Linguliformean brachiopods from the early Templetonian (Cambrian Series 3, Stage 5) Giles Creek Dolostone, Amadeus Basin, Northern Territory

Abstract

A small assemblage of linguliformean brachiopods (nine taxa) is documented from the Giles Creek Dolostone (Cambrian Series 3, Stage 5; Templetonian) in the Ross River Gorge area, NE Amadeus Basin, central Australia. Taxa described include: 'Aksarinaia subtilicrusta' Percival and Kruse 2014, 'Aphelotreta' cf. 'minuta' Rowell 1980, 'Eothele granulata' Roberts in Roberts and Jell 1990, 'Hadrotreta' sp., 'Micromitra nerranubawu' Kruse 1990, 'Prototreta millsi' Brock and Percival 2006, 'Westonia' cf. 'nyapungensis' Kruse 1990, as well as two species left under open nomenclature: Linguloidea gen. et sp. indet. and Acrotheloidea gen. et sp. indet. The Giles Creek Dolostone fauna has strong similarities to those described from the Koonenberry Belt (far western New South Wales), and the Gum Ridge Formation from the neighboring Georgina Basin (Northern Territory and Queensland). These comparable linguliformean brachiopod faunas are all considered to be of Ordian to early Templetonian age (Cambrian Series 2, Stage 4-Series 3, Stage 5), which agrees with the early Templetonian (Cambrian Series 3, Stage 5) age assessment for the Giles Creek Dolostone based on co-occurring trilobite fauna. The absence of typical Ordian brachiopods 'Schizopholis napuru' (='Karathele napuru') (Kruse 1990) and 'Kostjubella djagoran' (='Vandalotreta djagoran') (Kruse 1990) suggests that these taxa may have shorter ranges and, therefore, would be useful for stage subdivision.