New occurrences of Chonetoidea (Brachiopoda) in the Devonian of Bolivia, Peru and Antarctica

Abstract

Chonetoidea corresponds to one of the most abundant superfamilies throughout the Malvinokaffric Realm (Argentina, Uruguay, Bolivia, Paraguay, Antarctica, Peru and South-Central Brazil). In this paper we provided a better understanding of the diversity of this superfamily during the Devonian in southern Gondwana. For Bolivian specimens, we corroborate both the occurrence of Pleurochonetes anteloi in the Huamampampa Formation, that is, this species may have occurred at least in the Givetian, and the occurrence of Australostrophia mesembria in the Pragian-Emsian of Bolivia. We further identify both Aseptonetes isaacsoni in the Icla/Gamoneda Formation, which represents the oldest occurrence of this species, and Chonostrophia truyolsae in the Belén Formation/Bolivian Altiplano, thereby expanding its geographical distribution. We also provide the first description and illustration of a specimen of Chonetoidea from Antarctica and record the first occurrence of Australostrophia mesembria, Devonochonetinae indet. and Eodevonaria sp. in the Cabanillas Formation of Peru. Because A. mesembria is a typical Malvinokaffric species, this corroborates the extension of this realm into southern Peru.

KEYWORDS:
chonetoids; Malvinokaffric realm; Gondwana; systematic paleontology