Revealing new trilobites from the early Devonian alto garças sub-basin, Brazil

ABSTRACT

The composition of the trilobite fauna from the Devonian Paraná Basin in Brazil is still not fully elucidated. Although rich literature on the southern portion of this basin, the northwestern part has been poorly explored. In this study, we reveal new taxa and provide a comprehensive taxonomic composition of malvinoxhosan trilobites collected from the PragianEmsian sediments of Alto Garças Subbasin, Brazil. We report Burmeisteria notica, Metacryphaeus australis, Pennaia pauliana, Calmonia signifer and Kozlowskiaspis subseciva, well known elements from the southern portion of the Paraná Basin. Metacryphaeus meloi, unprecedented in the Paraná Basin, reveals itself here in the oldest biostratigraphic position in relation to other specimens reported from the Cabeças Formation (Frasnian-Famennian, Parnaíba Basin). We reveal a new species of Bainella, here described as Bainella (Belenops) sulmatogrossensis sp. nov. We discuss the biostratigraphic position of components of this fauna and their correlation with other Devonian units. Taking all together, our work provides a new picture about the trilobite taxonomic composition in the northwestern portion of the Paraná Basin, and can help our understanding of speciation pulses and dispersion patterns among the different Devonian basins in Gondwana.

KEYWORDS:

• Trilobitomorpha
• homalonotidae
• calmoniidae
• Pragian-Emsian
• paraná basin

Acknowledgements

The authors thank the Universidade Federal de Mato Grosso do Sul (UFMS), the Programa de Pós-Graduação em Biologia Animal, the Laboratório de Sistemática, Ecologia e Evolução at Instituto de Biociências (INBIO/UFMS), and the Laboratório de Zoologia (ZOO/UFMS). We are grateful to the Laboratório de Paleontologia at Universidade Federal de São Carlos, Campus Sorocaba, to the Instituto de Geociências da Universidade de São Paulo – IGC/USP and to the Universidade Estadual de São Paulo UNESP/BAURU for access to collections. We also thank the ceramic industries Campo Grande, Cotto Figueira and Fênix, as well as Alvanei Gomes, Expedito Viana, Marcelo Hansen and Ricardo, for their great help in accessing the outcrops. We thank Samuel Vilasbôas Pereira for the illustration and help in field activities, and Bruno Becker Kerber for his advice. We acknowledge the CNPq fellowship (process number 306216/2018-3).

Supplementary Material

CAP/1A-90; CGP/1A-4, CGP/1A-15, CGP/1A-18, CGP/1A-25, CGP/1A-29, CGP/1A-60, CGP/1A-64, CGP/1A-65, CGP/1A-66, CGP/1A-98, CGP/1A-200, CGP/1A-209, CGP/1A-211, CGP/1A-212, CGP/1A-217, CGP/1A-218.

Disclosure statement

No potential conflict of interest was reported by the author(s).