Relaunching the TY tracksite: tridactyl dinosaur footprints from the Lower Jurassic of southern Africa

ABSTRACT Comprising more than 350 dinosaur footprints and at least 38 trackways, the TY tracksite described herein is located close to the border of NW Lesotho, near Teyateyaneng (TY), and is probably identical to the site originally mentioned by Dornan in 1908. The tridactyl footprints are exposed as natural casts on a cliff overhang and a fallen block at the base of the cliff in the uppermost Elliot Formation (Sinemurian, Lower Jurassic). High-resolution photogrammetry and zoom lenses facilitated the detailed ichnological documentation of the otherwise inaccessible overhang. The tracks vary greatly in morphology, likely due to moisture fluctuations in the tracking surface during their formation. Repeated wetting and drying of the track-bearing sediment is indicated by the cross-cutting relationship of the several generations of desiccation cracks and tracks. Two footprint size classes can be distinguished, with the smaller class being Grallator-like and the larger class being assignable to Eubrontes. All tracks are likely attributable to bipedal, small to moderately large theropod dinosaurs that roamed the drylands of the region c. 190 million years ago. Our ichnological account turns this aesthetic TY footprint site into an apt geoheritage destination with scientific and educational value for all.

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