Castilletes Formation Research Articles

A fossil fish assemblage from the middle Miocene of the Cocinetas Basin, northern Colombia

AbstractFreshwater fossil fish faunas have long been used to infer past drainage connections, given that they are bounded by physical freshwater barriers. Here we study a middle Miocene (15.0–15.5 Ma) freshwater fish fossil fauna (Makaraipao) from the Castilletes Formation in northern Colombia, nowadays west of the Andes. We record the presence of lungfishes (Lepidosiren), pacus (Mylossoma and Piaractus), armoured catfishes (Callichthyidae), and red‐tail catfishes (Phractocephalus). Extant members of all those groups (except the Callichthyidae, due to lack of taxonomic resolution) are found in Amazonian faunas east of the Andes and are absent from faunas west of the Andes, indicating that the riverine systems of the Guajira Peninsula were connected to Amazonia during the middle Miocene. The similarity of La Venta (west of the Andes) and Rio Acre (east of the Andes) fish faunas during the late Miocene further indicates that the northern Andean uplift was not a complete barrier at least until c. 11 Ma. However, there is a continental‐wide structuring of the Miocene fish faunas that is also found in the extant faunas, suggesting that other factors such as ecological conditions, in addition to the uplift of the Andes, have shaped the biogeographic evolution of South American fish faunas.

Isotope sclerochronology indicates enhanced seasonal precipitation in northern South America (Colombia) during the Mid-Miocene Climatic Optimum

Abstract During the Mid-Miocene Climatic Optimum (MMCO, 14.7–17.3 Ma), global temperatures were warmer than present, and similar to predicted temperatures for the coming century. Limited paleoclimate data exist from the tropics during this period, despite its potential as an analog for future climate conditions. This study presents new subannual stable isotope data (δ18O and δ13C) from a large population of Miocene Turritella gastropods from the Jimol and Castilletes Formations of the Guajira Peninsula, Colombia. Turritellids are aragonitic marine mollusks that live in shallow coastal waters, and their rapid growth rates allow for high-resolution subannual records. We compare these fossils to modern Turritella gastropods from multiple tropical localities to reconstruct subannual climate conditions. The seasonal range in δ18O in the modern shells correlates with the seasonal variance of local precipitation, once temperature seasonality is accounted for. The Miocene fossils show larger (in some cases >2‰) seasonal variation in δ18O than modern Turritella from the same location, suggesting increased seasonality of precipitation in Miocene northern Colombia relative to today. We propose that this increased seasonality of precipitation was due to a more northerly position of the Intertropical Convergence Zone during the mid-Miocene. The resulting wet Miocene paleoenvironment is in stark contrast to semiarid conditions on the Guajira Peninsula today, indicating that this area of tropical South America has undergone a drastic environmental change since the Miocene.

Reporte del hallazgo de restos de Hilarcotherium sp. (Mammalia, Astrapotheria) y de material asociado en una nueva localidad fosilífera del valle inferior del Magdalena, ciénaga de Zapatosa, Cesar, Colombia

En abril de 2018 el Museo Geológico “José Royo y Gómez” recibió el reporte del hallazgo de material paleontológico en cercanías del corregimiento de La Mata, en el municipio de Chimichagua (Cesar), a orillas de la ciénaga de Zapatosa. El material recolectado por pobladores del lugar incluía un gran diente de caimán (Purussaurus), restos de tortugas (Podocnemididae?) y matamata (Chelus), y un fragmento de maxilar de Hilarcotherium sp. (Mammalia, Astrapotheria), conocido previamente por los hallazgos de la especie tipo Hilarcotherium castanedaii (Vallejo-Pareja, et al., 2015) en los estratos del Grupo Honda (Formación La Victoria) en el municipio de Purificación, Tolima, y de Hilarcotherium miyou (Carrillo, et al., 2018) de la Formación Castilletes, al sureste de la península de La Guajira. Además, este informe constituye el primer registro de rocas continentales del Mioceno en esta región del país. © 2018. Acad. Colomb. Cienc. Ex. Fis. Nat.

The Neogene Record of Northern South American Native Ungulates

South America was isolated during most of the Cenozoic, and it was home to an endemic fauna. The South American Native Ungulates (SANUs) exhibited high taxonomical, morphological, and ecological diversity and were widely distributed on the continent. However, most SANU fossil records come from high latitudes. This sampling bias challenges the study of their diversity dynamics and biogeography during important tectonic and biotic events, such as the Great American Biotic Interchange, the faunal exchange between North and South America after the formation of the Isthmus of Panama. We describe new SANU remains from the Neogene of the Cocinetas (northern Colombia) and Falcon (northwestern Venezuela) Basins. In the Cocinetas Basin, the middle Miocene fauna of the Castilletes Formation includes Hilarcotherium miyou sp. nov. (Astrapotheriidae), cf. Huilatherium (Leontiniidae), and Lambdaconus cf. L. colombianus (Proterotheriidae). The late Pliocene fauna of the Ware Formation includes a Toxodontinae indet. and the putative oldest record of Camelidae in South America. In the Falcon Basin, the Pliocene/Pleistocene faunas of the Codore and San Gregorio Formations include Falcontoxodon aguilerai gen. et sp. nov. and Proterotheriidae indet. We provide a phylogenetic analysis for Astrapotheriidae and Toxodontidae. The new data document a low-latitude provinciality within some SANU clades (e.g., Astrapotheriidae, Leontiniidae) during the middle Miocene. This contrasts with the wide latitudinal distribution of clades of other mammals recorded in the fauna, including the sparassodont Lycopsis padillai, the sloth Hyperleptus?, and the proterotheriid Lambdaconus cf. L. colombianus. The Pliocene/Pleistocene tropical faunas from northern South America are characterized by the predominance of native taxa despite their proximity to the Isthmus of Panama (fully emerged by that time). Only one North American ungulate herbivore immigrant is present, a cf. Camelidae indet. The Pliocene and early Pleistocene faunas suggest that environmental changes and biotic interactions affected the diversity dynamics and biogeographic patterns of SANUs during the Great American Biotic Interchange.

Fossil Crocodilians from the High Guajira Peninsula of Colombia: Neogene faunal change in northernmost South America

ABSTRACTThe La Guajira Peninsula, Colombia, has a continuous vertebrate fossil record that includes both the late early–early middle Miocene and the Pliocene. Crocodilians from the early to early middle Miocene Jimol and Castilletes formations include gavialoids, recovered from both coastal and shallow marine deposits, and caimanines representing early records of the specialized caimanine taxa Purussaurus and Mourasuchus. Crocodyloid specimens from the Pliocene Ware Formation are assigned to Crocodylus and represent one of the oldest occurrences of the genus in the New World. Records from the La Guajira Peninsula suggest that diverse crocodilian assemblages were already established by the late early Miocene, including several widely distributed lineages that persisted for several million years. Crocodylus is a recent immigrant to South America that occupied habitats left vacant by the extinction of several crocodilian lineages.Citation for this article: Moreno-Bernal, J. W., J. Head, and C. A. Jaramillo. 2016. Fossil crocodilians from the High Guajira Peninsula of Colombia: Neogene faunal change in northernmost South America. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1110586.

Insights into the Neotropics prior to the Great American Biotic Interchange: new evidence of mammalian predators from the Miocene of Northern Colombia

ABSTRACTA new species of Sparassodonta (Mammalia, Metatheria), Lycopsis padillai, sp. nov., is described on the basis of a partial left maxilla with M1–M4 and fragments of lacrimal and jugal. The material comes from the early to early middle Miocene Castilletes Formation, La Guajira Peninsula, Colombia. This specimen represents the northernmost record of a fossil metatherian in South America and integrates a highly diverse vertebrate association, recently discovered in the north of Colombia. The La Guajira specimen is referred to the genus Lycopsis, as supported by the results of our phylogenetic analysis. This analysis also demonstrates that species of Lycopsis (L. torresi, L. longirostrus, L. viverensis, and L. padillai) constitute a monophyletic group and are placed as the basal taxon of Borhyaenoidea. Lycopsis padillai is a large-sized sparassodont with a body mass of about 22 kg. The presence of Lycopsis from La Guajira extends the geographical distribution of the genus to the entire South America, representing the sparassodont with the widest latitudinal distribution.http://zoobank.org/urn:lsid:zoobank.org:pub:B3127EDAB4BB-4972-81B9-4447CC44EE79SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Suarez, C., A. M. Forasiepi, F. J. Goin, and C. Jaramillo. 2015. Insights into the Neotropics prior to the Great American Biotic Interchange: new evidence of mammalian predators from the Miocene of Northern Colombia. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2015.1029581.

Neogene molluscs, shallow marine paleoenvironments, and chronostratigraphy of the Guajira Peninsula, Colombia

The Neogene sedimentary fill of the Cocinetas Basin in northern Colombia preserves a rich record of marine invertebrates and can be analyzed in the context of a high-resolution stratigraphy and excellent chronostratigraphy. Molluscan fossils are highly diverse and often well preserved, offering a window into the rapidly changing paleoenvironments and biogeography of northern South America during parts of the Early to Middle Miocene and latest Pliocene to Pleistocene. Before the evolutionary and biogeographic implications of these fossils can be understood, however, their associated depositional environments and geologic ages must be determined. Here, we present preliminary results from paleoenvironmental, biostratigraphic, and strontium isotope chronostratigraphic analyses of sediments and fossils from the Uitpa, Jimol, Castilletes, and Ware formations found in Cocinetas Basin. The basal unit in the Neogene succession, the Uitpa Formation, comprises mudstones redeposited sandstones and molluscs typical of bathyal to outer shelf environments at its base. It is a shallowing-up sequence and is conformable with the overlying Jimol Formation, which comprises coarse-grained lithic calcarenite, coquina, and mudstone that represent a regressive–transgressive–regressive sequence. This sequence includes foreshore and transition zone through lower inner shelf environments, but generally poorly preserved invertebrate assemblages. The conformably overlying Castilletes Formation contains a varied suite of depositional environments with better-developed shell beds and thicker successions of intervening siltstone. A significant unconformity exists between the Castilletes Formation and the overlying Ware Formation, which represents a deltaic to coastal shoreface deposition environment, rich in shallow marine molluscs from a variety of ecotopes. Biostratigraphic assessment and strontium isotopic results from the Jimol and Castilletes formations indicate that these units contain fossils of latest Early Miocene through Middle Miocene age, while those of the Ware are approximately Late Pliocene in age. These results help to place the shallow marine assemblages of Cocinetas Basin into a wider geologic context that aids our understanding of how these faunas relate to the broader evolutionary and biogeographic history of the southern Caribbean during the Neogene. Additionally, the isotope dating and paleoecology of this fauna help to place co-occurring terrestrial and aquatic vertebrate assemblages into a local paleoenvironmental and chronostratigraphic framework.

Preface: La Guajira, Colombia: a new window into the Cenozoic neotropical biodiversity and the Great American Biotic Interchange

Over the past four years, we have conducted extensive fieldwork in the Cocinetas Basin of La Guajira Peninsula, including geological mapping, stratigraphic descriptions, and exhaustive paleontological collection of plants, microfossils, and marine and terrestrial invertebrates and vertebrates. Moreno et al. (Swiss J Paleontol 134: 1–39, 2015) provide an overview of these efforts, including a revised Neogene stratigraphy for Cocinetas Basin and redefined (Jimol and Castilletes formations) and newly named (Ware Formation) lithostratigraphic units. Hendy et al. (Swiss J Paleontol 134, 2015) utilize the extensive invertebrate fossil record of the basin to develop paleoenvironmental interpretations and a chronostratigraphic framework buttressed by 87Sr/86Sr isotopic analyses and biostratigraphy. This geological exploration highlights the tremendously diverse and important fossil assemblages throughout the Jimol, Castilletes and Ware formations. These new fossil data will be of great value for future paleobiogeographic, paleogeographic, paleooceanographic and paleoenvironmental interpretations. Already, the faunal and floral fossil record of Cocinetas Basin indicates that once the humid ecosystem of the Neogene underwent drastic climatic changes over the last two million years.

Revised stratigraphy of Neogene strata in the Cocinetas Basin, La Guajira, Colombia

The Cocinetas Basin of Colombia provides a valuable window into the geological and paleontological history of northern South America during the Neogene. Two major findings provide new insights into the Neogene history of this Cocinetas Basin: (1) a formal re-description of the Jimol and Castilletes formations, including a revised contact; and (2) the description of a new lithostratigraphic unit, the Ware Formation (Late Pliocene). We conducted extensive fieldwork to develop a basin-scale stratigraphy, made exhaustive paleontological collections, and performed 87Sr/86Sr geochronology to document the transition from the fully marine environment of the Jimol Formation (ca. 17.9–16.7 Ma) to the fluvio-deltaic environment of the Castilletes (ca. 16.7–14.2 Ma) and Ware (ca. 3.5–2.8 Ma) formations. We also describe evidence for short-term periodic changes in depositional environments in the Jimol and Castilletes formations. The marine invertebrate fauna of the Jimol and Castilletes formations are among the richest yet recorded from Colombia during the Neogene. The Castilletes and Ware formations have also yielded diverse and biogeographically significant fossil vertebrate assemblages. The revised lithostratigraphy and chronostratigraphy presented here provides the necessary background information to explore the complete evolutionary and biogeographic significance of the excellent fossil record of the Cocinetas Basin.

Early to Middle Miocene Turtles from the Northernmost Tip of South America: Giant Testudinids, Chelids, and Podocnemidids from the Castilletes Formation, Colombia

Abstract. Here we describe the northernmost South American record of fossil turtles from the late early Miocene to early middle Miocene of the Castilletes Formation, on the Alta Guajira Peninsula, Cocinetas basin, Colombia. Turtles in the lower segment of the Castilletes Formation (c. 16.33 Ma) are pleurodires or side-necked turtles belonging to Chelus colombiana Wood, Chelus sp., and Podocnemididae incertae sedis, and cryptodires or hidden-necked turtles attributed to Chelonoidis sp., all of them characterized by the large size of their shells, 1 meter or more total length. The middle segment of the formation (c. 14 Ma) contains specimens of Podocnemididae incertae sedis and Chelonoidis sp. The turtle fauna from Castilletes share taxa with faunas from La Venta (middle—late Miocene of Colombia), Urumaco, and Western Amazonia (late Miocene from Venezuela, Brazil, and Peru); all of these records indicate a wider geographical distribution for podocnemidids, chelids, and testudinids of tropical South America ...

Ariid sea catfishes from the coeval Pirabas (Northeastern Brazil), Cantaure, Castillo (Northwestern Venezuela), and Castilletes (North Colombia) formations (early Miocene), with description of three new species

Ariidae catfish are described from the early Miocene Pirabas Formation in northeastern Brazil, Cantaure and Castillo formations in northwestern Venezuela, and Castilletes Formation in North Colombia. A skull from the Pirabas Formation is described as Cathorops goeldii, n. sp. and an otolith is identified as Cathorops sp. The otoliths from Cantaure, Castillo and Castilletes formations are described as Cantarius nolfi n. sp. and Bagre protocaribbeanus n. sp. These coeval lithostratigraphic units reflect the Proto-Caribbean conditions and the shallow water tropical palaeoenvironment during the Miocene, particularly associated with marine coastal lagoon and estuarine influence.