During the four years that have elapsed since he spoke at our July 2004 Show, Wolfgang has made more field studies in north-west Mexico, and his talk  looked at this area and covered his evolving ideas about the evolution and classification of the straight-spined Mammillaria species from this area.

Wolfgang illustrated his talk with many photographs of plants from habittat in Chiuhuahua, Sonoroa, Sinaloa and Durango. A main theme in his talk was the possibility that the development of the species found in this region of NorthWest Mexico has followed the river valleys, and that this can be seen from the location of the species. As a result the current classifications and groupings may need to be reviewed and re-aligned.

Of especial interest were the photographs of Mammillaria temorisensis, of the real lindsayi, the "lindsayi impostor" Mammillaria sinforosensis, as well as some as yet unpublished new plants.

A fuller report will be in the Journal later this year.