A new Late Cretaceous (Campanian–Maastrichtian) amiid (Halecomorphi: Actinopterygii) from the Fruitland Formation, San Juan Basin, New Mexico

Abstract

Amia? chauliodeia, a new amiid fish from the Late Cretaceous Fruitland Formation of the San Juan Basin, New Mexico, is described from material that includes vertebral centra, elements of the mandibular arch, dermal skull roof, palatal complex, hyoid arch, pectoral girdle, branchial apparatus, ribs, and both pelvic basipterygia. The new form differs from previously described amiiforms in the length of the dentary tooth row, in the anterior thickness of the dentary, and in the apparent lack of internal sensory canals in the dentary and angular. The New Mexico amiid also retains a primitive metapterygoid. Although the new form shares several features in common with the Late Cretaceous amiid Melvius thomasi described by Bryant (1987), it is unquestionably distinct from this form. Material from the Fruitland and Kirtland Formations of New Mexico referred by Bryant (1987) to M. thomasi is now included within Amia? chauliodeia.