Open Paleo

Coahuilasaurus

Longrich et al., 2024 co-wah-WEE-lah-SOR-us

Named after Coahuila, the state in Mexico where the fossils were found, + Greek sauros ('lizard'), meaning 'Coahuila lizard'.

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Coahuilasaurus is an extinct genus of kritosaurin ornithopod dinosaur from the Late Cretaceous (Campanian) Cerro del Pueblo Formation of Coahuila, Mexico. The genus contains a single species, C. lipani, known from the associated tips of the upper and lower jaw and other fragmentary skull bones. It is a large kritosaurin with an estimated body length of 8-9 meters (26-30 ft) and body mass of over 4 metric tons (4.4 short tons).

Diagnosis

  1. Anterodorsal margin of narial process subtly sinusoidal in lateral view, concave anteriorly then weakly convex posteriorly
  2. Narial aperture narrow and slot-like, strongly extended anteroventrally
  3. Posteroventral corner of premaxillary beak strongly angular, anteroventral and posteroventral margins forming approximately a right angle in lateral view
  4. Palatal surface of premaxilla forms horseshoe-shaped ridge projecting far below oral margin, bearing three pairs of massive diamond-shaped denticles
  5. Very large narial flange of premaxilla

Species

Coahuilasaurus lipani Longrich et al., 2024

Type species

Named for the Lépai-Ndé or Lipani, a tribe of Apache Native Americans known from the area of Coahuila, Mexico, where the fossils were found.

Holotype
IGM 6685 , Instituto de Geología, Universidad Nacional Autónoma de México
Material
Partial skull (tips of upper and lower jaw and other fragmentary skull bones)
Horizon
lower Cerro del Pueblo Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Presa San Antonio, Coahuila, Mexico

References

  1. Longrich, N. R.; Ramírez-Velasco, A. A.; Kirkland, J.; Bermúdez Torres, A. E.; Serrano-Brañas, C. I. (2024). Coahuilasaurus lipani, a New Kritosaurin Hadrosaurid from the Upper Campanian Cerro Del Pueblo Formation, Northern Mexico. Diversity 16(9). MDPI AG. doi:10.3390/d16090531

    Gives IGM 6685 as from Presa San Antonio, "25◦27′33′′ N and 101◦42′18′′ W", citing an unlisted 2006 Serrano-Brañas work and a personal communication.

    longrich2024b