Peter Boyce on Arum italicum and A. concinnatum
Graham Rice (Mon, 16 Apr 2007 13:49:31 PDT)

I emailed Peter Boyce on the issue of Arum synonymy we were
discussing last week.

Here's what he says:

This issue of synonymy is linked to the true application of the name
Arum italicum subvar. (not var.) marmoratum (Schott) Engl. Pflanzenr.
IV.23F: 85 (1920) [basionym Arum marmoratum Schott, Prod. Syst.
Aroid: 86 (1860)] and is nothing to do with with the heterotypic
cultivar (culton) 'Marmoratum' Hort.

Schott's type of his name marmoratum (an excellent life-size painting
with fully diagnostic characters) is unquestionably conspecific with
A. concinnatum.

All clear?!

I think what it all boils down to is this: Schott first published the
name Arum marmoratum in 1860. Later, in 1920, Engler reduced it in
rank to Arum italicum subvar. marmoratum. However, back in 1860
Schott had illustrated it with a perfect painting of Arum
concinnatum! So the original publication of the name Arum marmoratum
was invalid.

The cultivar name 'Marmoratum' was used much later and, as has been
remarked, might well be better as a group name.

I think that's it... rushing to pack to leave for two weeks in
England. And, as it's snowing here in PA!, I want to pop out and see
if the skunk cabbage is doing its thing and melting the snow.

Graham Rice
http://transatlanticplantsman.com/

BTW The new edition of the RHS PlantFinder is now online, I've
written it up here:
http://transatlanticplantsman.typepad.com/transatl…