PBDB Collection

Cerro del Castillo, Trelew: Aquitanian - Burdigalian, Argentina

List of taxa

Where & when

Geology

Taphonomy & methods

Metadata & references

Taxonomic list

Mammalia - Cetacea

	Phoberodon arctirostris n. gen., n. sp. Cabrera 1926		1 specimen

	Prosqualodon australis n. gen., n. sp. Lydekker 1894	Gaetán et al. 2019	2 specimens
	(1 measurement)
Mammalia - Cetacea - Balaenidae

	Morenocetus parvus n. gen., n. sp. Cabrera 1926		2 specimens
Mammalia - Cetacea - Balaenopteridae

	Plesiocetus dyticus n. sp. Cabrera 1926
	MDLP 5-13
Mammalia - Cetacea

	Cetotherium moreni n. sp. Lydekker 1894	Lydekker 1894	1 specimen
Reptilia

	Chubutodyptes biloculata n. gen., n. sp. Simpson 1970	Simpson 1970	1 specimen

	Palaeospheniscus patagonicus n. sp. Moreno and Mercerat 1891	Moreno and Mercerat 1891

	Palaeospheniscus menzbieri n. sp. Moreno and Mercerat 1891	Moreno and Mercerat 1891

	Palaeospheniscus affinis Ameghino 1905	Simpson 1946

	Palaeospheniscus interruptus Ameghino 1905	Simpson 1946

	Palaeospheniscus bergi n. sp. Moreno and Mercerat 1891	Moreno and Mercerat 1891

	Palaeospheniscus rothi Ameghino 1905	Simpson 1946

	Palaeospheniscus gracilis Ameghino 1899	Simpson 1946

	Palaeospheniscus medianus Ameghino 1905	Simpson 1946

	Neculus rothi Ameghino 1905	Simpson 1946
Reptilia - Spheniscidae

	Palaeospheniscus antarcticus n. gen., n. sp. Moreno and Mercerat 1891	Simpson 1946

	Palaeospheniscus robustus Ameghino 1894	Simpson 1946

	Treleudytes crassus (Ameghino 1905)	Simpson 1946
see common names

Country:	Argentina	State/province:	Chubut
Coordinates:	43.3° South, 65.3° West (view map)
Paleocoordinates:	42.9° South, 61.8° West (Wright 2013)
Basis of coordinate:	estimated from map

Period:	Neogene	Epoch:	Miocene
Stage:	Aquitanian - Burdigalian	10 m.y. bin:	Cenozoic 5
Key time interval:	Aquitanian - Burdigalian
Age range of interval:	23.04 - 15.98 m.y. ago
Age estimate:	19.8 to 18.2 Ma (other)

Formation:	Gaiman
Stratigraphic resolution:	formation
Stratigraphy comments: formacion patagonica marina; early Miocene date form Fordyce (2002); In the area of the type locality of M. parvus, the lower part of Gaiman Formation overlies the continental Sarmiento Formation, which contains a mammal fauna correlating with the Colhuehuapian South American Land Mammal Age [51,52]. The latter was dated to 19.8-20.9 Ma, based on 40Ar/39Ar dating [53], thus providing a maximum age of ca. 20 Ma (earliest Burdigalian) for the lower part of the Gaiman Formation in this area. Since virtually all vertebrate material recovered so far originated from the lowermost levels of the Gaiman Formation, close to its contact with the Sarmiento Formation (Cozzuol 2010, pers. comm.), the age of Morenocetus is here assumed to be early Burdigalian. (Fordyce & Marx, 2013) Both MLP 5-11 and 5-11 were originally reported to have come from the Patagonian Marine Formation [40]. The latter corresponds to the partially correlated Monte León and Gaiman formations, exposed in Santa Cruz (e.g. Garn Bajo de San Juan) and the lower Chubut river valley near Trelew (e.g. at Bryn Gwyn/ Loma Blanca), respectively [42]. In the area around Trelew, the lower part of Gaiman Formation overlies the continental Sarmiento Formation, which contains a mammal fauna correlating with the Colhuehuapian South American Land Mammal Age [43, 45]. The latter has been 40Ar/39Ar dated to 20.9– 19.8 Ma [46], thus providing a maximum age of 19.8 Ma (earliest Burdigalian) for the lower part of the Gaiman Formation in this area. Since virtually all vertebrate material recovered so far originated from the lowermost levels of the Gaiman Formation, close to its contact with the Sarmiento Formation [Cozzuol 2010, pers. comm.], an early Burdigalian age (19.8–18.2 Ma) is here assumed for M. parvus. (Marx & Fordyce, 2015)

Primary lithology:	argillaceous sandstone
Includes fossils?	Y
Lithology description: a mixture of sand and clay, including a stratum of sand capped by volcanic sand
Environment:	shallow subtidal indet.
Geology comments: The holotype of A. moreni was found in “a mixture of sand and clay, including a stratum of sand capped by volcanic sand.” ([39]:1). The original description further explained that ”an apparently contemporaneous bed in Santa Cruz, also containing cetacean bones, has yielded oysters of an extinct species (Ostrea patagonica), and one skull from Chubut has one of the same oysters attached” [39: 1-2]. MLP 5-14 was later discovered at the same locality, described as “Castillo, frente a Trelew, Chubut” [40: 369], and reported to have come from the Patagonian Marine Formation (“formación patagónica marina”, [40: 364]). The Patagonian Marine Formation corresponds to the partially correlated Monte León and Gaiman formations, exposed in Santa Cruz (e.g. Garn Bajo de San Juan) and the lower Chubut river valley near Trelew (e.g. at Bryn Gwyn/ Loma Blanca), respectively [42]. The Gaiman Formation consists of layers of marine sandstones and mudstones, as well as tuffs and tuffaceous sandstones. In addition, the lower part also contains occasional thin layers of Ostrea and bones of marine vertebrates [43]. Thus, the portion of the Gaiman Formation exposed near Trelew provides a likely match for the unit that yielded A. moreni [39, 40, 44]. 11 In the area around Trelew, the lower part of Gaiman Formation overlies the continental Sarmiento Formation, which contains a mammal fauna correlating with the Colhuehuapian South American Land Mammal Age [43, 45]. The latter has been 40Ar/39Ar dated to 20.9– 19.8 Ma [46], thus providing a maximum age of 19.8 Ma (earliest Burdigalian) for the lower part of the Gaiman Formation in this area. Since virtually all vertebrate material recovered so far originated from the lowermost levels of the Gaiman Formation, close to its contact with the Sarmiento Formation [Cozzuol 2010, pers. comm.], an early Burdigalian age (19.8–18.2 Ma) is here assumed for A. moreni. (Marx & Fordyce, 2015) Shows a shallow, storm-dominated marine environment with significant sea level oscillations.

Modes of preservation:	body,original phosphate
Size of fossils:	macrofossils

Database number:	47303
Authorizer:	M. Uhen	Enterer:	M. Uhen
Modifier:	M. Uhen	Research group:	vertebrate
Created:	2005-02-22 11:25:32	Last modified:	2025-02-24 15:20:29
Access level:	the public	Released:	2005-02-22 11:25:32
Creative Commons license:	CC0

37374		M. R. Buono, M. T. Dozo, and M. A. Cozzuol. 2010. Balaenidae (Mammalia, Cetacea, Mysticeti) del Mioceno de Patagonia: antecedentes, nuevos registros y proyecciones. Ameghiniana 46(4 Sup.):66R [M. Uhen/M. Uhen]
61705		C. M. Gaetán, M. R. Buono, and L. C. Gaetano. 2019. Prosqualodon australis (Cetacea: Odontoceti) from the Early Miocene of Patagonia, Argentina: Redescription and phylogenetic analysis. Ameghiniana 56(1):1-27 [M. Uhen/B. Shipps/M. Uhen]
91089		C. M. Gaetán, M. R. Buono, Y. Tanaka, N. D. Farroni, and V. N. Milano. 2025. Echoes from the Miocene: tracing the anatomy and phylogeny of Prosqualodon australis (Cetacea: Odontoceti). Journal of Systematic Palaeontology 23(1):2455753 [M. Uhen/M. Uhen]
12338		R. Lydekker. 1894. Cetacean skulls from Patagonia. Anales del Museo de la Plata II:1-13 [M. Uhen/M. Uhen/M. Uhen]
55050		F. G. Marx and R. E. Fordyce. 2015. Baleen boom and bust: a synthesis of mysticete phylogeny, diversity and disparity. Royal Society Open Science 2:140434 [M. Uhen/M. Uhen]
29788		F. P. Moreno and A. Mercerat. 1891. Catálogo de los pájaros fósiles de la República Argentina conservados en el Museo de La Plata [Catalogue of the fossil birds from the Argentine Republic housed in the Museo de La Plata]. Anales del Museo de La Plata. Paleontología Argentina 1:7-71 [M. Uhen/M. Uhen/M. Carrano]
25128		G. G. Simpson. 1946. Fossil Penguins. Bulletin of the American Museum of Natural History 87(1):1-100 [M. Uhen/M. Uhen]
25175		G. G. Simpson. 1970. Miocene penguins from Victoria, Australia, and Chubut, Argentina. Memoirs of the National Museum of Victoria 31:17-24 [M. Uhen/M. Uhen]