PlantaeDB Logo
Login Sign-up

Genus Maireana in Family Amaranthaceae

In botanical taxonomy, a genus (plural genera) is a rank used to group closely related species within a family. In the hierarchy, genus sits below family and above species.

Genera are defined by shared morphological, anatomical, and genetic characteristics (for example, features of flowers, fruits, seeds, or leaves) that indicate a close evolutionary relationship among the species they contain.

Each genus can include one or more species. Examples include Rosa (roses) and Solanum (nightshades, including tomato and eggplant).

Do you wish to read more about plant taxonomy? Click here!

Genus Description

Suggest a correction!

Maireana (Moq.) is placed in the subfamily Camphorosmoideae of Amaranthaceae, a lineage that incorporates many former Chenopodiaceae genera (APG IV, 2016). The genus comprises approximately 100 species of low, often highly branched shrubs and subshrubs centered in Australia, with a broader occurrence across arid and semi-arid Australia and in coastal and inland saline habitats, and a minor presence in adjacent regions of Malesia (Wilson, 1975; Fuentes-Bazan et al., 2012). While lectotypification remains to be formally stabilized in standard references, the name has been consistently applied since its establishment by Moquin-Tandon (1840), and its circumscription is generally consistent with Maireana sensu Wilson (1975), distinct from related Australian genera such as Rhagodia and Chenopodium (POWO, 2024; WFO, 2024; GBIF, 2024).

Morphologically Maireana is recognized by a highly xeromorphic habit and a distinctive indumentum of mealy to scurfy, often grey–white, multicellular hairs on young growth; simple, alternate, usually fleshy to terete leaves lack stipules and commonly persist as reduced scales in some species. The inflorescences are axillary clusters of minute, wind‑pollinated flowers lacking perianth, the pistillate flower typically comprising a single scarious bract and a naked superior ovary with a single basal ovule; staminate flowers bear 1–5 stamens. Fruiting structures are key to identification: the perianth develops persistent membranous wings or lamellae, forming a papery “winged utricle” that promotes wind dispersal. Capsules are 1‑seeded and often persist on the plant, with exotestal ornamentation varying among species (Wilson, 1975; Fuentes-Bazan et al., 2012).

Species richness peaks in the temperate and subtropical arid interiors of Australia, with numerous endemics in the Southwest Australian Floristic Region and significant representation on coastal dunes and saltmarshes; most taxa occupy sandy or loamy substrates over a wide elevational range, from sea level to inland ranges. No broad phylogenetic analysis focused solely on Maireana has been published, but total‑evidence work on Camphorosmoideae has resolved Maireana as a monophyletic group distinct from Rhagodia and Chenopodium and allied to Australian genera such as Sclerolaena (Fuentes-Bazan et al., 2012). Within Maireana, sectional or subgeneric treatment is currently rare, and Wilson’s 1975 treatment is still the principal framework for species delimitation; synonymization of some taxa with Maireana oppositifolia remains contentious and not uniformly accepted (Wilson, 1975; Barker et al., 2008; Powell, 2008).

As a group, Maireana exhibits drought and salinity tolerance characteristic of Camphorosmoideae, and certain species are known for C4 photosynthesis and strong succulence; myrmecochory is locally frequent where fruits bear conspicuous wings that facilitate seed transport. The genus is economically significant: several species—including M. brevifolia—are widely planted for salt-tolerant amenity plantings, dune stabilization, and low‑input landscaping, while some taxa are valued forage during drought; few species are aggressive weeds, although M. prostrata can be locally invasive outside native ranges (Wilson, 1975; Barker et al., 2008).

Conservation assessments are uneven, with many species restricted to fragmented or degraded habitats, particularly in regions affected by grazing, salinity rise, and altered fire regimes; taxonomic uncertainty for several lineages complicates conservation planning. Continued field and systematic work across Australia's arid biome will refine species limits and conservation priorities for Maireana.

References: APG IV (2016); Barker et al. (2008); Fuentes-Bazan et al. (2012); GBIF (2024); Powell (2008); POWO (2024); WFO (2024); Wilson (1975).

Pick a Species to see its components: