Results 121 to 130 of about 327 (156)

Histological structure of the cancellous bone layer in Bothriolepis canadensis (Antiarchi, Placodermi)

Lethaia, 2005
The Placodermi are extinct basal gnathostomes which had extensive dermal and perichondral bone, but which lacked the endochondral bone which characterizes the more derived bony fishes. Thin sections of bone from a specimen of the antiarch placoderm Bothriolepis canadensis, from the Escuminac Formation ( Frasnian, Upper Devonian), Quebec, Canada, reveal
Carole J. Burrow, Burrow, C. J.
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Vascularization of the osteostracan and antiarch (Placodermi) pectoral fin: similarities, and implications for placoderm relationships

Lethaia, 2002
Phylogenetic analyses frequently resolve the extinct group Placodermi at the base of the clade of jawed fishes (traditionally known as the Gnathostomata), with the jawless fish group Osteostraci as sister taxon to this clade. Both gnathostomes and osteostracans possess pectoral fins supported by a radial(s) articulating on a cartilaginous ...
Zerina Johanson
exaly   +2 more sources

Middle Devonian coccosteid (Arthrodira, Placodermi) biostratigraphy of Scotland and Estonia

Scottish Journal of Geology, 2017
A coccosteid nuchal bone from the Middle Devonian Tamme Cliffs locality in Estonia is described as Dickosteus cf. threiplandi , D . threiplandi being a common species in the Middle Devonian of the Orcadian Basin, Scotland.
Michael J. Newman, Jan L. Den Blaauwen, Tormi Tuuling   +2 more
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Skeletal histology of Bothriolepis canadensis (Placodermi, Antiarchi) and evolution of the skeleton at the origin of jawed vertebrates

Journal of Morphology, 2009
AbstractWe used light microscopy and scanning electron microscopy to compile a complete histological description of the dermal skeleton of the antiarch placoderm, Bothriolepis canadensis. Placodermi is most often cited as the sister group of crown group Gnathostomata, but some recent authors propose that placoderms instead represent a paraphyly of ...
Downs, JP, Donoghue, PCJ
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Placodermi pražské pánve (spodní paleozoikum barrandienské oblasti)

, 2010
Placoderms are restricted to the Devonian in the Prague Basin, occuring on localities dated from the Lochkovian to the Givetian. Černá rokle near Kosoř with the Radotin Limestone is the richest placoderm bearing locality. A revision of specimens from collections of the National Museum in Pra- gue confirms occurences of three species of two genera ...
Kašpar Vaškaninová, Valéria
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Placodermi Diet

, 2018
Kate Trinajstic, Brett Roelofs
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Late Devonian Bothriolepidids (Placodermi, Antiarchi) of the Tver Oblast

Paleontological Journal, 2020
The species Livnolepis heckeri (Luksevics, 2001) which had been assigned to the genus Bothriolepis at first description, was described from the Famennian sediments (Upper Devonian) of the Tver oblast. New materials collected from a type locality near the village of Bilovo enabled considerable expansion of the morphological description of the species ...
S. V. Moloshnikov, V. V. Linkevich
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Gromada PLACODERMI – ryby pancerne, tarczowce, plakodermy

, 2012
Piotr Szrek
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On the status of species ofBothriolepis(Placodermi, Antiarchi) in North America

Journal of Vertebrate Paleontology, 2001
ABSTRACT Based on new material collected from the Upper Devonian, “Catskill Formation” of Pennsylvania, and a comparison with variation in Bothriolepis canadensis and B. yeungae, it is suggested that the species Bothriolepis minor, B. virginiensis, B. coloradensis, and B.
Keith Stewart Thomson, Bethia Thomas
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Further consideration of the phylogeny and classification of the order Arthrodira (Pisces: Placodermi)

Journal of Vertebrate Paleontology, 1984
ABSTRACT Evaluation of the characters used to determine the phylogeny and classification of arthrodires leads to the following conclusions: Actinolepidae are defined only by characters primitive for the order. Holonematidae are not brachythoracans but are related to Phlyctaeniidae.
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