An up-to-date familial and suprafamilial classification of succulent plants

Abstract

An up-to-date familial and suprafamilial classification of succulent plantsNyffeler , R; Eggli, U Nyffeler , R; Eggli, U (2010). An up-to-date familial and suprafamilial classification of succulent plants. Bradleya,

A synoptic review and new infrageneric classification for the genus Haworthiopsis (Xanthorrhoeaceae: Asphodeloideae)

“…Asphodeloideae [following APG III (Angiosperm Phylogeny Group 2009)] or alternatively in Asphodelaceae: Alooideae [following Nyffeler & Eggli (2010)]. In APG IV (Angiosperm Phylogeny Group 2016) the family circumscription is similar to that of APG III, but the family name is given as Asphodelaceae nom.…”

A revised generic classification for <i>Aloe</i> (Xanthorrhoeaceae subfam. Asphodeloideae)

“…Asphodeloideae [following APG III (APG 2009); alternatively Asphodelaceae, following Nyffeler & Eggli (2010)] comprise over 700 species in 15 genera, including the charismatic leaf succulent genus Aloe Linnaeus (1753: 319) and related alooid genera. A traditionally broad circumscription of Aloe and considerable infrageneric diversity (about 560 species) have been accommodated by traditional classifications at sectional, subsectional and series levels, or as informal infrageneric groups (Berger 1905, 1908, Reynolds 1950, 1966, Carter et al 2011.…”

Succulent plant diversity as natural capital

“…Succulence has evolved repeatedly in the plant kingdom, but estimates of this diversity vary. Estimates of the taxonomic extent of the condition range from 17 (Ogburn & Edwards, ) to 32 (Nyffeler & Eggli, ) of the 64 orders in the angiosperm tree of life (APG, ), as many as 83 plant families (Nyffeler & Eggli, ), and representing some 10,000 (Smith, ) to 12,500 (Nyffeler & Eggli, ) species. Succulent plants are common in environments in which water absorption is regularly limited by a water deficit caused by drought or freezing, salt accumulation and soil acidity, and in which plants are exposed to frequent physiological drought (Schimper, ).…”

“…Predominantly succulent plant families typically associated with these desert habitats include the hyperdiverse Euphorbiaceae (Horn et al, ) comprising more than 2,000 species, Aizoaceae (1,800 succulent species), Cactaceae (1,500 succulent species), and Apocynaceae (1,100 succulent species), and widespread but less speciose groups such as the aloes (Asphodelaceae, 500 succulent species) and the genus Agave (Agavaceae, 200 succulent species) (Arakaki et al, ; Bruyns, ; Gentry, ; Grace; International Cactaceae Systematics Group, ; Nyffeler & Eggli, ; Stevens, ). The extraordinary Orchidaceae, with 880 genera and some 26,000 species (Stevens, ), includes as many as 4,400 succulent species (Nyffeler & Eggli, ), many of which are found in arid and semi‐arid habitats. Globally, xeromorphic succulent diversity based on species numbers is geographically concentrated in five regions (Figure ), of which South Africa is by far the most diverse per unit area with over 4,600 taxa representing 350 genera and 58 families (Smith, ), including the Succulent Karoo: the only floristic region defined by its high proportion of succulent taxa (van Wyk & Smith, ).…”

“…Succulent plants are common in the world's drylands (Porse, ). Species numbers are shown for the five main global regions with xeromorphic succulent‐rich floras (black rectangles) (Eggli, ; Nyffeler & Eggli, ; van Wyk & Smith, ): (a) the Succulent Karoo of South Africa is by far the most species‐diverse and is the only biome defined by succulent plants; (b) these regions of high xeromorphic succulent diversity coincide alarmingly with global biodiversity hotspots (Myers et al, ), where the threat of extinction to unique biodiversity is high; (c) these regions are also places where people are most vulnerable to the socio‐economic risks of climate change, according to country‐specific forecasts of adaptive capacity (adapted from Yohe, ). Photographs: O.M.…”