Rosa nanothamnus is only referred to as a synonym to Rosa giraldii in "Catalog of Life". http://www.catalogueoflife.org/col/details/species/id/a23ab7e47e9975a7793f4d13789145e5/synonym/c67a6e247499a0ed6825664bc6185c8e
Would not it be appropriate to combine the data on both taxa with HMF?
I would also suggest separating the sterile hybrid form from the Europa Rosarium Sangerhausen / Germany and recording it separately.
Rosa nanothamnus Boulenger has been listed as a subform of Rosa giraldii by Brumme & Gladis in the "Wildrosenverzeichnis" of the Rosarium Sangerhausen (p. 95). While we have listed this as a synonym, this publication gives no explanations on why this (and other) regrouping(s) was(were) made, which is a significant deficiency from a botanical viewpoint. It is quite possible that the Brumme & Gladis attributions will be questioned. Furthermore, there are other varieties of Rosa giraldii, the type being Rosa giraldii var. giraldiii. Therefore it is better to Keep Rosa nanothamnus and Rosa giraldii separate.
I see, the whole description is some what confusing, it says "White, near white or white blend Species" then further down says "pink". All the photographs show plants with strong pink coloured flowers.
The original description by Boulenger says "petals pink or white". The ARS colour classes are not always reliable, but are cited here. We have modified HMF's description to pink and white, too, thank you. Please also see the comment by Hortus, that the plant in Sangerhausen is actually a sterile hybrid. It is a general problem that wild roses in many Botanical Gardens are not the type, but some sort of seedlings. We cannot sort this out at HMF, but only show photos from different sites (and hope that some botanist will make a publication on the subject one day).
The plant shown here from the Europa-Rosarium Sangerhausen is a sterile hybrid, which was grown from seed more than 40 years ago by Bruno Müller, Palmengarten Frankfurt. The images from the Palmengarten show the mother plant of the hybrid plant the Europe Rosarium Sangerhausen.
