Pleistocene golden mole and sand-swimming trace fossils from the Cape coast of South Africa

Michael R Perrin,Hayley C Cawthra,Jan C De Vynck,Charles W Helm,Martin G Lockley

doi:10.1017/qua.2020.97

Michael R Perrin, Hayley C Cawthra + Show 3 more

https://doi.org/10.1017/qua.2020.97

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Abstract

AbstractMore than 250 Pleistocene vertebrate trace fossil sites have been identified on the Cape south coast of South Africa in aeolianites and cemented foreshore deposits. These discoveries, representing the epifaunal tracks of animals that moved over these sand substrates, complement traditional body fossil studies, and contribute to palaeo-environmental reconstruction. Not described in detail until now, but also important faunal components, are the infaunal traces of animals that moved within these sandy substrates. Six golden mole burrow trace sites (Family Chrysochloridae) have been identified on the Cape south coast. In addition, three sites, including one on the Cape southeast coast, have been identified that show evidence of sand-swimming, probably by a golden mole with a means of locomotion similar to that of the extantEremitalpagenus. Such traces have not been described in detail in the global ichnology record, and merit the erection of a new ichnogenusNatatorichnus, with two ichnospecies,N. subarenosaichnosp. nov andN. sulcatusichnosp. nov. Care is required in the identification of such traces, and the orientation of the trace fossil surface needs to be determined, to avoid confusion with hatchling turtle tracks. Substantial regional Pleistocene dune environments are inferred from these sand-swimming traces.

Highlights

Since its inception in 2008, the Cape south coast ichnology project has yielded a growing data set of Pleistocene vertebrate tracksites from the South African coast between the town of Arniston in the west and the Robberg peninsula in the east (Helm et al, 2020a) (Fig. 1)
Some of the sand-swimming features we describe are ichnologically intermediate between epifaunal trackways and the deeper infaunal burrows made by other members of the golden mole family
Description follows of three other sites (Sites A, B and C), from west to east, that suggest sand-swimming golden moles as tracemakers

Summary

Introduction

Since its inception in 2008, the Cape south coast ichnology project has yielded a growing data set of Pleistocene vertebrate tracksites from the South African coast between the town of Arniston in the west and the Robberg peninsula in the east (Helm et al, 2020a) (Fig. 1). More than 250 such sites have been identified in aeolianite and cemented foreshore deposits, indicating a diverse trace fossil record with the potential to complement and greatly enhance the rich traditional body fossil archive in the region (e.g., Klein, 1976, 1983; Klein et al, 2007; Rector and Reed, 2010; Marean et al, 2014; Matthews et al, 2019), which is derived largely from archaeological sites and scavenger dens Examples of these ichnological findings include reports of hatchling turtle. The search for vertebrate trace fossil sites was extended to the Cape southeast coast to Algoa Bay, east of Port Elizabeth, with the identification of further ichnofossil sites (Fig. 1)

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