Phylogeny, biogeography and ecological diversification of Sarcocornia (Salicornioideae, Amaranthaceae)

Abstract

Sarcocornia diversified in salt-laden environments worldwide, repeatedly evolving superficially similar prostrate, mat-forming habits that seem advantageous in stressed environments with prolonged flooding, high tidal movement and frost. Some of these prostrate-habit types might be considered as ecotypes (e.g. S. pacifica or S. pillansii) while others represent good ecospecies (e.g. S. perennis, S. decumbens, S. capensis), hence representing different stages of speciation.

A new species ofArthrocnemum(Salicornioideae: Chenopodiaceae-Amaranthaceae) from West Africa, with a revised characterization of the genus

“…Indeed, many morphological or even anatomical characters of both articulated Arthrocnemum splits longitudinally into two parts in the fruiting stage (essentially making the fruit free), as well as having a thinner pericarp and brown (not black as in Eurasian Arthrocnemum) seeds with no papilla-like outgrowths. Steffen et al (2015) suggest that A. subterminale is not related to Arthrocnemum s.str. Another species, Arthrocnemum indicum, which is widely distributed in the coastal zones of the Indian Ocean (East and Southern Africa, Sub-Indian continent and Australia), has been transferred to Halosarcia Wilson (Wilson 1980) and then to Tecticornia Hook.f., a genus with the highest diversity in Australia (Shepherd, Waycott and Calladine 2004;Shepherd 2007;Shepherd and Wilson 2007).…”

“…10.1]), and none of the species recognized by MoquinTandon (1840) is appropriate for the typification. This and Salicornia including paraphyletic Sarcocornia (Shepherd, Macfarlane and Waycott 2005b;Steffen et al 2015) are overlapping (Zare and Keshavarzi 2007). Despite many morphological homologies (shrubby life history; glabrous stem; opposite scale-like leaves and bracts; cymes consisting of three flowers; rupture of the lower part of both perianth and pericarp making the ripe seed free; vertical embryo position) and similar (saline) habitats, there are several important traits unambiguously distinguishing Arthrocnemum from the Salicornia/Sarcocornia group (Table 1; see also De Fraine 1913;Ferguson 1964;Sukhorukov 2014).…”

Biodiversity hotspots and Ocbil theory

“…10). Whether ancient salt lake systems occur in other Ocbils remains poorly known, but the GCFR has possible candidates (Steffen et al 2015). Recent and rapid spread of some groups such as Salicornia in these GCFR systems is evident (Slenzka et al 2013).…”

The name "Salicornietum perennis" ("sensu lato") and global nomenclatural issues

“…The taxonomical status of Salicornia/Sarcocornia has been discussed in recent years, with proposals of segregation into two independent genera or its assimilation. Molecular and taxonomical studies have supported their independence 2007;Steffen et al, 2010;Guilló, 2013), but the more recent studies with many sampled species and wide distribution have supported their assimilation, because Salicornia is nested within Sarcocornia, which means that Sarcocornia is a paraphyletic taxon (Steffen et al, 2015;Piraiinen et al, 2017). In this paper, we adopted the current decision of considering a single genus Salicornia, supported by those recent studies.…”