Abstract

Odontogriphus omalus was originally described as a problematic non-biomineralized lophophorate organism. Here we re-interpret Odontogriphus based on 189 new specimens including numerous exceptionally well preserved individuals from the Burgess Shale collections of the Royal Ontario Museum. This additional material provides compelling evidence that the feeding apparatus in Odontogriphus is a radula of molluscan architecture comprising two primary bipartite tooth rows attached to a radular membrane and showing replacement by posterior addition. Further characters supporting molluscan affinity include a broad foot bordered by numerous ctenidia located in a mantle groove and a stiffened cuticular dorsum. Odontogriphus has a radula similar to Wiwaxia corrugata but lacks a scleritome. We interpret these animals to be members of an early stem-group mollusc lineage that probably originated in the Neoproterozoic Ediacaran Period, providing support for the retention of a biomat-based grazing community from the late Precambrian Period until at least the Middle Cambrian.

1. Department of Natural History-Palaeobiology, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada
2. Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA
3. University of Bergen, Department of Biology, PO box 7800, N-5020 Bergen, Norway

Correspondence to: Jean-Bernard Caron¹ Correspondence and requests for materials should be addressed to J.-B.C. (Email: jcaron@rom.on.ca).

MORE ARTICLES LIKE THIS

These links to content published by NPG are automatically generated.