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Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela)

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Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela) RESEARCH ARTICLE Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela) Jorge D. Carrillo-Briceño1☯, Erin Maxwell2☯, Orangel A. Aguilera3☯, Rodolfo Sánchez4☯, Marcelo R. Sánchez-Villagra1☯* 1 Paleontological Institute and Museum, University of Zurich, Zürich, Switzerland, 2 Staatliches Museum für Naturkunde, Stuttgart, Germany, 3 Universidade Federal Fluminense, Instituto de Biologia, Campus do Valonguinho, Outeiro SãoJoão Batista, Niterói, Rio de Janeiro, Brasil, 4 Museo Paleontológico de Urumaco, Urumaco, estado Falcón, Venezuela ☯ These authors contributed equally to this work. * [email protected] OPEN ACCESS Abstract Citation: Carrillo-Briceño JD, Maxwell E, Aguilera OA, Sánchez R, Sánchez-Villagra MR (2015) The Urumaco stratigraphic sequence, western Venezuela, preserves a variety of paleoen- Sawfishes and Other Elasmobranch Assemblages vironments that include terrestrial, riverine, lacustrine and marine facies. A wide range of from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela). fossil vertebrates associated with these facies supports the hypothesis of an estuary in that PLoS ONE 10(10): e0139230. doi:10.1371/journal. geographic area connected with a hydrographic system that flowed from western Amazonia pone.0139230 up to the Proto-Caribbean Sea during the Miocene. Here the elasmobranch assemblages Editor: Brian Lee Beatty, New York Institute of of the middle Miocene to middle Pliocene section of the Urumaco sequence (Socorro, Uru- Technology College of Osteopathic Medicine, maco and Codore formations) are described. Based on new findings, we document at least UNITED STATES 21 taxa of the Lamniformes, Carcharhiniformes, Myliobatiformes and Rajiformes, and Received: April 17, 2015 describe a new carcharhiniform species (†Carcharhinus caquetius sp. nov.). Moreover, the Accepted: September 9, 2015 Urumaco Formation has a high number of well-preserved fossil Pristis rostra, for which we Published: October 21, 2015 provide a detailed taxonomic revision, and referral in the context of the global Miocene record of Pristis as well as extant species. Using the habitat preference of the living repre- Copyright: © 2015 Carrillo-Briceño et al. This is an open access article distributed under the terms of the sentatives, we hypothesize that the fossil chondrichthyan assemblages from the Urumaco Creative Commons Attribution License, which permits sequence are evidence for marine shallow waters and estuarine habitats. unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All data has been Introduction collected, prepared and deposited in a public repository by the authors of the article. The current The Caribbean Sea today is environmentally stable and ecologically complex, and it is charac- data is based only in fossil specimens, to which it has terized by high fish diversity [1]. However, the origin of this regional diversity is still somewhat been assigned a specific catalog number. All these problematic. In particular, Neogene chondrichthyan faunas in the Caribbean region are still lit- fossil specimens used to do this publication, are tle known in comparison with other regions as Europe and North America (e.g. [2]), although completely available in a public repository. The – context information for each fossil specimen, is saved several previous works from diverse sedimentary basins exist (e.g. [3 24]) documenting the in an internal data base of the institution. This public paleodiversity of Caribbean faunas before and after the complete closure of the Central Ameri- repository is: the Paleontological Collection of The can Seaway [25]. PLOS ONE | DOI:10.1371/journal.pone.0139230 October 21, 2015 1/30 Elasmobranchs from the Mio-Pliocene of the South Caribbean Alcaldía Bolivariana del Municipio Urumaco and During the Miocene, northern Venezuela was close to the gateway between the Atlantic and Museo Paleontologico de Urumaco, Estado Falcón, Pacific Oceans prior to the definitive closure of the Panamanian Isthmus [25], and so faunal Venezuela. This paleontological collection does not changes in this area provide an important perspective on changes in the Caribbean region as a have a website with a public databank. Access to this paleontological collection is permitted for national or whole. Neogene elasmobranchs from the Miocene of Venezuela have been described previously foreign researchers with previous permission. Access (e.g., [3, 15, 17, 20, 26]), and here we present new data on the elasmobranchs from the Uru- to the collection is obtained by a request directly with maco sequence of northern Venezuela. the curator of paleontology collection and the The Urumaco stratigraphic sequence is composed of seven geological units [27], repre- competent authorities of the Bolivarian Mayoralty sented by diverse paleoenvironment facies including marine, estuarine, riverine, lacustrine and Urumaco, Falcon State, Venezuela. Other fossils referred and illustrated in our article, belong to the terrestrial [27, 28]. Throughout the entire section [27], the lithology varies between more ter- Museo de Ciencias de Caracas (MCNC) and to the restrially influenced beds such as coal seams, and marine-influenced facies including sand- Centro de Investigaciones Antropologicas, stones, limestones and shales. The Urumaco sequence exhibits the most diverse vertebrate Arqueologicas y Paleontologicas de la Universidad fauna from the Neogene of the southern Caribbean, including marine, estuarine, and freshwa- Experimental Francisco de Miranda, Falcón estate, ter fishes, freshwater and marine turtles and crocodilians, terrestrial and aquatic/semiaquatic Venezuela. These institutions have paleontological mammals, and birds (e.g., [29– 32]). The stratigraphic sequence and the associated fauna pro- collections with public access, which is obtained by a request directly with the curator of the collection and vide unequivocal evidence of a marine coastal/estuarine environment, heavily influenced by a the competent authorities. All relevant data necessary complex hydrographic system that flowed from western Amazonia to the proto-Caribbean Sea to replicate the results presented in our article, are during the Miocene (e.g. [27, 31, 33–38]). More than 20 years of paleontological expeditions to available in these paleontological collections of public the Urumaco region made available the collection of elasmobranch assemblages reported here. access referred above. We provide a taxonomic revision of the elasmobranch fauna from the Socorro, Urumaco and Funding: This work was supported by Swiss Codore formations and discuss the paleoenvironmental implications. Importantly, we include National Fund SNF 31003A-149605 to MRSV (www. new shark and ray occurrence data for Tropical America, and we provide a special detailed tax- snf.ch). The funders had no role in study design, data onomic revision of the specimens of Pristis “sawfishes” (Pristidae) found in these assemblages. collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared Material and Methods that no competing interests exist. The fossil elasmobranch fauna from the Urumaco sequence presented here consists of 1234 specimens, and comes from 14 localities of the Socorro, Urumaco and Codore formations (Fig 1, S1 Table, S1 and S2 Appendix). Bulk samples of 10 kg each were collected on the outcrop and the sediment was screen washed using 0.5 mm open mesh. The specimens were sorted using a stereomicroscope. Large specimens were surface-collected from the outcrop. The mate- rial was collected by the authors and other collaborators since 1993 during several expeditions. The specimens are deposited in the paleontological collections of the Alcaldía Bolivariana de Urumaco (AMU-CURS), Centro de Investigaciones Antropológicas, Arqueológicas, Paleonto- lógicas of the Universidad Experimental Francisco de Miranda (CIAAP, UNEFM-PF), and the Museo de Ciencias de Caracas (MCNC). The systematics for fossil and recent taxa follows Compagno [39] and Cappetta [2], with the exception of the extinct genus Carcharocles Jordan and Hannibal [40], whose assignment here has continued the discussion presented by Pimiento et al. [21]; the dental terminology follows Cappetta [2]. Terminology of the internal pristids rostral cavities follows Wueringer et al. [41]. Taxonomic identification included an extensive bibliographical review and comparative studies with fossil and extant specimens from the fol- lowing collections: Fossil vertebrate section of the Museum für Naturkunde in Berlin (MB), Museo Nacional de Historia Natural de Santiago (SGO-PV) in Chile, Museu Paraense Emilio Goeldi (MPEG-V), Brazil; Natural History Museum of Basel (NMB), Switzerland; Palaeontolo- gical Institute and Museum at the University of Zurich (PIMUZ) Switzerland; René Kindli- mann (private collection), Switzerland; Smithsonian Tropical Research Institute, Panama (STRI-PPP-T). We gathered habitat information of all taxa with living representatives using Compagno [42, 43], Compagno et al. [44], Musick et al. [45], Voigt and Weber [46], and the FishBase website (http://www.fishbase.org). The S2 Table is based on Aguilera [19], Aguilera and Lundberg [20], Lundberg et al. [47], Aguilera and Marceniuk [48], and Aguilera et al. [31]. PLOS ONE | DOI:10.1371/journal.pone.0139230 October 21, 2015 2/30 Elasmobranchs
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