Foot and shaft looks a creamy colour Rabutt. The centre tentacles do seem to swell like a BTA though.
It has taken a quarter of a raw King Prawn tonight, I believe it was just eating mysis and Brine Shrimp in the shop. Seffies favourite nem site says to give them a good feed when you get them as they will not have fed properley before. It is still a little folded from taking the prawn but is expanding once again.
The tentacles Rabutt are also translucent with similar markings on that you see on bubble corals and BTA's, I thought the tentacles on Malus were more opaque??