Placidichthys-type locality (Cretaceous of Brazil)

Where: Ceará, Brazil (7.2° S, 40.0° W: paleocoordinates 8.7° S, 8.3° W)

• coordinate based on nearby landmark

When: Romualdo Formation (Santana Group), Late/Upper Aptian (122.5 - 112.0 Ma)

• Romualdo Member, Santana Formation, Lower Cretaceous, Albian

•From Melo et al. 2020: In summary, this integrated study of foraminifera, ostracodes and other microfossil data from the Romualdo Formation indicates that the local Alagoas Stage (Ostracoda Zone RT-011) can now be constrained to the Aptian. Arai and Assine 2020 also support that the Romualdo Formation is entirely Aptian in age.

• member-level stratigraphic resolution

Environment/lithology: marine; nodular lithology not reported

Size class: macrofossils

Collection methods: In 1995 the late Professor Murilo R. Lima gave me an enigmatic and badly preserved fossil nodule from the Santana Formation...The recent discovery of new, better-preserved specimens in the nodules of the Santana Formation and in the Crato Formation, as well as the preparation of two specimens using chemical techniques, allows the description of this new halecomorph.

Primary reference: P. M. Brito. 2000. A new halecomorph with two dorsal fins, Placidichthys bidorsalis n. g., n. sp. (Actinopterygii: Halecomorphi) from the Lower Cretaceous of the Araripe Basin, northeast Brazil. Comptes Rendus de l'Academie des Sciences Paris, Sciences de la Terre et des planètes 331:749-754 [G. Lloyd/G. Lloyd]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 124310: authorized by Graeme Lloyd, entered by Graeme Lloyd on 11.02.2012

Creative Commons license: CC BY (attribution)

Taxonomic list

• Since the last century, a variety of fossil fishes have been recovered from the Lower Cretaceous Araripe Basin of northeast Brazil. These fossils, known by their excellent preservation and diversity include elasmobranchs, halecomorphs, lepisosteids, semionotids, pycnodontids, teleosts, as well as coelacanths
 Ophiopsiformes - Ophiopsiellidae
Placidichthys bidorsalis n. gen. n. sp.
Placidichthys bidorsalis n. gen. n. sp. Brito 2000
MPSC-P 288a and b, MPSC-P 775, PMB-UERJ 300a and b, PMB-UERJ 301