The diverse radiodont fauna from the Marjum Formation of Utah, USA (Cambrian: Drumian).

Radiodonts have long been known from Cambrian deposits preserving non-biomineralizing organisms. In Utah, the presence of these panarthropods in the Spence and Wheeler (House Range and Drum Mountains) biotas is now well-documented. Conversely, radiodont occurrences in the Marjum Formation have remained scarce.

Controls on gut phosphatisation: the trilobites from the Weeks Formation Lagerstätte (Cambrian; Utah).

Despite being internal organs, digestive structures are frequently preserved in Cambrian Lagerstätten. However, the reasons for their fossilisation and their biological implications remain to be thoroughly explored. This is particularly true with arthropods--typically the most diverse fossilised organisms in Cambrian ecosystems--where digestive structures represent an as-yet underexploited alternative to appendage morphology for inferences on their biology.