References
Reference
Buchy, Marie-Celine (2007) Mesozoic marine reptiles from north-east Mexico: description, systematics, assemblages and palaeobiogeography; PhD, pp.98
Mesozoic marine reptiles from north-east Mexico: description, systematics, assemblages and palaeobiogeography
Principal Author
Marie-Celine Buchy
Header
PhD Thesis
School
(Geologisches Institut, Universität Heidelberg. Staatliches Museum fuÌ�r Naturkunde Karlsruhe
Volume
PhD
Pages
98
Abstract
The result of six years of examination of marine reptiles from north-east Mexico is presented
here. The area yielded specimens from both the Late Jurassic and Late Cretaceous. For a
region where few, undescribed forms were known, the process yielded several new taxa, and a
variety of forms, most of which await preparation, composing rich, hitherto non documented
assemblages.
At present the assemblage of Late Jurassic Mexican Gulf marine reptiles comprises
pliosaurs, thalattosuchians, ichthyosaurs and few plesiosaur remains; no turtle remain was
discovered yet. All proceed from the La Caja / La Casita / La Pimienta Formations
(Kimmeridgian to Tithonian). Except for the ubiquitous ichthyosaur Ophthalmosaurus
icenicus, many specimens, even uncomplete, differ from coeval forms and appear to confirm
the partial isolation of the area that was previously deduced from invertebrates and
microfossils.
During the Cretaceous, the Mexican Gulf connects to both the Western Interior
Seaway and the Atlantic Ocean. Late Cretaceous marine reptiles from north-east Mexico
come from the Late Turonian to early Coniacian Austin Group at Múzquiz, Coahuila, a
promising locality from where few specimens are available for study at present; the
Campanian-Maastrichtian Méndez Formation in Nuevo León yielded few mosasaurid
occurrences; most specimens at present proceed from the Early Turonian Agua Nueva
Formation at Vallecillo, Nuevo León. From Vallecillo is known the only pliosaur remain from
the Mexican Late Cretaceous, a partial tooth attributed to Polyptychodon, and several basal
mosasauroids. These were discovered recently and no taxonomical frame is available at
present, but preservation is usually excellent, including soft parts, and it is expected their
study will greatly increase our knowledge of the group
here. The area yielded specimens from both the Late Jurassic and Late Cretaceous. For a
region where few, undescribed forms were known, the process yielded several new taxa, and a
variety of forms, most of which await preparation, composing rich, hitherto non documented
assemblages.
At present the assemblage of Late Jurassic Mexican Gulf marine reptiles comprises
pliosaurs, thalattosuchians, ichthyosaurs and few plesiosaur remains; no turtle remain was
discovered yet. All proceed from the La Caja / La Casita / La Pimienta Formations
(Kimmeridgian to Tithonian). Except for the ubiquitous ichthyosaur Ophthalmosaurus
icenicus, many specimens, even uncomplete, differ from coeval forms and appear to confirm
the partial isolation of the area that was previously deduced from invertebrates and
microfossils.
During the Cretaceous, the Mexican Gulf connects to both the Western Interior
Seaway and the Atlantic Ocean. Late Cretaceous marine reptiles from north-east Mexico
come from the Late Turonian to early Coniacian Austin Group at Múzquiz, Coahuila, a
promising locality from where few specimens are available for study at present; the
Campanian-Maastrichtian Méndez Formation in Nuevo León yielded few mosasaurid
occurrences; most specimens at present proceed from the Early Turonian Agua Nueva
Formation at Vallecillo, Nuevo León. From Vallecillo is known the only pliosaur remain from
the Mexican Late Cretaceous, a partial tooth attributed to Polyptychodon, and several basal
mosasauroids. These were discovered recently and no taxonomical frame is available at
present, but preservation is usually excellent, including soft parts, and it is expected their
study will greatly increase our knowledge of the group
Language
English