Paleotethyan faunal/floral evidence in the Mississippian Maritimes Basin of Canada: An overview

Abstract

In this study, middle to late Mississippian microfossil assemblages from the Maritimes Basin of eastern Canada (Nova Scotia, SW Newfoundland, and New Brunswick) are closely compared to those from Western Paleotethys basins. The comparison is focused mainly on foraminifers and calcareous algae. Most foraminifers and algae described from the Maritimes Basin are considered cosmopolitan, and the occurrence in western Europe and northern Africa of taxa previously considered endemic to the North America Realm suggests a close paleobiogeographic relationship. This European/African correlation is further supported by other foraminiferal/algal taxa, the importance of which were previously overlooked, including: Plectogyranopsis ex gr. P. hirosei (Okimura, 1965), Mikhailovella Ganelina, 1956, Koktjubina windsorensis (Mamet, 1970), Polysphaerinella bulla Mamet, 1973, Mstinia Dain in Dain and Grozdilova, 1953, Haplophragmina Reitlinger, 1950, Omphalotis Shlykova, 1969, Pseudolituotuba Vdovenko, 1971, Pseudoendothyra Mikhailov, 1939, Saccamminopsis (Sollas, 1921) Vachard and Cózar, 2003, Kamaenella Mamet and Roux, 1974, and Anthracoporellopsis Maslov, 1956. Some species recorded in the Maritimes Basin have been typically recorded in Britain and Ireland in the southern platform of Laurussia. This implies a connection via the Rhenohercynian Ocean, whereas statistical analyses suggest that Maritimes Basin assemblages are closer to those of the Gondwana platform, which could have been established via the Paleotethys Ocean, and also with terranes northwest of the Variscan Front, in which its most logical connection should be with a still-open Rheic Ocean during the Visean and early Serpukhovian. Those taxa demonstrate a more-or-less continuous faunal and microfloral interchange between the Maritimes Basin and the Western Paleotethys paleobiogeographic realm. Furthermore, the width of the Paleotethys and Rheic oceans separating these regions is not considered excessive, particularly during the late Visean and early Serpukhovian.

Foraminifers and calcareous algae in Brigantian rocks as guides for the recognition of the Viséan-Serpukhovian boundary interval of Morocco

“…In consequence, apart for the abundance in stellate archaediscids, there are few similarities in the early Brigantian between the Meseta and the Sahara, with much more evolved foraminifers occurring earlier in the Sahara. This fact is probably related to a better marine connection with the Palaeotethys Ocean of the Saharan basins (such as Tindouf ) than with the Meseta, which shows stronger foraminiferal affinities with the southwest of the Iberian Peninsula (Sierra Morena) (Cózar et al 2018;Cózar & Somerville 2021c). Although markers for the recognition of the late Brigantian are roughly similar at the base in both regions, the diversity and numerical abundance are rather higher in the Sahara.…”