A Turonian pycnodontiform fish from the San José de Gracia Quarry, Puebla, Mexico
Un pez pycnodontiforme turoniano de la Cantera San José de Gracia, Puebla, México
Stephanie Pacheco Ordaz1, Alvaro Reyes-López2, Jesús Alvarado-Ortega3,*
1 Posgrado en Ciencias Químico Biológicas, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Unidad Profesional Lázaro Cárdenas. Prolongación de Carpio y Plan de Ayala S/N, Col. Santo Tomás, Alcaldía Miguel Hidalgo, Ciudad de México, 11340 México.
2 Independent Researcher. Bachillerato General Sor Juana Inés de la Cruz, Chalchicomula de Sesma, Puebla, México.
3 Instituto de Geología, Universidad Nacional Autónoma de México. Circuito de la Investigación S/N, Ciudad Universitaria, Alcaldía Coyoacán, Ciudad de México, 04510 México.
* Corresponding author: (J. Alvarado-Ortega) This email address is being protected from spambots. You need JavaScript enabled to view it.
How to cite this article:
Pacheco-Ordaz, S., Reyes-López, A., Alvarado-Ortega, J., 2025, A Turonian pycnodontiform fish from the San José de Gracia Quarry, Puebla, Mexico: Boletín de la Sociedad Geológica Mexicana, 77(1), A241224. http://dx.doi.org/10.18268/BSGM2025v77n1a241224
Manuscript received: February 8, 2024; Corrected manuscript received: March 22, 2024; Manuscript accepted: May 13, 2024.
ABSTRACT
We report the presence of pycnodontiform fishes in the Turonian marine deposits of the Mexcala Formation, exposed in the San José de Gracia Quarry in the Municipality of Molcaxac, Puebla, central Mexico. This report includes a complete, articulated, and superficially poorly preserved specimen. This specimen has some peculiar osteological features for example: the supraorbital skull region is peculiarly prominent and rounded; its neural and hemal arcocentra have long, sharp lateral flanges that interlock with those of the contiguous arcocentra, forming tight and complex zigzagging suture; and its vomerine and pre-articular teeth have a flat and concave medial surface and lateral edges with aligned serrations and cusps. These along with other features are sufficient to allow us to conclusively identify this fish as a member of the order Pycnodontiformes, suborder Pycnodontoidei, family Pycnodontidae, and subfamily Nursalliinae. Comparison of the species within the subfamily allows us to identify the specimen of San José de Gracia as Paranursallia gutturosa, previously only known from northwestern Africa. In Addition, similar fossil fishes of the Agua Nueva Formation, previously recovered at sites such as the Vallecillo quarries in Nuevo León, Huehuetla in Puebla, and Xilitla in San Luis Potosí, suggest that these represent the same species.