Freshwater trionychid turtle plastron fragment Of hyoplastron (2)

I found this freshwater trionychid turtle plastron - fragment of hyoplastron? I belive it to be from Trionyx sp. from Bouldnor on the Isle of Wight .The geology of Bouldnor is Palaeogene (Oligocene epoch) this piece presented itself to me while scouring through some pebbles on the foreshore.

Beds : Hamstead Beds.

Formation: Bouldnor.

Member: Hamstead.

Group: Solent.

Stage: Rupelian.

Age: 34million years.

Epoch: Oligocene.