Vertebrate Fossils from the San José De Gracia Quarry, a New Late
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Boletín de la Sociedad Geológica Mexicana / 72 (1) / 2020 / 1 Vertebrate fossils from the San José de Gracia quarry, a new Late Cretaceous marine fossil site in Puebla, Mexico Fósiles de vertebrados de la cantera San José de Gracia, un nuevo sitio fósil marino del Cretácico Superior en Puebla, México Jesús Alvarado-Ortega1,*, Kleyton M. Cantalice1, Jesús Alberto Díaz-Cruz2, Carlos Castañeda-Posadas3, Valentina Zavaleta-Villareal2 ABSTRACT 1 Instituto de Geología, Universidad Nacional ABSTRACT RESUMEN Autónoma de México, Circuito de la Investigación S/N, Ciudad Universitaria, Alcaldía Coyoacán, CDMX, 04510, Mexico. The San José de Gracia Quarry, located La Cantera San José de Gracia, ubicada within the Municipality of Molcaxac, dentro del Municipio de Molcaxac, al sur del 2 Posgrado en Ciencias Biológicas, Universidad southern Puebla, Mexico, is a new Estado de Puebla, México, es un sitio paleon- Nacional Autónoma de México, Circuito de paleontological site discovered about a tológico descubierto hace cerca de una década. la Investigación S/N, Ciudad Universitaria, Alcaldía Coyoacán, CDMX, 04510, Mexico. decade ago. This paper is the first for- Este trabajo representa la primera contribución mal scientific contribution of this site. científica formal. Esta cantera ocupa una 3 Laboratorio de Paleontología, Facultad de The quarry occupies an area no larger superficie no mayor a las dos hectáreas explo- Ciencias Biológicas, Benemérita Universidad than the two hectares that is exploited tadas con fines comerciales, donde se extraen Autónoma de Puebla. Edificio Bio-1, Ciudad for commercial purposes, where slabs lajas de una secuencia de origen marino, Universitaria, Jardines de San Manuel, Puebla, 72570, Mexico. are extracted from a marine sequence compuesta de margas arcillosas pobremente of cream-brown strata of poorly carbonatados depositadas en estratos paralelos, * Corresponding author: (J. Alvarado-Ortega) carbonated clays, with centimetric de color marrón-crema, cuyo grosor alcanza [email protected] thickness. Although the upper and varios centímetros. A pesar de que los límites, lower limits of this sequence are not superior e inferior, de esta unidad rocosa no known; the characteristic lithology and son conocidos; sus características litológicas y fossil content do not correspond with contenido fósil no corresponden con aquellos de those of the regional geological units las unidades geológicas previamente reportadas previously reported. Although the fossil para esta región. Aunque la asociación fósil association recovered from the San recuperada de la Cantera San José de Gracia José de Gracia Quarry is composed se compone en su mayor parte de restos de mostly of fish remains; it also contains peces; ésta también contiene amonites, belem- To cite this article: ammonites, belemnites, inoceramids, nites, inocerámidos, ostreidos indeterminados, Alvarado-Ortega, J., Cantalice, K. M., Díaz- indeterminate ostreids, reptiles and few reptiles y muy escasos restos de plantas. En Cruz, J. A. Castañeda-Posadas, C., Zavaleta- plant remains. In this work, the first este trabajo se describen los primeros restos de Villareal, V., 2020, Vertebrate fossils from peces fósiles de esta localidad, entre los que se the San José de Gracia quarry, a new Late fossil fish remains from this locality are Cretaceous marine fossil site in Puebla, Mexico: described, including representatives of destacan Enchodus, Laminospondylus y un Boletín de la Sociedad Geológica Mexicana, Enchodus and clupeid both previously clupeido, grupos ya previamente conocidos en 72 (1), A160819. http://dx.doi.org/10.18268/ known from Mexico; as well as the first México; así como el primer registro mexicano BSGM2020v72n1a160819 record of Dercetis and Xenyllion from this de Dercetis y Xenyllion. Aquí, también se country. In addition, a yaguarasaurine reporta el hallazgo deun mosasaurio yaguara- mosasaur is also reported. Based on saurino en México. Con base en su contenido fósil y su litología, se sugiere que los estratos Manuscript received: 08/01/2018 its fossil content and its lithology, the Corrected manuscript received: 28/05/2018 fossil-bearing strata of the San José de fosilíferos de la Cantera San José de Gracia Manuscript accepted: 30/05/2018 Gracia quarry can be possibly referred son referibles posiblemente a la Formación to the Mexcala Formation (More- Mexcala (Cuenca Morelos-Guerrero) y son de los-Guerrero Basin) of Turonian age. edad Turoniana. Peer Review under the responsability of Universidad Nacional Autónoma de México. Keywords: San José de Gracia Palabras clave: Cantera San quarry, Turonian, Puebla, Mex- José de Gracia, edad Turoniana, This is an open access article under the CC BY-NC-SA license (https://creativecommons.org/licenses/by-nc-sa/4.0/) cala Formation, vertebrates. Formación Mexcala, Puebla, vertebrados. Late Cretaceous vertebrates from the San José de Gracia quarry http://dx.doi.org/10.18268/BSGM2020v72n1a160819 Artícle A160819# 2 / Boletín de la Sociedad Geológica Mexicana / 72 (1) / 2020 1. Introduction to discover a peculiar fossiliferous association that we partially report in this contribution (see also In 2006, people of the San José de Gracia town, Alvarado-Ortega et al., 2009, Pulido-González, Municipality of Molcaxac, State of Puebla, central 2011; Romero-García, 2013; Zavaleta-Villareal, INTRODUCTION 2015). Mexico, began to exploit a deposit of sedimentary Fossils from the San José de Gracia quarry are rocks within the limits of their communal property scarce and poorly preserved if they are compared (Figure 1). In this site, herein formally named as with those from the Tlayúa quarry, a Mexican “San José de Gracia quarry”, cream-brown marly emblematic Lagerstätte paleontological site flagstones with reddish veins are extracted. Given located about 10 km south from Molcaxac town its good appearance and resistance, these rocks are (Applegate et al., 2006). For this reason, the work- used to cover floors and walls. The artisanal proce- ers and traders of flagstones extracted in this new dures used during their extraction have allowed us quarry have scorned the scientific and aesthetic Figure 1 Map of San José de Gracia quarry showing the geological formations present in this region of Puebla, Mexico (based on map of Servicio Geológico Mexicano, 2006). Late Cretaceous vertebrates from the San José de Gracia quarry Artícle A160819 http://dx.doi.org/10.18268/BSGM2020v72n1a160819 Boletín de la Sociedad Geológica Mexicana / 72 (1) / 2020 / 3 value of their fossils; this has caused the loss or The San José de Gracia quarry is located 2.5 destruction of a great quantity of San José de km west from the center of homonymous town, Gracia specimens during the extraction and sale within the Municipality of Molcaxac, Puebla, cen- of these rocks. tral Mexico. This site is in the southeastern side In 2007, Messrs. Félix and Sebastián Arangu of the Cacique Stream. Currently, the center of INTRODUCTION thy, traders of flagstones from different sources, the quarry is at the altitude of 1930 m.a.s.l. and inhabitants of Tepexi Rodríguez town (neigh- between the coordinates 18° 39’ 27.25” N and 97 boring town of Molcaxac), and collaborators of ° 52’ 13.94” W. The exploited surface in San José the Tlayúa Paleontological Project, supported by de Gracia quarry extends about 150 m from East the Instituto de Geología, Universidad Nacio- to West and 40 m from North to South (Figure 1). nal Autónoma de México (UNAM), gave some Up to now, a sequence of about 4 m thick fossils from the San José de Gracia to the first of decimetric marly strata has been exploited in author of this work. Thus, in 2008, researchers the San José de Gracia quarry (Figure 2); which of the UNAM and the Benemérita Universidad includes marl layers of clays poorly carbonated, Autónoma de Puebla (BUAP), as well as workers showing normal gradation, and deposited in finely of the San José de Gracia have worked together laminated parallel planes (Figure 2). Although the in order to recover fossils from this new locality, soil covers the geological features around the San with the final goal of preserving and studying José de Gracia Quarry making it impossible to rec- them formally. Currently, about 200 macrofossils ognize the presence of possible faults and contacts from this quarry have been deposited in the sci- with other lithological units; the strata exposed in entific collections of UNAM and BUAP, including this quarry have a strike and dip that suggest the invertebrates (ammonites, belemnites, gastropods, presence of an anticline. At the eastern end of the bivalves, and crabs), vertebrates (fishes and rep- quarry the strike is variable between N50-88°W, tiles), and scarce plant remains. while in the west this geomorphological feature is Figure 2 The San José de Gracia quarry; a) general view of one of the exploited sections in this quarry; b) Details of the San José de Gracia quarry showing the centimetric marl strata. Late Cretaceous vertebrates from the San José de Gracia quarry http://dx.doi.org/10.18268/BSGM2020v72n1a160819 Artícle A160819# 4 / Boletín de la Sociedad Geológica Mexicana / 72 (1) / 2020 close to N90°W. At the same time, the dip in these 3. Results layers is variable between 23-35° S and 23-40° S respectively (Figure 2). As it is noted in the results 3.1. FOSSIL VERTEBRATE ASSEMBLAGE OF SAN JOSÉ of this work, the hitherto known fossil assemblage DE GRACIA MATERIALS AND METHODS / RESULTS of San José de Gracia quarry includes Late Creta- ceous marine vertebrates