Chenopodiaceae

Chenopodiaceae

Introduction

The family Chenopodiaceae is cosmopolitan predominantly occurring in temperate and subtropical regions, and especially in semi-arid or arid environments (Kühn 1993; Kadereit & al. 2003). Our delimitation of the Chenopodiaceae follows the concept of Ulbrich (1934), and Kühn (1993) with the exception of the Polycnemoideae (see Amaranthaceae). Considering that the core of Chenopodiaceae (composed of Betoideae, Chenopodioideae, Camphorosmoideae, Salicornioideae, Salsoloideae and Suaedoideae) is likely to be monophyletic, we maintain the Chenopodiaceae as a family distinct from the Amaranthaceae in line with a series of current taxonomic treatments and morphological, physiological and phylogenetic studies (Tzvelev (ed.) & al. 1996; Welsh & al. 2003; Zhu & al. 2003; Kadereit & al. 2005; Kapralov & al. 2006; Voznesenskaya & al. 2007; Akhani & al. 2007; Zacharias & Baldwin 2010; Kadereit & al. 2010; Sukhorukov 2010; Flores-Olvera & al. 2011; Sukhorukov & Kushunina 2014). We believe that name stability is important as it facilitates the assignment of genera to the respective major Amaranthaceae and Chenopodiaceae clades in line with the vast literature on Chenopodiaceae.
The monophyletic core Chenopodiaceae had already been found with maximum support based on matK-trnK sequence data (Müller & Borsch 2005a), although relationships of the six major subfamilies were not clear. Much progress has been made in the last decade on the internal relationships of Chenopodiaceae. Schütze & al. (2003) found two major clades of Suaedoideae Ulbr. to which Bienertia is sister. The Salicornioideae were clearly identified as monophyletic and are a lineage of about 90 species growing worldwide in coastal and inland saline habitats (Kadereit & al. 2006) with often succulent-articulated stems. Phylogenetic analysis yielded good support for the Camphorosmoideae that include several major lineages of mostly steppe, semi-desert and desert plants (Kadereit & Freitag 2011) but genera of the Salsoloideae such as Salsola L. were depicted as largely polyphyletic (Akhani & al. 2007; Kadereit & Freitag 2011). The Chenopodioideae were confirmed as monophyletic, although the members of the genus Chenopodium in its pre-phylogenetic circumscription appeared scattered across the subfamily, leading to a re-circumscription at genus and tribal level (Fuentes-Bazán & al. 2012a,b).

Synonymy

Chenopodiaceae Vent., Tabl. Regn. Veg. 2: 253. 1799, nom. cons., sec. Müller & Borsch (2005)