New Cambrian inarticulate Brachiopoda from Australasia and the age of the Tasman Formation

Abstract

Four new genera and species, Amictocracens teres, Picnotreta debilis, Stilpnotreta magna and Treptotreta jucunda are introduced for inarticulate brachiopods which occur in Middle and early Late Cambrian strata of the Georgina Basin, northeastern Australia and the Tasman Formation, northwestern Nelson, New Zealand. The brachiopod fauna of the Tasman Formation is fully described and shown to include a new species of Linnarssonia, L. tumida. Comparison of the Tasman Formation brachiopod assemblage with a faunal sequence established for the Georgina Basin shows it to be of early Boomerangian (Ptychagnostus cassis Zone) age and demonstrates the utility of Cambrian inarticulate brachiopods for interregional correlation.