuchal plate of the Phyllolepida by a fusion of the paired central plates into one single dermal element and the loss of the nuchal plate. A phylogenetic analysis suggests the position of Gavinaspis gen. nov. as the sister group of the Phyllolepididae, in a distinct new family (Gavinaspididae fam. nov.). This new form suggests a possible Chinese origin for the Phyllolepida or that the common ancestor to Phyllolepida lived in an area including both South China and Gondwana, and in any case corroborates the palaeogeographic proximity between Australia and South China during the Devonian Period. Keywords: Devonian, China, Placodermi, phyllolepids, biostratigraphy, palaeobiogeography. 1. Introduction 1934). Subsequently, they were considered as either sharing an immediate common ancestor with the The Phyllolepida are a peculiar group of the Arthrodira Arthrodira (Denison, 1978), belonging to the Actin- (Placodermi), widespread in the Givetian–Famennian olepidoidei (Long, 1984), or being of indetermined of Gondwana (Australia, Antarctica, Turkey, South position within the Arthrodira (Goujet & Young,1995).
[Show full text]
A Large Late Devonian Arthrodire (Vertebrata, Placodermi) from Poland
Estonian Journal of Earth Sciences, 2018, 67, 1, 33–42 https://doi.org/10.3176/earth.2018.02 A large Late Devonian arthrodire (Vertebrata, Placodermi) from Poland Piotr Szreka and Olga Wilkb a Polish Geological Institute–National Research Institute, 4 Rakowiecka Street, 00-975 Warszawa, Poland; [email protected] b Faculty of Geology, University of Warsaw, 93 Żwirki i Wigury Street, 02-089 Warszawa, Poland; [email protected] Received 1 August 2017, accepted 31 October 2017, available online 19 January 2018 Abstract. The arthrodire placoderm, Dunkleosteus sp., is reported from the Upper Devonian (Frasnian) of the Holy Cross Mountains, Poland. The material comprises partially preserved remains of two individuals found in the Kellwasser-like horizon of the Płucki locality. The remains are preserved as broken bone fragments redeposited from shallower environment into deep-shelf conditions. They are labelled as Dunkleosteus sp. and seem similar to Dunkleosteus marsaisi from the Famennian of Morocco. It is likely that the form from Poland represents a new species that requires further collecting and study of new specimens. The described specimens are the oldest occurrence of the genus Dunkleosteus in Europe, the most complete one from Poland and one of the biggest placoderms with a head about 60 cm long. Key words: Dunkleosteus, Upper Devonian, Frasnian, Holy Cross Mountains, Poland. INTRODUCTION D. marsaisi Lehman, 1954 from the early Famennian of Morocco (Lehman 1956). The genus Dunkleosteus (formerly Dinichthys in part) Although tens of placoderm fossil remains were includes about eight species (if including D. belgicus collected in Płucki during long-term excavation works (Leriche), 1931) which are found in Laurussia (USA, between 1996 and 2006 (see Szrek 2008, 2009; Szrek & Canada, Belgium, Poland) and Gondwana (Morocco).
[Show full text]
Vertebrata: Placodermi) from the Famennian of Belgium
View metadata, citationGEOLOGICA and similar papers BELGICA at core.ac.uk (2005) 8/1-2: 51-67 brought to you by CORE provided by Open Marine Archive A NEW GROENLANDASPIDID ARTHRODIRE (VERTEBRATA: PLACODERMI) FROM THE FAMENNIAN OF BELGIUM Philippe JANVIER1, 2 and Gaël CLÉMENT1 1. UMR 5143 du CNRS, Département «Histoire de la Terre», Muséum National d’Histoire Naturelle, 8 rue Buff on, 75005 Paris, France. [email protected] 2. 7 e Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom (9 fi gures, 1 table and 2 plates) ABSTRACT. A new species of the arthrodire genus Groenlandaspis is described from the upper part of the Evieux Formation (Upper Famennian), based on several specimens collected from quarries at Modave and Villers-le-Temple, Liège Province, Belgium. It is the fi rst occurrence of this widespread genus in continental Europe. O is new species is characterized by an almost smooth dermal armour, except for some scattered tubercles on its skull roof, median dorsal and spinal plates. Its median dorsal plate is triangular in shape and almost perfectly equilateral in lateral aspect and bears large, spiniform denticles on its posterior edge. All these Groenlandaspis remains occur in micaceous, dolomitic claystones or siltstones probably deposited in a subtidal environment. Outcrops of the same area have yielded other vertebrate remains, such as the placoderms Phyllolepis and Bothriolepis, acanthodians, various piscine sarcopterygians (Holoptychius, dipnoans, a rhizodontid, Megalichthys, Eusthenodon and a large tristichopterid), and a tetrapod that is probably close to Ichthyostega. O e biogeographical history of the genus Groenlandaspis is briefl y outlined, and the late Frasnian-Famennian interchange of vertebrate taxa between Gondwana and Euramerica is discussed.
[Show full text]
Comments on the Late Devonian Placoderms from the Holy Cross Mountains (Poland)
Comments on the Late Devonian placoderms from the Holy Cross Mountains (Poland) ALEXANDER IVANOV andMICHAŁ GINTER Ivanov, A. & Ginter,M. 1997. Comments on the Late Devonian placoderms from the Holy Cross Mountains (Poland).- Acta Palaeontologica Polonica 4,3,4I34f6. Taxonomy of the Late Devonian placoderm remains from the Holy Cross Mountains, Poland, described by Gorizdro-Kulczycka (L934,1950) and Kulczycki (1956, 1957),is revised. Several recently found specimens are also mentioned. The old collections are composed of representatives of Ptyctodontidae, Holonematidae, Plourdosteidae, Pholi- dosteidae, Selenosteidae, Titanichthyidae and Dinichthyidae, the latter with an unde- scribed species of Eastmanosteus. Newly found specimens belong to Ptyctodontidae, Plourdosteidae and Dinichthyidae. The occurrence of the Antiarcha in the Late Devonian of the Holy Cross Mountains, suggestedby former authors, has not been confirmed. K e y w o rd s : Placodermi,Late Devonian, Holy Cross Mountains, Poland. Alexander Ivanov [[email protected]], Laboratory of Paleontology, Institute of the Earth Crust, Sankt-Petersburg University, 16 Liniya 29, 199178 St.Petersburg, Russia. Michał Ginter [email protected]], InsĘtut Geologii Podstawowej, Uniwersytet War szaw ski, ul. Zw irki i Wi gury 9 3, 02 -089 War szaw a, P oland. Introduction The main goals of this study are to revise placodermsfrom the Late Devonian of the Holy Cross Mountains collected by Jan Czarnocki, Julian Kulczycki and Zinuda Gorizdro-Kulczycka in the first half of the century (the material now housed in the Museum of the Polish Geological Instituteand in the Museum of the Earth in Warsaw), and to describe a fęw new specimenscollected recently by Jerzy Dzik and Grzegorz Racki.
[Show full text]
A New Lower Devonian Arthrodire (Placodermi) from the NW Siberian Platform
Estonian Journal of Earth Sciences, 2013, 62, 3, 131–138 doi: 10.3176/earth.2013.11 A new Lower Devonian arthrodire (Placodermi) from the NW Siberian Platform Elga Mark-Kurik Institute of Geology at Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia; [email protected] Received 24 August 2012, accepted 5 November 2012 Abstract. A new genus and species of arthrodires, Eukaia elongata (Actinolepidoidei, Placodermi), is described from the Lower Devonian, ?Pragian of the Turukhansk region, NW Siberian Platform. A single specimen of the fish, a skull roof, comes probably from the lower part of the Razvedochnyj Formation. The occurrence of an actinolepidoid arthrodire in the Early Devonian of this area of Siberia is unexpected. Eukaia shows some distant relationship with the genus Actinolepis, but several features indicate similarity to representatives of other arthrodires. Key words: actinolepidoid arthrodire, placoderm, Lower Devonian, ?Pragian, NW Siberian Platform. INTRODUCTION (Fig. 1). The first two units are Lochkovian in age, the lower part of the Razvedochnyj Fm belongs to the Pragian The northwestern part of the Siberian Platform in the and the upper part of the Razvedochnyj Fm plus the lower Russian Arctic is well known for rich and amphiaspidid- part of the Mantura Fm to the Emsian (Matukhin 1995). dominated Early Devonian fish faunas. One of the The Zub Fm (up to 150 m thick) consists of carbonaceous- important areas where these faunas have been discovered argillaceous and sulphate rocks. Invertebrates and fossil is the near-Yenisej zone of the Tunguska syneclise fishes, e.g. a cyathaspidid Steinaspis, are comparatively (Krylova et al.
[Show full text]
Sepkoski, J.J. 1992. Compendium of Fossil Marine Animal Families
MILWAUKEE PUBLIC MUSEUM Contributions . In BIOLOGY and GEOLOGY Number 83 March 1,1992 A Compendium of Fossil Marine Animal Families 2nd edition J. John Sepkoski, Jr. MILWAUKEE PUBLIC MUSEUM Contributions . In BIOLOGY and GEOLOGY Number 83 March 1,1992 A Compendium of Fossil Marine Animal Families 2nd edition J. John Sepkoski, Jr. Department of the Geophysical Sciences University of Chicago Chicago, Illinois 60637 Milwaukee Public Museum Contributions in Biology and Geology Rodney Watkins, Editor (Reviewer for this paper was P.M. Sheehan) This publication is priced at $25.00 and may be obtained by writing to the Museum Gift Shop, Milwaukee Public Museum, 800 West Wells Street, Milwaukee, WI 53233. Orders must also include $3.00 for shipping and handling ($4.00 for foreign destinations) and must be accompanied by money order or check drawn on U.S. bank. Money orders or checks should be made payable to the Milwaukee Public Museum. Wisconsin residents please add 5% sales tax. In addition, a diskette in ASCII format (DOS) containing the data in this publication is priced at $25.00. Diskettes should be ordered from the Geology Section, Milwaukee Public Museum, 800 West Wells Street, Milwaukee, WI 53233. Specify 3Y. inch or 5Y. inch diskette size when ordering. Checks or money orders for diskettes should be made payable to "GeologySection, Milwaukee Public Museum," and fees for shipping and handling included as stated above. Profits support the research effort of the GeologySection. ISBN 0-89326-168-8 ©1992Milwaukee Public Museum Sponsored by Milwaukee County Contents Abstract ....... 1 Introduction.. ... 2 Stratigraphic codes. 8 The Compendium 14 Actinopoda.
[Show full text]