Phytolaccaceae

Phytolaccaceae

Synonymy

Phytolaccaceae R.Br., Narr. Exped. Zaire: 454. 1818, nom. cons., sec. APG III (2009)

Introduction

The family comprises herbs, trees or lianas distributed mainly in the Americas including the Antilles but with some members distributed in Australia and New Caledonia. They are characterised by styloids, elongate crystals, racemes or spikes and four-five tepals (Rohwer 1993a; Stevens 2001 onwards).
The circumscription of the family has long been controversial. Following the treatment by Rohwer (1993a) Phytolaccaceae have been disintegrated step by step according to the results of molecular phylogenetic studies (e.g. Cuénoud & al. 2002; Hilu & al. 2003; Schäferhoff & al. 2009; Brockington & al. 2011) which have shown that the subfamilies Agdestioideae, Barbeuioideae and Microteoideae (sec. Rohwer 1993a) are well-supported independent lineages. Therefore, these taxa are now treated at family level (see further notes under those families). These studies have also shown that Phytolaccaceae s.l. comprising the subfamilies Phytolaccoideae and Rivinoideae (sec. Rohwer 1993a) are not monophyletic. The most recent study by Brockington & al. (2011) included most of the genera recognized in these subfamilies and showed that the Phytolaccoideae (=Phytolaccaceae s.str.) represents a well-supported independent lineage, while the support for Rivinoideae is present but weak. Recent studies (J. Petersen, T. Borsch & P. Hernández-Ledesma, unpubl. data) show that the latter is probably more closely related to Nyctaginaceae than to Phytolaccaceae s.str. Rivinaceae have been recognised as an independent family within Caryophyllales by Stevens (2001 onwards). However, the correct family name for a clade that includes the genera Petiveria and Rivina would have to be Petiveriaceae C. Agardh (1824) and not Rivinaceae C. Agardh (1824). Both family names were published in the same work (Agardh 1824) but Meissner (1836) included Rivina under Petiveriaceae separate from Phytolaccaceae. This gives priority to Petiveriaceae. The taxon has a complicated taxonomic history. In some early treatments members were classified either within Phytolaccaceae and distinct from Petiveriaceae C. Agardh (Lindley 1853), or vice versa (e.g. Hutchinson 1959; Brown & Varadarajan 1985), or at an infrafamiliar or infrageneric level within Phytolaccaceae (e.g. Petiverieae, Rivinoideae, Rivineae) (including Petiveria and related genera) (e.g. Heimerl 1889, 1934; Rohwer 1993a).