Montañita/Olón: Chattian, Ecuador

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Reptilia - Testudines
Chelonioidea (informal Pan-Cheloniidae) indet. (Baur 1893)
Cadena et al. 2018 1 specimen
Mammalia - Cetacea
Urkudelphis chawpipacha n. gen., n. sp. Tanaka et al. 2017
1 specimen
Chondrichthyes - Lamniformes - Otodontidae
Carcharocles angustidens (Agassiz 1835)
recombined as Otodus (Carcharocles) angustidens
see common names

Geography
Country:Ecuador State/province:Santa Elena
Coordinates: 1.8° South, 80.8° West (view map)
Paleocoordinates:3.6° South, 75.5° West
Time
Period:Paleogene Epoch:Oligocene
Stage:Chattian 10 m.y. bin:Cenozoic 4
Key time interval:Chattian
Age range of interval:28.10000 - 23.03000 m.y. ago
Stratigraphy
Formation:Dos Bocas Member:Zapotal
Stratigraphy comments: Here, we provisionally identify the source horizon for MO-1 as the Zapotal Member of the Dos Bocas Formation, with names following Whittaker [25]. More study is needed to establish the proper terminology of the coastal strata outside, but closely-related to, the Progreso Basin. We did not find foraminiferans that might be used for dating. The presence of Carcharocles angustidens is consistent with a late Oligocene age suggested by Bristow. Elsewhere, in the East Pisco basin of Peru, C. angustidens is not reported from the vertebrate-bearing Chattian to Burdigalian Chilcatay Formation, in which the richest vertebrate-bearing horizon is Burdiga- lian [29–31]), but occurs in older units (M. Urbina and A. Altamirano (Departamento de Paleontolog ́ıa de Vertebrados, Museo de Historia Natural, Universidad Nacional Mayor de San Marcos), personal communication, fide T.J. DeVries (Burke Museum of Natural History and Culture, University of Washington, Seattle)). Thus, the age of MO-1 is consistent with a probable Chattian age (24 to 26 Ma), as shown by Bristow [23] (his Fig 3, Zapotal Member of Tosagua Formation).
Lithology and environment
Primary lithology: sandstone
Includes fossils?Y
Lithology description: composed of a moder- ately-sorted, fine to medium sandstone with angular quartzo-feldspathic clasts. Conspicuous rounded green grains are probably glauconite, but berthierine cannot be dismissed. The matrix is micritic and volcanogenic, possibly bentonitic. Bedding is massive to indistinct
Environment:coastal indet.
Geology comments: quiet setting; estuarine or mid-shelf
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Reason for describing collection:general faunal/floral analysis
Metadata
Database number:190942
Authorizer:M. Uhen, P. Holroyd Enterer:M. Uhen, P. Holroyd
Modifier:P. Holroyd Research group:vertebrate
Created:2017-12-26 11:37:08 Last modified:2018-04-19 20:07:42
Access level:the public Released:2017-12-26 11:37:08
Creative Commons license:CC BY
Reference information

Primary reference:

64255. Y. Tanaka, J. Abella, Gl Aguirre-Fernández, M. Gregori, and R. E. Fordyce. 2017. A new tropical Oligocene dolphin from Montañita/Oló, Santa Elena, Ecuador. PLoS One 12(12):e0188380 [M. Uhen/M. Uhen]

Secondary references:

65080 E. Cadena, J. Abella, and M. Gregori. 2018. The first Oligocene sea turtle (Pan-Cheloniidae) record of South America. PeerJ 6(e4554):1-10 [P. Holroyd/P. Holroyd]