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1
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Revised taxonomy of albanerpetontid amphibians

100%
Gardner J. D.
Acta Palaeontologica Polonica
|
2000
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tom 45
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nr 1
55-70
Characters of the jaws and frontals are often used to differentiate albanerpetontid genera and species, yet the reliability of these characters has rarely been examined. Frontals are diagnostic for the genera Albanerpeton and Celtedens and for species in the latter genus. The value of frontals at the specific level in Celtedens may be inflated by lack of information about variation in jaw structure. Characters of the frontals, jaws, and body size differentiate species of Albanerpeton. Differential diagnoses are presented for the Albanerpetontidae based on cranial and vertebral characters and for the two named genera based on frontal characters. Each genus is characterized by one autapomorphy: fused frontals triangular in Albanerpeton and internasal process bulbous in Celtedens. An enigmatic albanerpetontid from the Middle Jurassic (upper Bathonian) of England has a unique mixture of frontal and premaxillary character states that precludes it from being included in either Celtedens or Albanerpeton.This leaves the oldest occurrences of the two genera in, respectively, the Late Jurassic (Kimmeridgian) and Early Cretaceous (latest Aptian/earliest Albian).
2
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A unique dentary suggests a third genus of batrachosauroidid salamander existed during the latest Cretaceous in the western USA

100%
Gardner J. D.
Acta Palaeontologica Polonica
|
2022
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tom 67
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nr 1
3
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Albanerpetontid amphibians from the Upper Cretaceous of Middle Asia

63%
Gardner J. D., Averianov A. O.
Acta Palaeontologica Polonica
|
1998
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tom 43
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nr 3
453-476
We review the fossil record of Asian albanerpetontids. The three dentaries previously attributed to the two species of Nukusurus Nessov, 1981 (lower Cenomanian and Coniacian, Uzbekistan) are from albanerpetontids, but none are distinctive below the familial level. We thus designate the names Nukusurus, N. insuetus Nessov, 1981, and N. sodalis Nessov, 1997 as nomina dubia within the Albanerpetontidae. Two dentaries (lower Cenomanian, Uzbekistan) described herein for the first time supplement the known record of Asian albanerpetontids. The holotype atlas and only specimen of the supposed albanerpetontid Bishara backa Nessov, 1997 (upper Santonian-?Campanian, Kazakhstan) is shown to be from a salamander, not an albanerpetontid. Our study recognizes Albanerpeton (Cretaceous-Miocene, North America and Europe) and Celtedens (Middle Jurassic-Lower Cretaceous, Europe) as the only valid albanerpetontid genera. Limited evidence favors one or more dispersals from Europe or Norttr America to Asia in the medial Cretaceous as the major biogeographic event in the history of Asian albanerpetontids.
4
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A new albanerpetontid amphibian from the Barremian (Early Cretaceous) Wessex Formation of the Isle of Wight, southern England

63%
Sweetman S. C., Gardner J. D.
Acta Palaeontologica Polonica
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2013
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tom 58
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nr 2
A new albanerpetontid, Wesserpeton evansae gen. et sp. nov., from the Early Cretaceous (Barremian) Wessex Formation of the Isle of Wight, southern England, is described. Wesserpeton is established on the basis of a unique combination of primitive and derived characters relating to the frontals and jaws which render it distinct from currently recognized albanerpetontid genera: Albanerpeton (Late Cretaceous to Pliocene of Europe, Early Cretaceous to Paleocene of North America and Late Cretaceous of Asia); Celtedens (Late Jurassic to Early Cretaceous of Europe); and Anoualerpeton (Middle Jurassic of Europe and Early Cretaceous of North Africa). Although Wesserpeton exhibits considerable intraspecific variation in characters pertaining to the jaws and, to a lesser extent, frontals, the new taxon differs from Celtedens in the shape of the internasal process and gross morphology of the frontals in dorsal or ventral view. It differs from Anoualerpeton in the lack of pronounced heterodonty of dentary and maxillary teeth; and in the more medial loca− tion and direction of opening of the suprapalatal pit. The new taxon cannot be referred to Albanerpeton on the basis of the morphology of the frontals. Wesserpeton currently represents the youngest record of Albanerpetontidae in Britain.
5
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New albanerpetontid amphibians from the Early Cretaceous of Morocco and Middle Jurassic of England

51%
Gardner J. D., Evans S. E., Sigogneau-Russell D.
Acta Palaeontologica Polonica
|
2003
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tom 48
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nr 2
A third albanerpetontid genus, Anoualerpeton gen. nov., is erected for two new species: An. unicussp. nov. (type species) from the Early Cretaceous (Berriasian) of Morocco and An. priscus sp. nov. from the Middle Jurassic (late Bathonian) of England. Anoualerpeton differs from the exclusively Laurasian albanerpetontid genera Albanerpeton (Early Cretaceous– Paleocene, North America; Miocene, Europe) and Celtedens (?Late Jurassic and Early Cretaceous, Europe) in a unique combination of primitive and derived character states of the jaws and azygous frontals. Monophyly of Anoualerpeton is supported by two synapomorphies of the maxilla and dentary (occlusal margin convex in labial outline and teeth strongly heterodont in size anteriorly) that are convergent with an unrelated, relatively derived Late Cretaceous species of Albanerpeton from North America. The two species of Anoualerpeton differ in character states of the premaxilla and azygous frontals. Cladistic analysis of 20 characters scored for ten albanerpetontid taxa postulates Anoualerpeton as the sister−taxon of Albanerpeton + Celtedens. The sister−pair of Albanerpeton + Celtedensis founded on one or, perhaps, two premaxillary synapomorphies. Anoualerpeton unicus documents the only known Gondwanan occurrence for the Albanerpetontidae and provides a minimum age of basal Cretaceous for the establishment of the clade in Africa. Characters of the mandible, vertebrae, and limbs support the interpretation that Ramonellus (Aptian; Israel) is a caudate, not an albanerpetontid.
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