I think that it might be M. karwinskiana ssp. nejapensis rather than M. karwinskiana ssp. beiselii, but not M. parkinsonii.
The spines appear to be all radial, one rather longer than the others, which is typical of M. nejapensis. M. beiselii has 1 central spine and 5-8 radials, often as long as the central. M. parkinsonii has 2-5 centrals and many, 30 or so, short radial spines.
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Chris43, moderator