The Pastos Bons Formation is a Late Jurassic (Oxfordian to Kimmeridgian) geologic formation of the Parnaíba Basin in Maranhão, northeastern Brazil. The formation forms part of the sag phase of the basin. It overlies the Sardinha Formation and is overlain by the Mosquito Formation.[1] The fluvial to lacustrine sandstones and shales have provided fossils of a coelacanth fish, Parnaibaia maranhaoensis and a paralligatorid named after the formation, Batrachomimus pastosbonensis.

Pastos Bons Formation
Stratigraphic range: Oxfordian-Kimmeridgian
~161–151 Ma
Geologic map of the Parnaíba Basin with the Jurassic in red
TypeGeological formation
UnderliesMosquitos Formation
OverliesSardinha Formation
Lithology
PrimarySandstone
OtherShale
Location
Coordinates6°06′S 44°42′W / 6.1°S 44.7°W / -6.1; -44.7
Approximate paleocoordinates2°24′S 12°06′W / 2.4°S 12.1°W / -2.4; -12.1
RegionMaranhão
Country Brazil
ExtentParnaíba Basin
Type section
Named forPastos Bons
Pastos Bons Formation is located in Brazil
Pastos Bons Formation
Pastos Bons Formation
Pastos Bons Formation (Brazil)

Fossil content

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The following fossils were reported from the formation:[2]

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Crocodylomorphs

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Crocodylomorphs of the Pasto Bons Formation
Genus Species Location Stratigraphic position Material Notes Images
Batrachomimus[3] B. pastosbonensis A paralligatorid neosuchian.

Fish

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Fishes of the Pasto Bons Formation
Genus Species Location Stratigraphic position Material Notes Images
Lophionotus[4] L. parnaibensis A semionotid fish.
Parnaibaia[5] P. maranhaoensis A mawsoniid coelacanth.
Quasimodichthys[6] Q. piauhyensis A semionotiform fish.

Plants

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Plants of the Pasto Bons Formation
Genus Species Location Stratigraphic position Material Notes Images
Araucariaceae Indet.

See also

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References

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  1. ^ De Castro et al., 2016, p.532
  2. ^ Pastos Bons Formation at Fossilworks.org
  3. ^ Felipe C. Montefeltro; Hans C. E. Larsson; Marco A. G. de França; Max C. Langer (2013). "A new neosuchian with Asian affinities from the Jurassic of northeastern Brazil". Naturwissenschaften. 100 (9): 835–841. Bibcode:2013NW....100..835M. doi:10.1007/s00114-013-1083-9. PMID 23893176. S2CID 11705304.
  4. ^ Gallo, V.; de Paiva, H. C. L.; Petra, R.; Brito, P. (2022). "Lophionotus parnaibensis, sp. nov. (Semionotiformes, Semionotidae) in the Upper Jurassic of the Parnaíba Basin, Northeastern Brazil". Journal of Vertebrate Paleontology. 41 (4). e1994983. doi:10.1080/02724634.2021.1994983. S2CID 246164511.
  5. ^ Yabumoto, 2007
  6. ^ Hanna Carolina Lins de Paiva; Valéria Gallo (2018). "Quasimodichthys gen. nov. (Neopterygii: Semionotiformes): A morphological and ontogenetic study". Journal of South American Earth Sciences. 88: 132–143. Bibcode:2018JSAES..88..132P. doi:10.1016/j.jsames.2018.08.010. S2CID 134986658.

Bibliography

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