Rosularia is a small genus of the family Crassulaceae. It includes about 28-35 species from Europe, the Himalayas, and northern Africa. Taxonomy Rosularia was originally described by De Candolle (1828) as a section of the genus Umbilicus, and raised to the level of genus by Stapf (1923) Thus the genus bears the botanical authority (DC) Stapf of both authors. In 1930 Berger included it in family Crassulaceae subfamily Sedoideae, as one of 9 genera. He further divided it into two sections (Eu-Rosularia and Ornithogalopsis) and further series, transferring some species of Sedum to it. Since then a number of species have been transferred in and out of the genus, including S. sempervivoides, which at one stage was placed in Prometheum. The genus Sempervivella was submerged in Rosularia. The genus is now placed within the Leucosedum clade, tribe Sedeae, subfamily Sempervivoideae of the Crassulaceae, but is embedded within Sedum paraphyletically. Species Rosularia contains about 28 species. The following species and subspecies were accepted by The Plant List (2013): Rosularia adenotricha (Wall. ex Edgew.) C.-A. Jansson Rosularia adenotricha subsp. viguieri (Raym.-Hamet) C.-A. Jansson Rosularia aizoon (Fenzl) A. Berger Rosularia alpestris (Kar. & Kir.) Boriss Rosularia alpestris subsp. marnieri(Raymond-Hamet ex H. Ohba) Eggli Rosularia blepharophylla Eggli Rosularia borissovae U.P.Pratov Rosularia chrysantha (Boiss. & Heldr. ex Boiss.) Takhtajan Rosularia cypria (Holmboe) Meikle Rosularia davisii Muirhead Rosularia elymaitica (Boiss. & Hausskn. ex Boiss.) A. Berger Rosularia glabra (Regel & Winkl.) A.Berger Rosularia globulariifolia (Fenzl) A. Berger Rosularia haussknechtii (Boiss. & Reut. ex Boiss.) A. Berger Rosularia jaccardiana (Maire & Wilczek) H. Ohba Rosularia libanotica (L.) Sam. Rosularia lineata (Boiss.) A.Berger Rosularia lutea Boriss. Rosularia pallida (Schott & Kotschy) Stapf Rosularia pallidiflora (Holmboe) Meikle Rosularia persica (Boiss.) A. Berger Rosularia pilosa (Fischer ex M. Bieberstein) Boriss. Rosularia platyphylla (Schrenk) A.Berger Rosularia radicosa (Boiss. & Hohen.) Eggli Rosularia rechingeri C.-A. Jansson Rosularia rosulata (Edgew.) H. Ohba Rosularia schischkinii Boriss. Rosularia sedoides (Decne.) H. Ohba Rosularia semiensis (J. Gay ex A. Richard) H. Ohba Rosularia sempervivoides (Fischer ex M. Bieberstein) Boriss. Rosularia serpentinica (Werderm.) Muirhead Rosularia serrata (L.) A.Berger Rosularia subspicata (Freyn) Boriss. Distribution and habitatRosularia is found in arid and semi-arid regions from N. Africa (Morocco, Ethiopia), through the eastern Mediterranean to Central Asia (north of Tien Shan and east of W Himalaya), including Pakistan. EcologyRosularia is an important larval host for the Central Asian butterfly Parnassius apollonius. Uses A number of species are cultivated as ornamental