A new Early Cretaceous lamniform shark (Chondrichthyes, Neoselachii)

Kriwet, J. ; Klug, S. ; Canudo, J. I. (Universidad de Zaragoza) ; Cuenca-Bescós, G. (Universidad de Zaragoza)

Resumen: Eoptolamna eccentrolopha gen. et sp. nov. (Chondrichthyes, Lamniformes) from the near coastal upper Barremian Artoles Formation (Early Cretaceous) of Castellote (northwestern Spain) is described on the basis of about 50 isolated teeth. This taxon represents one of the earliest lamniform sharks known to date. We hypothesize that most pre-Aptian lamniforms belong to an ancient group characterized, amongst others, by a very weak gradient monognathic heterodont dental pattern, and by tearing-type dentition. There is a nutritive groove in the lingual root protuberance in juveniles of Eoptolamna, which persists in adults. A single pair of symphysial and a pair of upper intermediate teeth might have been present. Consequently, a new family, Eoptolamnidae, is introduced to include the new form, as well as Protolamna and probably Leptostyrax. The Eoptolamnidae represent an ancient family within Lamniformes. The origin of lamniform sharks remains, however, ambiguous despite recent advances. The new Spanish taxon is widespread in the Barremian of north-eastern Spain, and occurs in a wide range of facies from near-coastal to lake deposits. This lamniform also occurs in the Lower Cretaceous of northern Africa.

Idioma: Inglés

DOI: 10.1111/j.1096-3642.2008.00410.x

Año: 2008

Publicado en: ZOOLOGICAL JOURNAL OF THE LINNEAN SOCIETY 154, 2 (2008), 278-290
ISSN: 0024-4082

Factor impacto JCR: 2.098 (2008)

Categ. JCR: ZOOLOGY rank: 16 / 124 = 0.129 (2008) - Q1 - T1

Financiación: info:eu-repo/grantAgreement/ES/MEC/CGL2004-03393

Tipo y forma: Artículo (PostPrint)

Área (Departamento): Paleontología (Departamento de Ciencias de la Tierra)