This cast came from just west of chilton chine on the Isle of Wight. Wealden early Cretaceous.
the sandstone it comes from is found all over the beach in blocks and is riddled with foot casts of mainly iguanodons. Sauropods, crocodiles and theropods also known in this location.
I have not seen anything similar to this in the area, and given the heavy dinoturbation of this particular sandstone layer I think there is a good chance this is part of a dinosaur or croc tail drag cast.
I can’t see how it can be made by anything plant based or geological, but would be very interested in anyones opinion for or against my interpretation.
I’ve packed it away now, but it’s roughly 10cm wide.