Newly Described Protichnites eremita Ichnospecies

This Protichnites comes from the Krukowski Quarry, believed to be an outlier of the Mount Simon Sandstone. This quarry is currently under study as perhaps containing Ichnofossils of the earliest animals to venture ashore during the Middle Cambrian. Among the different trackway fossils found in this quarry (including Diplichnites and Climactichnites), Protichnites is the rarest both in terms of dispersion and absolute numbers. The sandstone slab here lacks ripples, suggesting that the tracks were made on a sand flat well above the tide, rather than underwater. This, in turn, suggests that the animal which made Protichnites tracks could have been one of the Earth's first air-breathing animals. The taxonomic identity of Protichnites makers from the Mount Elk Group is unknown. Aglaspids, crustaceans, chelicerates or members of a euryipterid stem group are among the arthropods that have been considered.

This particular specimen is the most recent Protichnites species first described in April 2009. Hagadorn and Seilacher hypothsize that the Protichnites eremita shown here was formed by so called hermite arthropods walked the Cambrian shore partially inside shells of other animals. This hermite crab-like strategy might have afforded the protection of a humid chamber that mitigated dessication of gills in the alien subaerial environment. The defining characteristic of Protichnites eremita is tail impressions that are angled to the left side of the track, as would be formed by a coiled shell intermittently scraping the sediment substrate. The presence of abundant sand stromatolites both above and below the tracks suggest that cyanobacterial mats mediated the preservation of Protichnites eremita.

To our knowledge, this is the only Protichnites eremita to be made commercially available. We've held it for three years pending the publication below.

Also visit the Cambrian Shadows Theme Park.

Reference: Hagadorn, J. W., and Seilacher, A., Hermits 500 million years ago?: Geology 37(4), 295-298 (2009).