[D] Ajkaceratops kozmai [sG] [T]
Describer
Osi, Butler & Weishampel 2010
Time
Cretaceous Late Santonian
Classification
Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia [Coronosauria]
Diet
Herbivore
Fossilsite
Czehbánya Formation, Iharku´ t, Veszpre´m County, Bakony Mountains, Transdanubian Range, western Hungary
Info
Abstract: Ceratopsians (horned dinosaurs) represent a highly diverse and abundant radiation of non-avian dinosaurs known primarily from the Cretaceous period (65–145 million years ago). This radiation has been considered to be geographically limited to Asia and western NorthAmerica with only controversial remains reported from other continents. Here we describe new ceratopsian cranial material from the Late Cretaceous of Iharku´ t, Hungary, from a coronosaurian ceratopsian, Ajkaceratops kozmai. Ajkaceratops is most similar to ‘bagaceratopsids’ such as Bagaceratops and Magnirostris, previously known only from Late Cretaceous east Asia. The new material unambiguously demonstrates that ceratopsians occupied Late Cretaceous Europe and, when considered with the recent discovery of possible leptoceratopsid teeth from Sweden, indicates that the clade may have reached Europe on at least two independent occasions. European Late Cretaceous dinosaur faunas have been characterized as consisting of a mix of endemic ‘relictual’ taxa and ‘Gondwanan’ taxa, with typical Asian and North American groups largely absent. Ajkaceratops demonstrates that this prevailing biogeographical hypothesis is overly simplified and requires reassessment. Iharku´ t was part of the western Tethyan archipelago, a tectonically complex series of island chains between Africa and Europe, and the occurrence of a coronosaurian ceratopsian in this locality may represent an early Late Cretaceous ‘island-hopping’ dispersal across the Tethys Ocean.
Holotype. MTM V2009.192.1, fused premaxillae and rostral bones with fragments of the maxillae; housed in the collections of the Hungarian Natural History Museum, Budapest, Hungary.
Etymology. Ajka: the town of Ajka, which is close to the type locality; ceratops (Greek): horned face. (Intended pronunciation: oi-ka-seratops.) The species is named in honour of Ka´roly Kozma.
Referred material. MTM V2009.193.1, V2009.194.1, V2009.195.1, V2009.196.1: four predentary bones.
Horizon and locality. Csehba´nya Formation (Upper Cretaceous, Santonian13), Iharku´ t, Veszpre´m County, Bakony Mountains, Transdanubian Range, western Hungary. Iharku´ t has previously yielded a typical European Late Cretaceous dinosaur assemblage of endemic rhabdodontid ornithopods and basal nodosaurid ankylosaurs. Diagnosis. Differs from all other coronosaurian ceratopsians in the following character combination (* indicates autapomorphies): (1) large oval accessory fenestra are present between the premaxilla and maxilla, with the nasal excluded from its margin; (2*) the part of the premaxilla ventral to the external naris and the accessory fenestra is dorsoventrally shallow relative to its rostrocaudal length; (3*) the caudolateral process of the premaxilla is curved along its length becoming nearly horizontal caudally; (4*) the buccal margins of the predentary are sharp and not bevelled.
Osi, Butler & Weishampel 2010
Time
Cretaceous Late Santonian
Classification
Ornithischia Genasauria Cerapoda Marginocephalia Ceratopia Neoceratopia [Coronosauria]
Diet
Herbivore
Fossilsite
Czehbánya Formation, Iharku´ t, Veszpre´m County, Bakony Mountains, Transdanubian Range, western Hungary
Info
Abstract: Ceratopsians (horned dinosaurs) represent a highly diverse and abundant radiation of non-avian dinosaurs known primarily from the Cretaceous period (65–145 million years ago). This radiation has been considered to be geographically limited to Asia and western NorthAmerica with only controversial remains reported from other continents. Here we describe new ceratopsian cranial material from the Late Cretaceous of Iharku´ t, Hungary, from a coronosaurian ceratopsian, Ajkaceratops kozmai. Ajkaceratops is most similar to ‘bagaceratopsids’ such as Bagaceratops and Magnirostris, previously known only from Late Cretaceous east Asia. The new material unambiguously demonstrates that ceratopsians occupied Late Cretaceous Europe and, when considered with the recent discovery of possible leptoceratopsid teeth from Sweden, indicates that the clade may have reached Europe on at least two independent occasions. European Late Cretaceous dinosaur faunas have been characterized as consisting of a mix of endemic ‘relictual’ taxa and ‘Gondwanan’ taxa, with typical Asian and North American groups largely absent. Ajkaceratops demonstrates that this prevailing biogeographical hypothesis is overly simplified and requires reassessment. Iharku´ t was part of the western Tethyan archipelago, a tectonically complex series of island chains between Africa and Europe, and the occurrence of a coronosaurian ceratopsian in this locality may represent an early Late Cretaceous ‘island-hopping’ dispersal across the Tethys Ocean.
Holotype. MTM V2009.192.1, fused premaxillae and rostral bones with fragments of the maxillae; housed in the collections of the Hungarian Natural History Museum, Budapest, Hungary.
Etymology. Ajka: the town of Ajka, which is close to the type locality; ceratops (Greek): horned face. (Intended pronunciation: oi-ka-seratops.) The species is named in honour of Ka´roly Kozma.
Referred material. MTM V2009.193.1, V2009.194.1, V2009.195.1, V2009.196.1: four predentary bones.
Horizon and locality. Csehba´nya Formation (Upper Cretaceous, Santonian13), Iharku´ t, Veszpre´m County, Bakony Mountains, Transdanubian Range, western Hungary. Iharku´ t has previously yielded a typical European Late Cretaceous dinosaur assemblage of endemic rhabdodontid ornithopods and basal nodosaurid ankylosaurs. Diagnosis. Differs from all other coronosaurian ceratopsians in the following character combination (* indicates autapomorphies): (1) large oval accessory fenestra are present between the premaxilla and maxilla, with the nasal excluded from its margin; (2*) the part of the premaxilla ventral to the external naris and the accessory fenestra is dorsoventrally shallow relative to its rostrocaudal length; (3*) the caudolateral process of the premaxilla is curved along its length becoming nearly horizontal caudally; (4*) the buccal margins of the predentary are sharp and not bevelled.