Mammillaria pottsii

{{Short description|Species of cactus}}

{{Speciesbox

|image = DBG Mammillaria Pottsii.jpg

|genus = Mammillaria

|species = pottsii

|authority = Scheer ex Salm-Dyck

|synonyms = Cactus pottsii

Chilita pottsii

Leptocladia leona

Mammillaria leona

Neomammillaria pottsii

}}

Mammillaria pottsii, also known as fox-tail cactus or rat-tail nipple cactus, is a species of flowering plant in the family Cactaceae.{{cite web|title=Mammillaria pottsii|url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242415363|work=Flora of North America|accessdate=28 January 2011}} It was first described by Scheer ex Salm-Dyck, Cact. Hort. 1849: 104 (1850){{cite web|title=Mammillaria pottsii|url=http://www.mammillarias.net/gallery/mammillaria_species.php?searchstring=pottsii&lg=uk|accessdate=28 January 2011|archive-url=https://web.archive.org/web/20101124202429/http://mammillarias.net/gallery/mammillaria_species.php?searchstring=pottsii&lg=uk|archive-date=24 November 2010|url-status=usurped}} According to the United Nations Environment Programme, M. leona is a synonym for M. pottsii.{{cite web|title=Mammilaria pottsii|url=http://sea.unep-wcmc.org/isdb/CITES/Taxonomy/tax-species-result.cfm?displaylanguage=eng&source=plants&Genus=Mammillaria&Species=pottsii&Country=&tabname=names|publisher=United Nations Environment Programme, World Conservation Monitoring Centre|accessdate=29 January 2011}}{{Dead link|date=March 2020 |bot=InternetArchiveBot |fix-attempted=yes }}