Discerning the Diets of Sweep-Feeding Eurypterids Through Analyses of Mesh-Modified Appendage Armature
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Functional Morphology and Evolu Tion of Xiphosurids
Func tional morphol ogy and evolu tion of xiphosurids JAN BERGSTROM Bergstrom, J. 1 975 07 15: Functional morphology and evolution of xiphosurids. Fossils and Strata, No. 4, pp. 291-305, Pl. 1. Oslo. ISSN 0300-9491. ISBN 82-00-04963-9. Aspects of the morphology, evolution and systematics of the Xiphosurida are treated. The ancestrai forms lacked specialization for ploughing, and their chilaria were evidently developed as prosomal walking legs. The cor responding tergite (of the pregenital segment) was probably separate from the main prosomal shield in the early xiphosurids as well as in the eurypter ids. From this stem two main groups seem to have evolved. One consists of the synziphosurids, large-eyed eurypterid-like hunters with stri king opistho somal tagmosis. The other consists of the burrowing and ploughing xipho surids, in which the opisthosomal tergites were subject to progressive fusion ending with a single opisthothoracic tergal shield in the Late Palaeo zoic. The last prosomal appendages evolved into the chilaria, if this did not happen earlier, and the corresponding free tergite disappeared. Probably in Carboniferous time the limulines came into existence through a sudden displacement of the prosomal/opisthosomal boundary. Jan Bergstram, Department of His torical Geology and Palaeontology, Un iversity of Lund, Solvegatan 13, S-223 62 Lund, 1st August 1973. The Xiphosura may be considered to constitute a subdass or dass of chelicerate arthropods. The delimitation has been diseussed in the past, but no general agreement seems to exist. Generally, the xiphosurids are induded with the aglaspidids and eurypterids in the Merostorna ta. However, as generally understood, this taxon probably represents an evolutionary grade rather than a phylogenetic unit. -
A New Eurypterid from the Saaremaa- (Oesel-) Beds in Estonia
TARTU ÜLIKOOLI GEOLOOGIA-INSTITUUDI TOIMETUSED .M 37 PUBLIGA TIONS OF THE GEOLOGICAL INSTITUTION .M 37 OF THE UNIVERSITY OF TARTU A NEW EURYPTERID FROM THE SAAREMAA- (OESEL-) BEDS IN ESTONIA BY LEIF STÖRMER TARTU 1934 K. Mattieseni trükikoda o-ü., Tartu 1934. A new Eurypterid from the Saaremaa- (Oesal-) bads in Estonia. B y L ei f Stör m er. The famous Eurypterus fi�cheri-faunaof Rootsiküla (Rootziküll), Saaremaa, became known to science through the monographs of N iesz kow sk i (1858), Sc hmidt (1.883), and Ho lm (1898). The unique preservation of the eurypterid shells has made it possible to study in detail the finest morphv logical structures of these old arthropods. By means of a special metbod, Ho lm succeeded in separating the chitinaus tests from the matrix. The Saaremaa beds have also furnished a considerable supply of vertebrates and crustaceans. In later years Professor dr. W. Patten from Dartmouth College, Hanover, N. H., U. S. A. made extensive collections in tbe Saaremaa beds. He was specially interested in the remains of the primitive vertebra tes, but also collected a considerable mate rial of merostomes. The sad death of Professor Pat.ten in the fall of 1932 prevented him frorn finishing bis interesting studies on the valuable material of prim itive >ertebrates. In May 1932 I had the fortunate opportunity to visit Professor Patten in Dartmouth Col lege. He very kindly showed me bis fine collections of eurypterids from Saaremaa. Looking through the material I became aware of an eurypterid specimen , belanging to a genus not known, from tbe Eurypterus fischeri-fauna of Saaremaa. -
2019 FSG Report
IUCN SSC Flamingo Specialist Group 2019 Report Cathy King Paul Rose Co-chairs Mission statement tion scientists and flamingo biologists will result Cathy King (1) The mission statement of the WI-IUCN SSC in increased exposure for these species, and Paul Rose (2) Flamingo Specialist Group (FSG) is to actively therefore, a better chance of secured popula- promote flamingo research and conservation tions for the future. We hope that by continuing Red List Authority worldwide by developing conservation action to support the work of scientists and flamingo biologists in the field, the conservation status BirdLife International plans for the most threatened species, and by encouraging information exchange and coop- of all six species does not deteriorate, and that those species currently Vulnerable or Near Location/Affiliation eration amongst flamingo specialists, and Threatened can be more secured in their habi- (1) Zoo de Lagos, Portugal with other relevant organisations, particularly tats, so that future assessments of populations (2) WWT Slimbridge Wetland Centre, UK the IUCN Species Survival Commission (SSC), Wetlands International, Ramsar Convention, show an upward trend in numbers, rather than a decline. The good work currently undertaken Number of members WWF International and BirdLife International. with the Andean and Puna Flamingos (Phoen- 196 icoparrus andinus and P. jamesi, showing stable Projected impact for the 2017-2020 population trends) needs to be monitored, as quadrennium Social networks current Red Lists assessments suggest poten- Facebook: Flamingo Specialist Group By the end of 2020, we hope to have succeeded tial declines due to past poor breeding success Twitter: @FlamingoSpecGrp in our aims of re-launching the FSG website and human-caused impacts on populations. -
(Chelicerata: Eurypterida), a Large Sweep-Feeder from the Carboniferous of South Africa C
Transactions of rhe Royal Society of Edinburgh, 76, 339-358, J985 CyrtoctefJUS wittebergensis sp. nov. (Chelicerata: Eurypterida), a large sweep-feeder from the Carboniferous of South Africa C. D. Waterston, B. W. Oelofsen, R. D. F. Oosthuizen ABSTRACT: Cyrtoctenus winebergensis sp. nov. is described from a unique holotype from the Witteberg Group of the Cape Supergroup. It is a giant hibbertopteroid eurypterid having combs and specialised movable spines of crytoctenid type (St0rmer & Waterston 1968) on the more distal podomeres of the second to fourth prosoroal appendages. The function of the combs and their associated movable spines is discussed and it is suggested that together they formed a unique adaptation of eurypterid structures to sweep filter~feeding, the combs forming the filters and the spines the cleaners. The digestive tract is remarkably preserved and shows a spiral valve, posterior to tbe stomach, which is interpreted as an adaptive feature in this large arthropod to increase tbe absorptive area of the gut. The new evidence provided by the South African specimen bas required the re~interpretation of the disarticulated Cyrloclenus specimens previously described from Europe. Disjecla membra recently obtained from the Tournaisian of Foulden, Berwickshire, whicb may belong to CynoClenus, are described and show characters previously unknown in Scottish material but similar to certain features in the South African specimen. The taxonomic relationships within the Hibbertopteroidea are discussed in the light of tbe new combination of characters found in C. wittebergensis. Two families are recognised in the superfamily, the Hibbertopteridae, including Hibber/opterus and Campylocephalus, and the new family Cyrtoctenidae which is here erected to include Cyrtoclenus, Dunsoprerus and possibly also Haslimima. -
Chelicerata; Eurypterida) from the Campbellton Formation, New Brunswick, Canada Randall F
Document generated on 10/01/2021 9:05 a.m. Atlantic Geology Nineteenth century collections of Pterygotus anglicus Agassiz (Chelicerata; Eurypterida) from the Campbellton Formation, New Brunswick, Canada Randall F. Miller Volume 43, 2007 Article abstract The Devonian fauna from the Campbellton Formation of northern New URI: https://id.erudit.org/iderudit/ageo43art12 Brunswick was discovered in 1881 at the classic locality in Campbellton. About a decade later A.S. Woodward at the British Museum (Natural History) (now See table of contents the Natural History Museum, London) acquired specimens through fossil dealer R.F. Damon. Woodward was among the first to describe the fish assemblage of ostracoderms, arthrodires, acanthodians and chondrichthyans. Publisher(s) At the same time the museum also acquired specimens of a large pterygotid eurypterid. Although the vertebrates received considerable attention, the Atlantic Geoscience Society pterygotids at the Natural History Museum, London are described here for the first time. The first pterygotid specimens collected in 1881 by the Geological ISSN Survey of Canada were later identified by Clarke and Ruedemann in 1912 as Pterygotus atlanticus, although they suggested it might be a variant of 0843-5561 (print) Pterygotus anglicus Agassiz. An almost complete pterygotid recovered in 1994 1718-7885 (digital) from the Campbellton Formation at a new locality in Atholville, less than two kilometres west of Campbellton, has been identified as P. anglicus Agassiz. Like Explore this journal the specimens described by Clarke and Ruedemann, the material from the Natural History Museum, London is herein referred to P. anglicus. Cite this article Miller, R. F. (2007). Nineteenth century collections of Pterygotus anglicus Agassiz (Chelicerata; Eurypterida) from the Campbellton Formation, New Brunswick, Canada. -
Hypothesis of Eurypterid Palaeoecology
Palaeogeography, Palaeoclimatology, Palaeoecology 311 (2011) 63–73 Contents lists available at SciVerse ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Testing the ‘mass-moult-mate’ hypothesis of eurypterid palaeoecology Matthew B. Vrazo ⁎, Simon J. Braddy Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol, BS8 1RJ, UK article info abstract Article history: The eurypterids (Arthropoda: Chelicerata), some of the earliest arthropods to undertake amphibious Received 6 May 2011 excursions onto land, are generally rare in the fossil record, but are sometimes found in great abundance, for Received in revised form 16 July 2011 example in the Late Silurian Bertie Group of New York State. The mass-moult-mate hypothesis has been Accepted 29 July 2011 proposed to explain such occurrences, whereby eurypterids undertook mass migrations into near shore Available online 5 August 2011 settings and lagoons to moult, mate and spawn, similar to the behaviour of living horseshoe crabs. This hypothesis is tested using measurements from over 600 Eurypterus specimens from three localities in the Keywords: Arthropod Bertie Group; Eurypterus remipes, from the Fiddlers Green Formation, and the slightly larger Eurypterus Exuvia lacustris, from the overlying Williamsville Formation. Disarticulation patterns support previous evidence for Taphonomy moulted assemblages. A significant predominance of female exuviae is noted at each locality, unlike studies on Biofacies modern Limulus populations. Therefore, a modified mass-mate-spawn-moult hypothesis is proposed here: Silurian males returned to deeper waters after mating, whereas females, having mated, remained at the breeding sites Eurypterus to deposit their eggs before moulting. After hatching, eurypterid larvae and juveniles remained in these spawning grounds until they matured and could move to deeper water, in comparison with Limulus. -
Description of the Hollidaysburg and Huntingdon Quadrangles
DESCRIPTION OF THE HOLLIDAYSBURG AND HUNTINGDON QUADRANGLES By Charles Butts INTRODUCTION 1 BLUE RIDGE PROVINCE topography are therefore prominent ridges separated by deep SITUATION The Blue Ridge province, narrow at its north end in valleys, all trending northeastward. The Hollidaysburg and Huntingdon quadrangles are adjoin Virginia and Pennsylvania, is over 60 miles wide in North RELIEF ing areas in the south-central part of Pennsylvania, in Blair, Carolina. It is a rugged region of hills and ridges and deep, The lowest point in the quadrangles is at Huntingdon, Bedford, and Huntingdon Counties. (See fig. 1.) Taken as narrow valleys. The altitude of the higher summits in Vir where the altitude of the river bed is about 610 feet above sea ginia is 3,000 to 5,700 feet, and in western North Carolina 79 level, and the highest point is the southern extremity of Brush Mount Mitchell, 6,711 feet high, is the highest point east of Mountain, north of Hollidaysburg, which is 2,520 feet above the Mississippi River. Throughout its extent this province sea level. The extreme relief is thus 1,910 feet. The Alle stands up conspicuously above the bordering provinces, from gheny Front and Dunning, Short, Loop, Lock, Tussey, Ter each of which it is separated by a steep, broken, rugged front race, and Broadtop Mountains rise boldly 800 to 1,500 feet from 1,000 to 3,000 feet high. In Pennsylvania, however, above the valley bottoms in a distance of 1 to 2 miles and are South Mountain, the northeast end of the Blue Ridge, is less the dominating features of the landscape. -
Segmentation and Tagmosis in Chelicerata
Arthropod Structure & Development 46 (2017) 395e418 Contents lists available at ScienceDirect Arthropod Structure & Development journal homepage: www.elsevier.com/locate/asd Segmentation and tagmosis in Chelicerata * Jason A. Dunlop a, , James C. Lamsdell b a Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstrasse 43, D-10115 Berlin, Germany b American Museum of Natural History, Division of Paleontology, Central Park West at 79th St, New York, NY 10024, USA article info abstract Article history: Patterns of segmentation and tagmosis are reviewed for Chelicerata. Depending on the outgroup, che- Received 4 April 2016 licerate origins are either among taxa with an anterior tagma of six somites, or taxa in which the ap- Accepted 18 May 2016 pendages of somite I became increasingly raptorial. All Chelicerata have appendage I as a chelate or Available online 21 June 2016 clasp-knife chelicera. The basic trend has obviously been to consolidate food-gathering and walking limbs as a prosoma and respiratory appendages on the opisthosoma. However, the boundary of the Keywords: prosoma is debatable in that some taxa have functionally incorporated somite VII and/or its appendages Arthropoda into the prosoma. Euchelicerata can be defined on having plate-like opisthosomal appendages, further Chelicerata fi Tagmosis modi ed within Arachnida. Total somite counts for Chelicerata range from a maximum of nineteen in Prosoma groups like Scorpiones and the extinct Eurypterida down to seven in modern Pycnogonida. Mites may Opisthosoma also show reduced somite counts, but reconstructing segmentation in these animals remains chal- lenging. Several innovations relating to tagmosis or the appendages borne on particular somites are summarised here as putative apomorphies of individual higher taxa. -
Geological History and Phylogeny of Chelicerata
Arthropod Structure & Development 39 (2010) 124–142 Contents lists available at ScienceDirect Arthropod Structure & Development journal homepage: www.elsevier.com/locate/asd Review Article Geological history and phylogeny of Chelicerata Jason A. Dunlop* Museum fu¨r Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity at the Humboldt University Berlin, Invalidenstraße 43, D-10115 Berlin, Germany article info abstract Article history: Chelicerata probably appeared during the Cambrian period. Their precise origins remain unclear, but may Received 1 December 2009 lie among the so-called great appendage arthropods. By the late Cambrian there is evidence for both Accepted 13 January 2010 Pycnogonida and Euchelicerata. Relationships between the principal euchelicerate lineages are unre- solved, but Xiphosura, Eurypterida and Chasmataspidida (the last two extinct), are all known as body Keywords: fossils from the Ordovician. The fourth group, Arachnida, was found monophyletic in most recent studies. Arachnida Arachnids are known unequivocally from the Silurian (a putative Ordovician mite remains controversial), Fossil record and the balance of evidence favours a common, terrestrial ancestor. Recent work recognises four prin- Phylogeny Evolutionary tree cipal arachnid clades: Stethostomata, Haplocnemata, Acaromorpha and Pantetrapulmonata, of which the pantetrapulmonates (spiders and their relatives) are probably the most robust grouping. Stethostomata includes Scorpiones (Silurian–Recent) and Opiliones (Devonian–Recent), while -
Phylum Arthropoda*
Zootaxa 3703 (1): 017–026 ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ Correspondence ZOOTAXA Copyright © 2013 Magnolia Press ISSN 1175-5334 (online edition) http://dx.doi.org/10.11646/zootaxa.3703.1.6 http://zoobank.org/urn:lsid:zoobank.org:pub:FBDB78E3-21AB-46E6-BD4F-A4ADBB940DCC Phylum Arthropoda* ZHI-QIANG ZHANG New Zealand Arthropod Collection, Landcare Research, Private Bag 92170, Auckland, New Zealand; [email protected] * In: Zhang, Z.-Q. (Ed.) Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (Addenda 2013). Zootaxa, 3703, 1–82. Abstract The Arthropoda is here estimated to have 1,302,809 described species, including 45,769 fossil species (the diversity of fossil taxa is here underestimated for many taxa of the Arthropoda). The Insecta (1,070,781 species) is the most successful group, and it alone accounts for over 80% of all arthropods. The most successful insect order, Coleoptera (392,415 species), represents over one-third of all species in 39 insect orders. Another major group in Arthropoda is the class Arachnida (114,275 species), which is dominated by the Acari (55,214 mite and tick species) and Araneae (44,863 spider species). Other diverse arthropod groups include Crustacea (73,141 species), Trilobitomorpha (20,906 species) and Myriapoda (12,010 species). Key words: Classification, diversity, Arthropoda Introduction The Arthropoda, with over 1.5 million described species, is the largest animal phylum, and it alone accounts for about 80% of the total number of species in the animal kingdom (Zhang 2011a). In the last volume on animal higher-level classification and survey of taxonomic richness, 28 chapters by numerous teams of specialists were published on various taxa of the Arthropoda, but there were many gaps to be filled (Zhang 2011b). -
Tayside, Central and Fife Tayside, Central and Fife
Detail of the Lower Devonian jawless, armoured fish Cephalaspis from Balruddery Den. © Perth Museum & Art Gallery, Perth & Kinross Council Review of Fossil Collections in Scotland Tayside, Central and Fife Tayside, Central and Fife Stirling Smith Art Gallery and Museum Perth Museum and Art Gallery (Culture Perth and Kinross) The McManus: Dundee’s Art Gallery and Museum (Leisure and Culture Dundee) Broughty Castle (Leisure and Culture Dundee) D’Arcy Thompson Zoology Museum and University Herbarium (University of Dundee Museum Collections) Montrose Museum (Angus Alive) Museums of the University of St Andrews Fife Collections Centre (Fife Cultural Trust) St Andrews Museum (Fife Cultural Trust) Kirkcaldy Galleries (Fife Cultural Trust) Falkirk Collections Centre (Falkirk Community Trust) 1 Stirling Smith Art Gallery and Museum Collection type: Independent Accreditation: 2016 Dumbarton Road, Stirling, FK8 2KR Contact: [email protected] Location of collections The Smith Art Gallery and Museum, formerly known as the Smith Institute, was established at the bequest of artist Thomas Stuart Smith (1815-1869) on land supplied by the Burgh of Stirling. The Institute opened in 1874. Fossils are housed onsite in one of several storerooms. Size of collections 700 fossils. Onsite records The CMS has recently been updated to Adlib (Axiel Collection); all fossils have a basic entry with additional details on MDA cards. Collection highlights 1. Fossils linked to Robert Kidston (1852-1924). 2. Silurian graptolite fossils linked to Professor Henry Alleyne Nicholson (1844-1899). 3. Dura Den fossils linked to Reverend John Anderson (1796-1864). Published information Traquair, R.H. (1900). XXXII.—Report on Fossil Fishes collected by the Geological Survey of Scotland in the Silurian Rocks of the South of Scotland. -
Flamingo Atlas
Flamingo Bulletin of the IUCN-SSC/Wetlands International FLAMINGO SPECIALIST GROUP Number 15, December 2007 ISSN 1680-1857 ABOUT THE GROUP The Flamingo Specialist Group (FSG) was established in 1978 at Tour du Valat in France, under the leadership of Dr. Alan Johnson, who coordinated the group until 2004. Currently, the group is coordinated from the Wildfowl & Wetlands Trust at Slimbridge, UK, as part of the IUCN-SSC/Wetlands International Waterbird Network. The FSG is a global network of flamingo specialists (both scientists and non- scientists) involved in the study, monitoring, management and conservation of the world’s six flamingo species populations. Its role is to actively promote flamingo research and conservation worldwide by encouraging information exchange and cooperation among these specialists, and with other relevant organisations, particularly IUCN - SSC, Wetlands International, Ramsar, Convention on the Conservation of Migratory Species, African Eurasian Migratory Waterbird Agreement, and BirdLife International. FSG members include experts in both in-situ (wild) and ex-situ (captive) flamingo conservation, as well as in fields ranging from field surveys to breeding biology, infectious diseases, toxicology, movement tracking and data management. There are currently 208 members around the world, from India to Chile, and from Finland to South Africa. Further information about the FSG, its membership, the membership list serve, or this bulletin can be obtained from Brooks Childress at the address below. Chair Assistant Chair Dr. Brooks Childress Mr. Nigel Jarrett Wildfowl & Wetlands Trust Wildfowl & Wetlands Trust Slimbridge Slimbridge Glos. GL2 7BT, UK Glos. GL2 7BT, UK Tel: +44 (0)1453 860437 Tel: +44 (0)1453 891177 Fax: +44 (0)1453 860437 Fax: +44 (0)1453 890827 [email protected] [email protected] Eastern Hemisphere Chair Western Hemisphere Chair Dr.