Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2019 Neogene Caribbean elasmobranchs: diversity, paleoecology and paleoenvironmental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia) Carrillo-Briceño, Jorge Domingo ; Luz, Zoneibe ; Hendy, Austin ; Kocsis, László ; Aguilera, Orangel ; Vennemann, Torsten Abstract: The Cocinetas Basin is located on the eastern flank of the Guajira Peninsula, northern Colombia (southern Caribbean). During the late Oligocene through the Pliocene, much of the basin was submerged. The extensive deposits in this area suggest a transition from a shallow marine to a fluvio-deltaic system, with a rich record of invertebrate and vertebrate fauna. The elasmobranch assemblages of the early Miocene to the late Pliocene succession in the Cocinetas Basin (Jimol, Castilletes and Ware formations, as well as the Patsúa Valley) are described for the first time. The assemblages include at least 30taxa of sharks (Squaliformes, Pristiophoriformes, Orectolobiformes, Lamniformes and Carcharhiniformes) and batoids (Rhinopristiformes and Myliobatiformes), of which 24 taxa are reported from the Colombian Neogene for the first time. Paleoecological interpretations are based on the feeding ecology and onesti- mates of the paleohydrology (relative salinity, temperature) using stable isotope compositions of oxygen in the bioapatite of shark teeth. The isotopic composition of the studied specimens corroborates pale- oenvironmental settings for the studied units that were previously estimated based on the sedimentology and biology of the taxa. These Neogene elasmobranch assemblages from the Cocinetas Basin provide new insights into the diversity the sharks and rays inhabiting the coastal and estuarine environments of the northwestern margin of South America, both during the existence of the gateway between the Atlantic and Pacific oceans and following its closure. DOI: https://doi.org/10.5194/bg-16-33-2019 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-160997 Journal Article Published Version The following work is licensed under a Creative Commons: Attribution 4.0 International (CC BY 4.0) License. Originally published at: Carrillo-Briceño, Jorge Domingo; Luz, Zoneibe; Hendy, Austin; Kocsis, László; Aguilera, Orangel; Ven- nemann, Torsten (2019). Neogene Caribbean elasmobranchs: diversity, paleoecology and paleoenviron- mental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia). Biogeosciences, 16(1):33-56. DOI: https://doi.org/10.5194/bg-16-33-2019 2 Biogeosciences, 16, 33–56, 2019 https://doi.org/10.5194/bg-16-33-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Neogene Caribbean elasmobranchs: diversity, paleoecology and paleoenvironmental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia) Jorge Domingo Carrillo-Briceño1,2, Zoneibe Luz3, Austin Hendy4, László Kocsis5, Orangel Aguilera6, and Torsten Vennemann3 1Palaeontological Institute and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland 2Smithsonian Tropical Research Institute, Av. Gorgas, Ed. 235, 0843-03092 Balboa, Ancón, Panama 3Institut des Dynamiques de la Surface Terrestre, Université de Lausanne, Rue de la Mouline, 1015 Lausanne, France 4Natural History Museum of Los Angeles County, 900 Exposition Blvd, Los Angeles, California 90007, USA 5Universiti Brunei Darussalam, Faculty of Science, Geology Group, Jalan Tungku, BE 1410, Brunei Darussalam 6Departamento de Biologia Marinha, Instituto de Biologia, Universidade Federal Fluminense, Niterói, 24020-150 Rio de Janeiro, Brazil Correspondence: Zoneibe Luz ([email protected]) Received: 6 June 2018 – Discussion started: 14 June 2018 Revised: 22 October 2018 – Accepted: 30 November 2018 – Published: 8 January 2019 Abstract. The Cocinetas Basin is located on the eastern South America, both during the existence of the gateway be- flank of the Guajira Peninsula, northern Colombia (southern tween the Atlantic and Pacific oceans and following its clo- Caribbean). During the late Oligocene through the Pliocene, sure. much of the basin was submerged. The extensive deposits in this area suggest a transition from a shallow marine to a fluvio-deltaic system, with a rich record of invertebrate 1 Introduction and vertebrate fauna. The elasmobranch assemblages of the early Miocene to the late Pliocene succession in the Cocine- During the Neogene, large areas of the northern margin of tas Basin (Jimol, Castilletes and Ware formations, as well as South America were submerged (see Iturralde-Vinent and the Patsúa Valley) are described for the first time. The assem- MacPhee, 1999) and influenced by the paleoceanographic blages include at least 30 taxa of sharks (Squaliformes, Pris- connection between the Pacific and Atlantic oceans along the tiophoriformes, Orectolobiformes, Lamniformes and Car- Central American Seaway (CAS). The CAS is defined here charhiniformes) and batoids (Rhinopristiformes and Mylio- as a deep oceanic connection between the Pacific and At- batiformes), of which 24 taxa are reported from the Colom- lantic oceans along the tectonic boundary of the Caribbean bian Neogene for the first time. Paleoecological interpreta- and South American plates (Jaramillo et al., 2017). The CAS tions are based on the feeding ecology and on estimates of existed throughout the Cenozoic, but was reduced in width the paleohydrology (relative salinity, temperature) using sta- by the early Miocene (Farris et al., 2011), and the transfer ble isotope compositions of oxygen in the bioapatite of shark of deep water ceased by the late Miocene 12–10 Ma (Montes teeth. The isotopic composition of the studied specimens cor- et al., 2015; Bacon et al., 2015; Jaramillo et al., 2017). Shal- roborates paleoenvironmental settings for the studied units low marine connections between Caribbean and Pacific wa- that were previously estimated based on the sedimentology ters existed until about 4.2–3.5 Ma, when a complete closure and biology of the taxa. These Neogene elasmobranch as- occurred (Coates and Stallard, 2013). The Cocinetas Basin, semblages from the Cocinetas Basin provide new insights located on the eastern flank of the Guajira Peninsula, north- into the diversity the sharks and rays inhabiting the coastal ern Colombia, records a transition in marine and terrestrial and estuarine environments of the northwestern margin of paleoenvironments during this regional change in conditions. Published by Copernicus Publications on behalf of the European Geosciences Union. 34 J. D. Carrillo-Briceño et al.: Neogene Caribbean elasmobranchs from the Guajira Peninsula, Colombia This region presents extensive and well-exposed sedimen- considered as the undifferentiated Jimol and Castilletes For- tary deposits spanning the last 25 Myr (Moreno et al., 2015). mation and are referred to herein as the Patsúa assemblage. The paleoenvironments are characterized by a transition from The samples were collected by JDCB, AH and other shallow marine deposits to a fluvio-deltaic system (Moreno collaborators during several expeditions between 2010 and et al., 2015), with a rich fossil record of invertebrates (Hendy 2014. Large specimens were surface collected and 50 kg et al., 2015) and vertebrates (Aguilera et al., 2013, 2017b; of bulk sediment was collected, sieved and screen washed Moreno et al., 2015; Cadena and Jaramillo, 2015; Amson (mesh sizes: 0.5 and 2 mm) for subsequent picking of smaller et al., 2016; Carrillo-Briceño et al., 2016b; Moreno-Bernal specimens from the localities 290468 (Patsúa assemblage), et al., 2016; Pérez et al., 2016). Ages for many of the fos- 290632 and 390094 (Castilletes Formation). siliferous units in the sequence have been estimated using Sr The Cocinetas Basin elasmobranch specimens (File S4) isotope stratigraphy (see Hendy et al., 2015). are housed in the paleontological collections of the Ma- Neogene marine chondrichthyan faunas from the south- puka Museum of Universidad del Norte (MUN), Barran- ern proto-Caribbean (especially from the northern margin quilla, Colombia. Nomenclature follows Cappetta (2012) of South America) are well known from Venezuela and the and Compagno (2005), with the exception of Rhinopristi- Lesser Antilles (e.g., Leriche, 1938; Casier, 1958, 1966; formes Last et al., 2016, Aetobatidae Agassiz, 1958 (Ta- Aguilera, 2010; Aguilera and Lundberg, 2010; Carrillo- ble 1) and Carcharocles Agassiz, 1838, for which we fol- Briceño et al., 2015b, 2016a, and references therein). But low the nomenclature discussed in Last et al. (2016), White reports on chondrichthyans from the Neogene of Colombia and Naylor (2016) and Ward and Bonavia (2001), respec- are scarce. Previous reports from the Cocinetas Basin include tively. Identifications are based on literature review (e.g., fossil elasmobranchs without taxonomic description (Lock- Santos and Travassos, 1960; Müller, 1999; Purdy et al., 2001; wood, 1965), a checklist of 14 families (Moreno et al., 2015) Cappetta, 1970, 2012; Reinecke et al., 2011, 2014; Voigt and the description of a small assemblage of 13 taxa from and Weber, 2011; Bor et al., 2012; Carrillo-Briceño et al., the early Miocene Uitpa Formation (Carrillo-Briceño et al., 2014; Carrillo-Briceño et al., 2015a, b, 2016b, a; Aguil- 2016b). era et al., 2017a, among others) and comparative analysis A taxonomic list is presented of the