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Onslow Bay study area. (A) Inset map of the Atlantic Coastal Plain of the United States showing the Onslow Bay study region (star) and maximum extent of marine inundation during the Middle Miocene %18 Ma (red line) and sea-level lowstand during the Last Glacial Maximum %18 Ka (black line). (B) Map of the Cape Fear Region of southwestern Onslow Bay showing bathymetric contours and seismic stratigraphic sediment divisions beneath Onslow Bay modified from Snyder et al. (1982) and Snyder et al. (1993). Letters a, b and c show locations of the shallower (a), intermediate (b) and deeper (c) lag deposit localities discussed in this study (after Maisch, Becker, and Chamberlain 2018, Figure 1).
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The shallow continental shelf in the Cape Fear Region of southwestern Onslow Bay, North Carolina, contains lag deposits with an abundance of megatoothed shark teeth belonging to Otodus megalodon (Agassiz 1835) and Otodus chubutensis (Ameghino 1906) that derive from the Pliocene Yorktown and Miocene Pungo River formations, respectively. These teeth...
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... paleontology: Otodus megalodon and Otodus chubutensis A detailed taxonomic study of lamniform and carcharhiniform sharks from the shallower, intermediate and deeper lag deposit localities identified in Figure 1 was recently reported by Maisch, Becker, and Chamberlain (2018). According to these authors, the largest and most abundant shark teeth occurring on the submerged Onslow Bay shelf are those belonging to the megatoothed sharks, O. megalodon and O. chubutensis. ...
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... teeth belonging to O. megalodon and O. chubutensis described in this report were recovered from three lag deposit localities adjacent to Frying Pan Shoals in southwestern Onslow Bay, North Carolina ( Figure 1). These three localities occur at approximately 30 km (25 m deep), 40 km (30 m deep) and 60 km (35 m deep) from the present-day shoreline ( Figure 1). ...
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... teeth belonging to O. megalodon and O. chubutensis described in this report were recovered from three lag deposit localities adjacent to Frying Pan Shoals in southwestern Onslow Bay, North Carolina ( Figure 1). These three localities occur at approximately 30 km (25 m deep), 40 km (30 m deep) and 60 km (35 m deep) from the present-day shoreline ( Figure 1). Deposits found at these submerged localities include gray-blue or brown-gray clay and gray-tan sandy limestone that have been previously identified as either the early-late Pliocene (Zanclean-Piacenzian) Yorktown Formation or late early Miocene (Aquitanian-Burdigalian) Pungo River Formation ( Roberts and Pierce 1967;Cleary and Pilkey 1968;Blackwelder, MacIntyre, and Pilkey 1982;Crowson et al. 1994;Schmid 1996;Riggs et al. 1996Riggs et al. , 1998Renaud et al. 1997;Riggs 1982, 1990;Maisch, Becker, and Chamberlain 2018). ...
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... megatoothed shark teeth belonging to O. megalodon and O. chubutensis were collected over a seven-year period during multiple SCUBA dives out of Carolina Beach Inlet at each of the submerged lag deposit localities identified in Figure 1. Specimens were excavated from the unconsolidated lag deposits or from bulk sampled sediment brought to the surface. ...
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... the shallower locality, O. megalodon and O. chubutensis teeth co-occur on the seafloor directly overlying an eroded surface of the Pungo River Formation (Figures 1-4). O. megalodon teeth contain extensive, multiphase Gastrochaenolites macroborings on both lingual and labial tooth surfaces, while such macroborings are rarely observed on O. chubutensis teeth (Table 2). ...
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... lag deposit contains an abundance of Meg. teeth that infrequently exhibit bioerosion or taphonomic wear suggesting they have recently been exhumed as a result of large storm events Formation (Pliocene: Zanclean-Piacenzian) are exposed on the seafloor (Figures 1-4). The frequency of Gastrochaenolites macroborings decreases dramatically between these two deposits and indicates that O. megalodon teeth from the intermediate locality have been exhumed and reburied multiple times since they were shed (Tables 1 and 2). ...
Citations
... Broad areas of both the crown and the root of GAMPS-01072 are covered by whitish encrustations, including tiny polychaete calcareous tubes, which testify to a rather prolonged exposure at the sea bottom. Differing from the otodontid teeth from the submerged shelf off North Carolina, U.S.A. (Maisch IV et al. 2020), no macroborings excavate either the root or the crown of GAMPS-01072. At the find site, the seafloor is a hardground comprised of fossiliferous calcarenites that have been correlated with similar rocks cropping out along the coastline of the nearby mainland (Mazzanti et al. 2001). ...
The white shark, Carcharodon carcharias (Linnaeus, 1758), is a fairly uncommon and somewhat enigmatic inhabitant of the present-day Mediterranean Basin. In this broad region, fossil teeth of C. carcharias are known from the lower Pliocene onwards, but definite Pleistocene records concentrate in a few southern Italian localities along the Ionian and Tyrrhenian coasts. Here, we report on new and historical specimens of C. carcharias from the Quaternary of Tuscany (central Italy), which provide valuable data on the post-Pliocene history of white sharks in the southern Ligurian Sea (a north-western Mediterranean quarter where white sharks are currently rare). Some of these finds come from mollusc-bearing sands that were quarried at Torre del Lago (Lucca Province). Originally regarded as “Versilian” (latest Pleistocene to Holocene) in age, these largely immature white shark teeth date back to the mid-Holocene (Northgrippian, roughly corresponding to the last phases of the Holocene Climate Optimum). A new dental specimen of C. carcharias originates from Lower Pleistocene (Calabrian, ?Emilian) sediments cropping out at Montalto, near Fauglia (Pisa Province). Among many other fossils, the Montalto locality has also yielded a monk seal calcaneum, thus hinting at a possible predator-prey relationship between the shark and the pinniped. An additional record comes from the Meloria Shoals, off Leghorn. It likely derives from the shallow-marine, Upper Pleistocene (Tyrrhenian) fossiliferous deposits that are locally exposed at the seafloor. Together with previous Pleistocene finds from southern Italy, these Tuscan fossils highlight the ecological plasticity of the Mediterranean white sharks, which persisted through the fairly massive climatic and environmental perturbations that characterised the Quaternary Period without obvious connections with their adjacent Atlantic conspecifics.
... These results clearly suggest that these nuclei are fish teeth. Indeed, biogenic calcium phosphate (BCP), mainly comprising P and Ca and known to include fish teeth, is ubiquitously found in seafloor sediments (e.g., [22,23]). The three Type I-O nuclei were markedly different. ...
Ferromanganese nodule nuclei are considered crucial to the formation and distribution of nodules. However, because it is difficult and time-consuming to study ferromanganese nodule nuclei, few studies have been performed, despite the large number of samples. Here, we analyzed the nuclei of 934 ferromanganese nodules from the abyssal seafloor around Minamitorishima Island (western North Pacific Ocean) using X-ray computed tomography (CT). Based on the CT number distribution (describing X-ray absorption in Hounsfield units, HU), we classified the nuclei as Type I (>1800 HU) or Type II (<1800 HU). Additionally, some Type I nuclei had characteristic conical shapes (Type I-C) distinct from the shapes of other nuclei (Type I-O). Based on the chemical compositions determined by microfocus X-ray fluorescence analyses of selected samples, we identified Type I-C, I-O, and II nuclei as fish teeth, hard rocks (volcanic rock, ironstone, or phosphorite), and sediments, respectively. These nucleus types were observed in sufficient quantities at all dive sites that we conclude them to be typical of nodule nuclei in the study area. Fish-tooth nuclei were the rarest at all sites, whereas sediment nuclei dominated at most sites, suggesting their significance for understanding the origin of ferromanganese nodules. Hard-rock nuclei dominated at only three sites and probably originated from seamounts.
... Cappetta (2012) further extended the use of Otodus for the entire megatoothed shark lineage, given that their fossil record suggests anagenetic-type evolution where most of them represent different chronospecies (Shimada et al. 2017). This hypothesis is now shared by many researchers (Bor et al. 2012;Andrianavalona et al. 2015;Trif et al. 2016;Boessenecker et al. 2019;Jambura et al. 2019;Shimada 2019;Cooper et al. 2020;Herraiz et al. 2020;Maisch et al. 2020;Ballell & Ferrón 2021;Perez et al. 2021). ...
In the second issue of Samuel Morton's "Synopsis of the organic remains of the Cretaceous group of the united States" published in June 1835, several otodontid shark teeth from Cenozoic formations of New Jersey are named with authorship of Louis Agassiz and meet the conditions of availability of the international Code of Zoological nomenclature. it has gone largely unnoticed that some of these names were introduced in this work before their publication in Agassiz's masterpiece "Recherches sur les poissons fossiles". The specimens presented by Morton were kept in the John Price Wetherill (1794-1853) collection that found its way into the paleontological collection of the Academy of natural Sciences of Drexel University, Philadelphia, where most of them have been rediscovered. These teeth are part of the type series upon which Agassiz introduced Lamna obliqua Agassiz in Morton, 1835, Lamna lanceolata Agassiz in Morton, 1835, Carcharias lanceolatus Agassiz in Morton, 1835, Carcharias megalotis Agassiz, 1835 and Carcharias polygurus Agassiz in Morton, 1835, all of these species being referred to the genus Otodus in the present work. in order to secure the nomenclatural stability of the Otodontidae, it is established that Otodus lanceolatus is a junior synonym of Otodus obliquus, that "Carcharias" lanceolatus belongs to the genus Otodus Agassiz, 1838 and is invalid as a junior secondary homonym of Otodus lanceolatus, that Otodus megalotis is a junior synonym of Otodus auriculatus (Blainville, 1818), and that Otodus polygurus (Otodus polygyrus being an incorrect subsequent spelling) is a junior synonym of Otodus megalodon (Agassiz, 1835). Furthermore, it is shown that the date of publication of Otodus obliquus (Agassiz in Morton, 1835) is 1835 and not 1838 as previously thought.
... Linear regressions applied for the possible anatomical positions (L1 to L4) of MMDA-101 taken from Shimada (2002) where Y is the total length of the body (TL) and X is crown height (CH). Average value of TL for all positions as well as the formula of Gottfried et al. (1996) case, we can mention the findings from Miocene-Pliocene beds from North America (Purdy et al., 2001;Maisch et al., 2020). Fossil terrestrial megamammals (such as armored xenarthrans and giant sloths) are frequently found along the Bonaerian seashore, with most remains coming from Upper Pleistocene beds at the marine platform . ...
Carcharocles megalodon is considered a macropredatory shark that inhabited the seas around the world from middle Miocene to late Pliocene. In Argentina, it has only been formally recorded at two localities. Here, we report the first record for this taxon in the Buenos Aires Province. This occurrence is based on an isolated tooth recovered on the beach at the Punta Médanos locality, which lacks clear stratigraphic context. Based on the regional geology, the specimen probably came from Pliocene beds. Its size indicates that it probably belongs to a juvenile individual. Keywords: Carcharocles megalodon, macropredatory shark, fossil teeth, Mar de Ajó.
... Although microbial alteration of bones (bioerosion) is known from aquatic environments, equivalent alteration in teeth has only rarely been reported. Documented bioerosion patterns of dental tissues include endolithic macro-and microborings of fossil teeth and small tubules within dentine represented by traces and holes of endolithic bivalves, clionaid sponges, serpulid worms, and routes of microbial intrusion 9,10 . Here we review the fossil record of bioerosion and document for the first time in situ bacteria within the highly mineralized and organic-poor tooth enameloid of an extinct deep-water shark. ...
Alteration of organic remains during the transition from the bio-to lithosphere is affected strongly by biotic processes of microbes influencing the potential of dead matter to become fossilized or vanish ultimately. If fossilized, bones, cartilage, and tooth dentine often display traces of bioerosion caused by destructive microbes. The causal agents, however, usually remain ambiguous. Here we present a new type of tissue alteration in fossil deep-sea shark teeth with in situ preservation of the responsible organisms embedded in a delicate filmy substance identified as extrapolymeric matter. The invading microorganisms are arranged in nest-or chain-like patterns between fluorapatite bundles of the superficial enameloid. Chemical analysis of the bacteriomorph structures indicates replacement by a phyllosilicate, which enabled in situ preservation. Our results imply that bacteria invaded the hypermineralized tissue for harvesting intra-crystalline bound organic matter, which provided nutrient supply in a nutrient depleted deep-marine environment they inhabited. We document here for the first time in situ bacteria preservation in tooth enameloid, one of the hardest mineralized tissues developed by animals. This unambiguously verifies that microbes also colonize highly mineralized dental capping tissues with only minor organic content when nutrients are scarce as in deep-marine environments.
... Although microbial alteration of bones (bioerosion) is known from aquatic environments, equivalent alteration in teeth has only rarely been reported. Documented bioerosion patterns of dental tissues include endolithic macro-and microborings of fossil teeth and small tubules within dentine represented by traces and holes of endolithic bivalves, clionaid sponges, serpulid worms, and routes of microbial intrusion 9,10 . Here we review the fossil record of bioerosion and document for the first time in situ bacteria within the highly mineralized and organic-poor tooth enameloid of an extinct deep-water shark. ...
Alteration of organic remains during the transition from the bio- to lithosphere is afected strongly by biotic processes of microbes infuencing the potential of dead matter to become fossilized or vanish ultimately. If fossilized, bones, cartilage, and tooth dentine often display traces of bioerosion caused by destructive microbes. The causal agents, however, usually remain ambiguous. Here we present a new type of tissue alteration in fossil deep-sea shark teeth with in situ preservation of the responsible organisms embedded in a delicate flmy substance identifed as extrapolymeric matter. The invading microorganisms are arranged in nest- or chain-like patterns between fuorapatite bundles of the superfcial enameloid. Chemical analysis of the bacteriomorph structures indicates replacement by a phyllosilicate, which enabled in situ preservation. Our results imply that bacteria invaded the hypermineralized tissue for harvesting intra-crystalline bound organic matter, which provided nutrient supply in a nutrient depleted deep-marine environment they inhabited. We document here for the frst time in situ bacteria preservation in tooth enameloid, one of the hardest mineralized tissues developed by animals. This unambiguously verifes that microbes also colonize highly mineralized dental capping tissues with only minor organic content when nutrients are scarce as in deep-marine environments.
Restos dentales de seláceos fueron recolectados en la caverna Gabinarraca, en Venado de San Carlos. Estos fósiles se encontraron en litofacies tipo grainstone, asociados a ambientes de estuario lagunar carbonatado característicos de la Formación Venado de edad Mioceno Superior-Plioceno. Entre los restos de tiburones recuperados destacan ejemplares juveniles de Carcharo-cles megalodon asociado a ambientes sublitorales y ambientes de aguas salobres. El hallazgo de estos restos permite evidenciar que especies como el Carcharocles megalodon utilizaron las aguas someras del Mioceno donde actualmente se localiza Venado de San Carlos como zona de crianza.
ABSTRACT: Remains of selachians have been collected at the Gabinarraca cave. These fossils were found in grainstone-type lithofacies from the Upper Miocene carbonated lagoon and estuarine sediments of the Venado Formation. Among the sharks remains are notorious the juvenile specimens of Carcharocles megalodon associated to a shallow marine and brackish waters environments. The discovery of these remains shows that species such as Carcharocles megalodon used the shallow waters of the Miocene where Venado de San Carlos is currently located as a breeding area.
Trophic position is a fundamental characteristic of animals, yet it is unknown in many extinct species. In this study, we ground-truth the 15N/14N ratio of enameloid-bound organic matter (δ15NEB) as a trophic level proxy by comparison to dentin collagen δ15N and apply this method to the fossil record to reconstruct the trophic level of the megatooth sharks (genus Otodus). These sharks evolved in the Cenozoic, culminating in Otodus megalodon, a shark with a maximum body size of more than 15 m, which went extinct 3.5 million years ago. Very high δ15NEB values (22.9 ± 4.4‰) of O. megalodon from the Miocene and Pliocene show that it occupied a higher trophic level than is known for any marine species, extinct or extant. δ15NEB also indicates a dietary shift in sharks of the megatooth lineage as they evolved toward the gigantic O. megalodon, with the highest trophic level apparently reached earlier than peak size.
The Otodus genus and its species have been recorded in Southern Central America since the Eocene epoch, its remains are associated with calcareous or clastic sediments typical of sublitoral or inner neritic environments. One of these geological formations is Santa Teresa Fm. with a Middle Miocene to Lower Pliocene age range, outcropping in the Pacific margin and the elevated parts at the southern end of the Nicoya Peninsula, where a series of finds of Otodus (Megaselachus) chubutensis and Otodus (Megaselachus) megalodon had been previously reported. Over several decades, dental remains associated with Otodus genus have been recorded at Southern Nicoya Peninsula, fortuitous finds, some of them without direct geological context. However, the locations given by the people who made the findings, allow us to establish with some degree of certainty the sedimentary units from which the samples came, allowing us to increase the knowledge of the abundance and diversity of the fossil record of these giant sharks.
RESUMEN: El género Otodus y sus especies han sido registradas en el sur de América Central desde el Eoceno, sus restos están asociadas a sedimentos calcáreos o clásticos propios de ambientes sublitorales y neríticos internos. Una de esas formaciones geoló-gicas es la Fm. Santa Teresa con un rango de edad Mioceno Medio-Plioceno Inferior, aflorante en la margen pacífica y las partes altas del extremo sur de la Península de Nicoya, donde se habían reportado y descrito con anterioridad una serie de hallazgos de Otodus (Megaselachus) chubutensis y Otodus (Megaselachus) megalodon. A lo largo de varias décadas, restos dentales asociados al género Otodus se han venido registrando en el Sur de la península de Nicoya, algunos constituyen hallazgos fortuitos y algunos incluso fuera de contexto geológico. Sin embargo, las ubicaciones dadas por las personas que hicieron los hallazgos, permiten establecer con algún grado de certeza las unidades sedimentarias de donde las muestras procedían, permitiéndonos incrementar el conocimiento, abundancia y diversidad del registro fósil de estos tiburones gigantes. Palabras clave: Otodus (Megaselachus) chubutensis, Otodus (Megaselachus) megalodon, Formación Santa Teresa, Mioceno Medio-Plioceno Inferior, Costa Rica. ABSTRACT: The Otodus genus and its species have been recorded in Southern Central America since the Eocene epoch, its remains are associated with calcareous or clastic sediments typical of sublitoral or inner neritic environments. One of these geological formations is Santa Teresa Fm. with a Middle Miocene to Lower Pliocene age range, outcropping in the Pacific margin and the elevated parts at the southern end of the Nicoya Peninsula, where a series of finds of Otodus (Megaselachus) chubutensis and Otodus (Me-gaselachus) megalodon had been previously reported. Over several decades, dental remains associated with Otodus genus have been recorded at Southern Nicoya Peninsula, fortuitous finds, some of them without direct geological context. However, the locations given by the people who made the findings, allow us to establish with some degree of certainty the sedimentary units from which the samples came, allowing us to increase the knowledge of the abundance and diversity of the fossil record of these giant sharks.
