Results 31 to 40 of about 696 (179)
Placoderm fishes, pharyngeal denticles, and the vertebrate dentition
Journal of Morphology, 2003 AbstractThe correlation of the origin of teeth with jaws in vertebrate history has recently been challenged with an alternative to the canonical view of teeth deriving from separate skin denticles. This alternative proposes that organized denticle whorls on the pharyngeal (gill) arches in the fossil jawless fish Loganellia are precursors to tooth ...
Johanson, Z, Smith, M M
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Vascularization and odontode structure of a dorsal ridge spine of Romundina stellina Ørvig 1975. [PDF]
PLoS ONE, 2017 There are two types of dermal skeletons in jawed vertebrates: placoderms and osteichthyans carry large bony plates (macromery), whereas chondrichthyans and acanthodians are covered by small scales (micromery).
Anna Jerve +4 more
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Revision of asterolepidoid antiarch remains from the Ogre Formation (Upper Devonian) of Latvia [PDF]
Estonian Journal of Earth Sciences, 2020 The Frasnian (Upper Devonian) antiarch Walterilepis speciosa was first described in 1933 (as Taeniolepis) on the basis of a single specimen. The newly collected material has allowed the head to be described in a more detail, especially the nuchal and ...
Ervīns Lukševičs
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Acta Palaeontologica Polonica, 2023 Sarcopterygian remains are relatively common in the so-called “Placoderm Sandstone” (storm-origin bone-bearing breccia) from the Emsian (Lower Devonian) of Podłazie in the Holy Cross Mountains (Poland).
OLGA WILK
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The relationship of placoderms [PDF]
Journal of Vertebrate Paleontology, 1984 ABSTRACT A review of the evidence suggests that placoderms are more closely related to osteichthyans than chondrichthyans. A new phylogeny of placoderms is proposed in which the ptyctodonts are considered the collateral descendants of all other placoderms.
Long, J. +11 more
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Placoderm muscles and chordate interrelationships [PDF]
Biology Letters, 2007 [Trinajstic et al. (2007)][1] reported exceptionally preserved soft tissues in two placoderm fish from the Devonian of Australia. This exciting finding presents fresh morphological data with a bearing on an old phylogenetic problem: deep branching structure within the vertebrate tree.
Friedman, M, Brazeau, M, Brazeau, M
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Did placoderm fish have teeth?
Journal of Vertebrate Paleontology, 2003 Gavin C. Young
exaly +2 more sources
Loss in the making: absence of pelvic fins and presence of paedomorphic pelvic girdles in a Late Devonian antiarch placoderm (jawed stem-gnathostome) [PDF]
Biology Letters, 2018 Richard Cloutier +2 more
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A new Lower Devonian arthrodire (Placodermi) from the NW Siberian Platform [PDF]
Estonian Journal of Earth Sciences, 2013 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.
Elga Mark-Kurik
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A new Early Devonian antiarch placoderm from Belarus, and the phylogeny of Asterolepidoidei [PDF]
Acta Palaeontologica Polonica, 2023 A new asterolepidoid antiarch, Sherbonaspis talimaae sp. nov., is described based on the disarticulated skeletal elements from several boreholes in Belarus, from the Lepel Beds of the Vitebsk Formation, which has been assigned to an Early Devonian, late ...
Dmitry P. Plax, Ervins Lukševičs
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