Producción CyT

Tribute to Charles Darwin to Bernissart iguanodons: New perspectives on Vertebrate Evolution and Early Cretaceous Ecosytems. - Iguanodon-like footprints from the Enciso Group (Aptian, Lower Cretaceous) of La Rioja (Cameros Basin, Spain).

Congreso

Autoría:

DÍAZ MARTÍNEZ, IGNACIO ; Félix Pérez Lorente ; Xabier Pereda Suberbiola ; José Ignacio Canudo

Fecha:

2009

Editorial y Lugar de Edición:

naturalsciences

Resumen *

Large ornithopod (Iguanodon-like) footprints are relatively abundant in the Enciso Group of the Cameros Basin (La Rioja, Spain). Casanovas & Santafé (1971 and subsequent works) referred these tracks to Iguanodon or to “iguanodontid” ornithopods. A revision of the La Rioja footprints allows providing information about the palaeobiodiversity of the trackmakers. Moratalla (1993) distinguished three morphotypes of Iguanodon-like footprints, which are present in La Magdalena (Préjano), Peña Untura (San Román de Cameros) and Valdeté (Préjano) sites. In this work a fourth morphotype (Hadrosaurichnoides) from La Era del Peladillo site (Igea) is also considered. All of them are known in the Enciso Group (Aptian). Morphotype 1. “Brachyiguanodonipus”. It represents graviportal, mesaxonic and tridactyl footprints. Wider than long, with a rhomboidal pad per digit, and other sub-rounded and wide in the heel. Short digits, as long as wide, with a rounded to blunt distal ending. Notch present in the proximal part of the digits II and IV. Morphotype 2. “Iguanodonipus”. This morphotype grouped mesaxonic and tridactyl footprints with similar length and width, with rounded and wide hell. Sometimes the posterior part of the heel is narrow and elongated, probably for the metatarsal support. The digits are longer than wide, sub-triangular, with sub-acute distal ends. The notch (if present) is not well marked. Morphotype 3. Indeterminate ichnotaxon. This morphotype grouped mesaxonic and tridactyl footprints. They are longer than wide, with a pad per digit and other in the heel. The digits are longer than wide, with a blunt distal ending. This indeterminate taxon present well marked notchs and short and rounded heel. Morphotype 4. “Hadrosaurichnoides”. It represents to mesaxonic and tridactyl footprints with approximately as long as wide, with a pad per digit and other in the heel. The digits are short and wide, with a blunt distal ending. “Hadrosaurichnoides” present interdigital web and short and rounded heel, without notch. The shape differences in the footprints from the Lower Cretaceous Cameros Basin suggest that four different ichnotaxons are represented. The morphology of the footprints 1, 3 and 4 is coherent with that of Iguanodon or closely related large iguanodontoids. On the basis of the morphotype 2, the presence of more basal ornithopods (basal ankylopollexians?) cannot be rejected.Iguanodon-like) footprints are relatively abundant in the Enciso Group of the Cameros Basin (La Rioja, Spain). Casanovas & Santafé (1971 and subsequent works) referred these tracks to Iguanodon or to “iguanodontid” ornithopods. A revision of the La Rioja footprints allows providing information about the palaeobiodiversity of the trackmakers. Moratalla (1993) distinguished three morphotypes of Iguanodon-like footprints, which are present in La Magdalena (Préjano), Peña Untura (San Román de Cameros) and Valdeté (Préjano) sites. In this work a fourth morphotype (Hadrosaurichnoides) from La Era del Peladillo site (Igea) is also considered. All of them are known in the Enciso Group (Aptian). Morphotype 1. “Brachyiguanodonipus”. It represents graviportal, mesaxonic and tridactyl footprints. Wider than long, with a rhomboidal pad per digit, and other sub-rounded and wide in the heel. Short digits, as long as wide, with a rounded to blunt distal ending. Notch present in the proximal part of the digits II and IV. Morphotype 2. “Iguanodonipus”. This morphotype grouped mesaxonic and tridactyl footprints with similar length and width, with rounded and wide hell. Sometimes the posterior part of the heel is narrow and elongated, probably for the metatarsal support. The digits are longer than wide, sub-triangular, with sub-acute distal ends. The notch (if present) is not well marked. Morphotype 3. Indeterminate ichnotaxon. This morphotype grouped mesaxonic and tridactyl footprints. They are longer than wide, with a pad per digit and other in the heel. The digits are longer than wide, with a blunt distal ending. This indeterminate taxon present well marked notchs and short and rounded heel. Morphotype 4. “Hadrosaurichnoides”. It represents to mesaxonic and tridactyl footprints with approximately as long as wide, with a pad per digit and other in the heel. The digits are short and wide, with a blunt distal ending. “Hadrosaurichnoides” present interdigital web and short and rounded heel, without notch. The shape differences in the footprints from the Lower Cretaceous Cameros Basin suggest that four different ichnotaxons are represented. The morphology of the footprints 1, 3 and 4 is coherent with that of Iguanodon or closely related large iguanodontoids. On the basis of the morphotype 2, the presence of more basal ornithopods (basal ankylopollexians?) cannot be rejected. Información suministrada por el agente en SIGEVA

Palabras Clave

CAMEROS BASINLA RIOJAFOOTPRINTSIGUANODON-LIKE