Lochkovian (Early Devonian) brachiopods from the Garra Limestone at Eurimbla, New South Wales, Australia. Part 1: Acrotretida, Strophomenida, Productida, Orthotetida, Orthida and Pentamerida

The Garra Limestone at Eurimbla, is represented by a thick sequence of richly fossiliferous, occasionally silicified, sequence of carbonates and interbedded shales cropping out sporadically from underneath alluvial cover in Loombah Creek, central western N.S.W. Previous conodont work placing the Lochkovian (delta-pesavis zones)-Pragian (sulcatus Zone) boundary at 118 metres above the base of the section, is revised on the basis of supplementary sampling of previously unsampled, stratigraphically higher, carbonate horizons. All horizons with silicified brachiopods occur in the late Lochkovian pesavis Zone. The base of the Pragian is recognised at the first appearance of Eognathodus irregularis (DRUCE) at 793 metres above the base of the section. The definition and regional correlation of the pesavis Zone in Australia is discussed. The rhynchonelliformean brachiopods, collected from 15 silicified horizons, consist of over 8,000 individual shells or disarticulated valves classified into 48 genera, 8 subgenera, 54 species and 2 subspecies. The first part of this work documents 26 taxa (based on over 3,000 specimens) belonging to the Linguliformea: Lingulata (Acrotretida) and Rhynchonelliformea: Strophomenata (Strophomenida, Productida and Orthotetida) and Rhynchonellata (Orthida and Pentamerida). Two new species are described: Muriferella carolannae n. sp. and Sieberella murrayi n. sp. Locally, the fauna displays close similarities with the slightly younger (sulcatus Zone) faunas described from the Garra Limestone at Wellington. The broadly contemporaneous faunas to the south, at The Gap and Manildra show considerably less similarity.