RAMIREZII   Carrillo, 2015

Published in Acta Botanica Mexicana  110, 2015 

Note :

Villadia ramirezii has a strange inflorescence, it looks like the combination of a spikate and a corymbose inflorescence. Spikate inflorescences are characteristic for genus Villadia, while corymbose inflorescences are characteristic for genus Sedum. The author compares Villadia ramirezii with Villadia platystyla. The latter however has a corymbose inflorescence and in the Crassulaceae volume of IHSP, 2003, is considered by 't Hart & Bleij to be a Sedum species. However it is true that S. platystylum is an atypical Sedum in so far as it has connate petals - the vast majority of Sedum species has free petals. On the other hand connate petals are characterisic for Villadia species - for this reason S. platystylum for some time in the past was considered a Villadia.

Diagnostic features for genus Sedum are corymbose inflorescences and free petals and for genus Villadia spikate inflorescences and connate petals.The two species in question however have corymbose inflorescences and connate petals, that means they do not fit well with either genus.

Corymbose inflorescences and connate petals are the diagnostic features of the recently abandoned genus Altamiranoa. Classifying the new species as Villadia and justifying this by re-classifying S. platystylum as Villadia is not very convincing. The resurrection of Altamiranoa would probably have been a better solution.

MB