Hi Eric- Arum italicum 'Pictum' seems to be synonymous with Arum italicum 'Marmoratum' in that I don't think there are any named varieties to distinguish one from the other.

Over the years, mail order nurseries have tried to sell under the name 'Pictum' for as much as $35.00 for a dormant tuber, but this won't guarantee that you will get anything better than tubers sold as 'Marmoratum' which are variable in color and variegation. Dutch bulb importers like McClure & Zimmerman sell these very inexpensively although the actual foliage will be quite variable from year to year.

I think culture in Southern CA should be about the same as it it is in South Texas- They only grow during the winter here, flowering, setting berries and going dormant by Easter.

Main point to insure a successful planting in South Texas is to only take delivery in autumn rather than spring as they are ready to go dormant in spring and will probably never recover.

Best wishes