The trilobite Maurotarion megacephalum n. sp (Aulacopleuridae) in the Lower Devonian from western Argentina: Phylogenetic and paleobiogeographic remarks

Abstract

Maurotarion megacephalum n. sp, from the Pragian (Lower Devonian) of the Talacasto Formation, Precordillera basin, central-west Argentina, is described and interpreted as the first Malvinokaffric species of the genus belonging not to the subgenus M. (Malvinotarion). Mainly based on librigenal characters, the coeval M. periergum, from Cortez Range, Nevada, USA, is considered the closest allied taxon. Evidences suggest faunal exchange between low and high paleolatitudes for the Pragian, a hypothesis previously discarded in light of low sea level conditions interpreted during this time, and linked to a pattern of vicariance and radiation previously recognized from endemic Malvinokaffric Maurotarion data.