Middle Devonian Crinoids from the Parnaiba Basin (Pimenteira Formation, Tocantins State, Brazil)

Abstract

This contribution presents the first description of crinoids from western margin of Parnaíba Basin. It also presents their first description in the Pimenteira Formation (Devonian of the Parnaíba Basin, state of Tocantins, Brazil). The material is represented by hundreds of columnals, pluricolumnals, as well as isolated calyx plates. Columnal and pluricolumnal morphology allowed the identification of Laudonomphalus aff. L. tuberosus, and Exaesiodiscus dimerocrinosus n. sp. Based upon calyx plate morphology a new Rhodocrinitidae species was erected, Monstrocrinus incognitus n. sp. The genera Exaesiodiscus, Laudonomphalus, and Monstrocrinus were previously described from the Devonian of Amazonas Basin. Exaesiodiscus dimerocrinosus is also identified from the northwest margin of Paraná Basin. The Monstrocrinus occurrence is rare in the Middle Devonian, until now known in Germany, Spain, and Algeria Lower Devonian (upper Emsian) and only in northern Brazil in the Middle Devonian (Eifelian.) These facts provide valuable arguments for paleogeographic interpretations regarding the pattern of distribution of invertebrates in this region of Gondwana and suggest potential migration routes in northern Gondwana during the Devonian.

A marine connection between Parnaíba and Paraná basins during the Eifelian/Givetian transition: review and new data

“…and a drift of western Gondwana towards the north, allowing the passage of these warm currents (Barret & Isaacson, 1988;Isaacson & Sablock, 1990;Isaacson & Díaz-Martínez, 1994;Isaacson, 1996Isaacson, , 2007Scheffler et al, 2011). The trilobite Metacryphaeus tuberculatus is known from Eifelian to lower Famennian in the Parnaíba Basin (Castro, 1968;Lieberman, 1993, Lieberman et al, 1991, and from uppermost Pragian to lower Frasnian in Bolivia (Lieberman, 1993) (2014), and in the Maecuru Formation (Eifelian) of the Amazonas Basin by Scheffler (2010) and Scheffler et al (2011).…”

“…The trilobite Metacryphaeus tuberculatus is known from Eifelian to lower Famennian in the Parnaíba Basin (Castro, 1968;Lieberman, 1993, Lieberman et al, 1991, and from uppermost Pragian to lower Frasnian in Bolivia (Lieberman, 1993) (2014), and in the Maecuru Formation (Eifelian) of the Amazonas Basin by Scheffler (2010) and Scheffler et al (2011). In addition, the occurrence of Salairocrinus?…”

Alguns Crinoides da Formação Ponta Grossa e suas afinidades paleobiogeográficas (Devoniano Inferior, Bacia do Paraná, Brasil)

“…), sendo que Lange (1943) chamou a atenção para a semelhança de fragmentos de pedúnculo do Paraná com os espécimens de Knod (1908). Os espécimens descritos e ilustrados por Katzer (1903Katzer ( , 1933 hoje são identificados como Laudonomphalus regularis (SCHEFFLER et al, 2006; para a Formação Maecuru) e Botryocrinus meloi (SCHEFFLER et al, 2013, no prelo; para a Formação Ererê), assim como é possível atribuir ao menos um espécimen de Knod (1908, pl. XXIX, fig.…”

Revisão sistemática e paleobiogeográfica de Trilobitas Phacopida (Homalonotidae e Calmoniidae) do Devoniano das Bacias do Parnaíba e Amazonas, Brasil

“…The new records of M. tuberculatus in the Emsian of Paraná Basin instigate a different palaeobiogeographic interpretation of that known for the brachiopods of the genus Tropidoleptus and the crinoid Exaesiodiscus Petri and Fulfaro, 1988;Scheffler, 2010;Scheffler et al, 2011). On the other hand, it is also possible that the arrival of M. tuberculatus in the Parnaíba Basin would have occured through a dispersive event that occurrs between Bolivia, Amazon Basin (Brazil), and Parnaíba Basin (Brazil).…”

“…Some organisms are indicators of these connections between the brazilian palaeozoic basins during the Devonian as brachiopods and crinoids of the genus Tropidoleptus and Exaesiodiscus 6 Scheffler, 2010;Scheffler et al, 2011). However, M. tuberculatus is a new species that confirm these connections.…”