Ligabuesaurus leanzai gen. et sp nov. (Dinosauria, Sauropoda), a new titanosaur from the Lohan Cura Formation (Aptian, Lower Cretaceous) of Neuquén, Patagonia, Argentina

BONAPARTE, JOSÉ F.; GONZÁLEZ RIGA, BERNARDO J.; APESTEGUÍA, SEBASTÍAN

CRETACEOUS RESEARCH (PRINT)

Elsevier Ltd., (imprint Academic Press)

Lugar: Londres; Año: 2006 p. 364 - 376

0195-6671

(Aceptado en el 2005) Ligabuesaurus leanzai gen. et sp. nov. is a new titanosaur (Saurischia, Sauropoda)  from the Early Cretaceous of Neuquén Basin, north Patagonia, Argentina. The fossil remains were found in the upper section of Lohan Cura Formation, regarded as late Aptian  to Albian in age. Remains include an incomplete maxilla with teeth, six dorsal vertebrae and several associated girdle and limb bones. Ligabuesaurus is characterized by: (1) laminar and anteroposteriorly laminar neural spines on posterior cervical and anterior dorsal vertebrae that are rhomboid in shape and wider than vertebral centra; (2) spinoprezygapophyseal laminae in posterior cervical vertebrae forked to form two pairs: the medial laminae contact one another toward the tip of the neural spine, and the lateral pair from the lateral border of the neural spine; (3) dorsoventrally reduced neural arch pedicels in posterior cervical and anterior dorsal vertebrae; and, (4) rudimentary prespinal lamina on posterior cervical and anterior dorsal vertebrae. A preliminary phylogenetic analysis suggest Ligabuesaurus is a basal titanosaur. The development of relatively long forelimbs, with a humerus/femur ratio of 0.9, indicates that this condition is not an exclusive adaptation of the Brachiosauridae.