Early Idamean (Late Cambrian) agnostoid trilobites from the Huskisson River, Tasmania

Abstract

Two trilobite taxa, Agnostus (Homagnostus) sp. and Pseudagnostus (Pseudagnostus) idalis huskissonensissubsp. nov. are described from the upper part of the Huskisson Group, western Tasmania. The only trilobite previously described from this level is the early Idamean (early Late Cambrian) zone fossil Glyptagnostus reticulatus. Palaeontological and stratigraphic evidence suggests that there may be a disconformity of very late Middle Cambrian age (about Lejopyge laevigata III Zone) within the Huskisson Group, which would correspond to a postulated disconformity of similar age from the Dundas Group at Dundas.