Subject: Didieraceae
From: [email-masked]
Date: 23 May 94 14:11:50 BST
Newsgroups: bionet.plants

The Didieraceae is a family of cactus mimics endemic to Madagascar.  They are
not true Cacti (members of the Cactaceae) all of which are endemic to the
Americas though many have been distributed around the globe and have been
naturalised in many countries.  Members of the Didieraceae are rarely found in
cultivation and I've never seen them naturalised outside their native
Madagascar.  They are extraordinary-looking plants, however, and might be very
decorative.  Given the huge problems that introduced Cacti have given to
Australia I would be hesitant to recommend widescale introduction of Didiera
into the Antipodes.

One proviso to my note on distribution of Cacti.  A single genus is believed to
be native outside the Americas and that is the genus Schlumbergera (previously
Zygocactus) which is widely cultivated in the UK as so-called "christmas
cactus".  Interestingly, it occurs in Madagascar!  My own view is that it is
unlikely to be truly native but might have been spread to Madagascar by birds. 
It grows as an epiphyte and has colourful, edible fruits.

P. Bacon
Dept Plant Science
Univ of Oxford