First report of the early Cambrian stem group brachiopod 'Mickwitzia' from East Gondwana

Abstract

The first mickwitziid brachiopod, 'Mickwitzia' sp., from East Gondwana is described from the lower Cambrian Ajax Limestone, Mt Scott Range in South Australia. The shells are fragmentary, but preserve sufficient details of morphology and micro-structure to allow positive identification to genus. The morphology of the dorsal valve apex and the extended cones on the internal surface indicate a close affinity with 'Mickwitzia muralensis' Walcott, 1913 from the early Cambrian of British Columbia, but scarcity of material precludes detailed comparison. This find extends the known range of the pivotal stem group brachiopod 'Mickwitzia' to East Gondwana.