A new species of the Devonian Lungfish Dipnorhyncus from Wee Jasper, New South Wales

Abstract

A new large mandible of Dipnorhynchus from the Early Devonian serotinus Zone (late Emsian) at Wee Jasper, is given the status of a new species, D. cathlesae n.sp. This fossil characterised by its size; relative depth with respect to its length; short anterior furrow, deeply bordered by a raised broad rim of dentary between itself and the labial pit; large foramen for a nerve in the posteromedial end of the labial furrow; a strong furrow from the adductor pit to the posterior end of the labial pit; thick dentary; lack of tubercles (blisters) on the prearticular plate; and an adductor pit wide posteriorly and narrowing gradually anteriorly. The surface of the tooth plate is not made of dentine, but of bone formed on the surface of the prearticular. This species represents the youngest known occurrence of Dipnorhynchus in the Murrumbidgee sequence.