Confused? Why the discrepancy?
Let us look at Baker's 'Bromeliaceae' (1889) where he placed Morren's var. plutonis and proserpinae as synonyms under Karatas acanthocrater. He pointed out that the reduced inner leaves were dark or light purple, rarely unchanged in colour (in other words often changing in colour!) and that plutonis and proserpinae only differed in the colour of the reduced inner leaves. Ever since 1889 both names have persisted in the horticultural World and accordingly confused from generation to generation!! See also Bromeliad Cultivar Registry 1998. Let us note here that Baker would have used 'Classical' colours where purple is described as "Dull Red"! (See W T Stearn's Botanical Latin page 249)
An answer might be found in Morren's paintings of Karatas acanthocrater held at Kew Gardens but so far I have been unable to arrange for anybody to view these records and advise. In any event, plants will still be distributed as 'Plutonis' whether with dark violet or dull red centres!
So I have changed tack and believe that the clone we call in Australia Neoregelia concentrica 'Red Centre' will have the name Neoregelia 'Ferris'.
I have dissected the inflorescence and measured the leaves and spines and cannot get past the description for Neoregelia concentrica except there does not appear to be blue tints in the reddish centre. I do not consider it to be a hybrid but a special form of the species.
A coloured photograph of this plant appeared on the front of the Proceedings of the Australian Bromeliad Conference held in Brisbane 1985."
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