Huerteales is the botanical name for an order of flowering plants.[2] It is one of the 17 orders that make up the large eudicot group known as the rosids in the APG III system of plant classification.[1][3] Within the rosids, it is one of the orders in Malvidae,[4] a group formerly known as eurosids II and now known informally as the malvids. This is true whether Malvidae is circumscribed broadly to include eight orders as in APG III, or more narrowly to include only four orders.[1] Huerteales consists of four small families, Petenaeaceae, Gerrardinaceae, Tapisciaceae, and Dipentodontaceae.[5]
Petenaeaceae consists of a single genus and species Petenaea cordata from Southern Mexico, Guatemala and Belize.[6]
Gerrardinaceae consists of a single genus, Gerrardina.[7] Tapisciaceae has two genera, Tapiscia and Huertea.[8][9]
Until 2006, Dipentodontaceae was treated as consisting of a single genus, Dipentodon.[10] Since that time, some authors have included Perrottetia in Dipentodontaceae, even though no formal revision of the family has been published as of 2008.[11] Thus the order Huerteales consists of six genera. The largest genus, Perrottetia, contains about 15 of the approximate total of 25 species in the order.[12]
The Huerteales are shrubs or small trees found in most tropical or warm temperate regions. The flowers of Perrottetia have been studied in detail,[13] but otherwise, all five of the genera are poorly known. The order is based on molecular phylogenetic analysis of DNA sequences.
All of the Huerteales are woody plants. The leaves are alternate with toothed margins. The inflorescence is cymose, but sometimes nearly racemose or umbelliform. The bases of the calyx, corolla and stamens are fused to form a hypanthium which is in some cases very short. The ovary is unilocular, at least at the top, with one or two ovules per carpel. The number of carpels is variable.