I would think tenuis as well, but the coralites don't look defined enough to be a tenuis. looks to me like it might be a kimbeensis like this one just with less polyp extension Drs. Foster and Smith Diver's Den® - Acropora kimbeensis
That looks to be it andy woukd make sense in a way as most of the coral collected for the stores around me is from around australia its got less polyp extention just not much as I only jist added it to the tank