only has ten fertile stamens without wings and lacks staminodes, except for G. pusillum that only has five stamens. Monsonia only has fifteen fertile stamens, which are merged at their base into a ring or merged at their base in trios with the middle filament longer than the others, except for M. brevirostrata with only five stamens. Erodium has five staminodes and five fertile stamens, without wings. Pelargonium has ten filaments without wings, between two and seven of which are topped by anthers, while the remaining three to eight are staminodes lacking anthers, but it can easily be distinguished by having only one narrow tube-like nectary inside what looks like the flowerstalk. Taxonomy Geraniaceae and Francoaceae are the two families included in the order Geraniales under the Angiosperm Phylogeny Group (APG) classification (APG IV). There has been some uncertainty in the number of genera to be included. Stevens gives seven genera listed here, while Christenhusz and Byng state five genera. Stevens also lists four synonyms of Geranium: Geraniopsis Chrtek Neurophyllodes (A. Gray) O. Degener Robertianum Picard Robertiella Hypseocharis, with between one and three species, which comes from the south-west Andean region of South America, is considered the sister to the rest of the family. Some authors separate Hyspeocharis as a monogeneric family Hypseocharitaceae, while older sources placed it in the Oxalidaceae. The genus Rhynchotheca has also been separated into the Vivianiaceae. The Geraniaceae have a number of genetic features unique amongst angiosperms, including highly rearranged plastid genomes differing in gene content, order and expansion of the inverted repeat. Phylogeny Recent comparison of DNA-fragments resulted in the following phylogenetic tree. Distribution and habitat Most species are found in temperate or warm temperate regions, though some are tropical. Pelargonium has its centre for diversity in the Cape region in South Africa, where there is a striking vegetative and floral variation. Gallery References Bibliography Sandro Pignatti, Flora d'Italia, Edagricole, Bologna 1982. Bakker, F.T., Culham, A., Hettiarachi, P., Touloumenidou, T., Gibby, M., 2004. Phylogeny of Pelargonium (Geraniaceae) based on DNA sequences from three genomes. Taxon 53, 17–28. External links Geraniaceae of Mongolia in FloraGREIF Rosid families