Notes on the typification of the name Rosa viscosa (Rosaceae) and clarification about the publication in which the name was firstly published

The name Rosa viscosa (Rosaceae), validly published by Gussone in his Supplementum ad Florae Siculae Prodromum, was recently lectotypified by Iamonico & Lattanzi on a specimen included in Jan’s collection and preserved at the Herbarium NAP. These authors provided an erroneous indication of the original reference of the name, citing Jan’s Catalogus Plantarum Phaenogamarum, ad Usum Botanophilorum Exsiccatarum (published in 1818) instead of Gussone’s Supplementum ad Florae Siculae Prodromus (published in 1832). Actually, the name R. viscosa does not appear in Jan’s Catalogus, while we traced it into a later published catalogue, i.e. Jan’s Elenchum Plantarum (published in 1831). However, R. viscosa is there invalid being a nomen nudum. So, since the name reported in the taxonomic treatment by Iamonico & Lattanzi is linked to a reference (Jan’s Catalogus Plantarum Phaenogamarum) where that name does not occur, the typification would not be applicable, and a revision is here proposed. It should be noted that a clear indication in the Madrid Code as to how to handle a situation like this does not appear. Furthermore, we noted that Jan’s catalogue is reported as original reference of R. viscosa by all the major databases of plant names and other sources, whereas Jan’ Elenchus is never cited.