''Halophytum ameghinoi'' is a species of

herbaceous plant Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition o ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Patagonia Patagonia () is a geographical region that includes parts of Argentina and Chile at the southern end of South America. The region includes the southern section of the Andes mountain chain with lakes, fjords, temperate rainforests, and glaciers ...

. It is the only species in the genus ''Halophytum''. It is a

succulent In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

annual plant An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. Globally, 6% of all plant species and 15% of herbaceous plants (excluding trees and shrubs) are ...

, with simple, fleshy, alternate leaves. The plants are

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system comparable with gynomonoecy, andromonoecy and trimonoecy, and contras ...

, with solitary female

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s and

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s of male flowers on the same plant . ''Halophytum'' has sometimes been placed in its own

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

, Halophytaceae. For instance, the 2009

APG III system The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a f ...

and the 2003

APG II system The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly Molecular phylogenetics, molecular-based, list of systems of plant taxonomy, system of plant taxonomy that ...

recognise the family and assign it to the order

Caryophyllales Caryophyllales ( ) is a diverse and heterogeneous order of flowering plants with well-known members including cacti, carnations, beets, quinoa, spinach, amaranths, pigfaces and ice plants, oraches and saltbushes, goosefoots, sundews, Venu ...

in the clade

core eudicots The eudicots or eudicotyledons are flowering plants that have two seed leaves (cotyledons) upon germination. The term derives from ''dicotyledon'' (etymologically, ''eu'' = true; ''di'' = two; ''cotyledon'' = seed leaf). Historically, authors h ...

, although the 1998

APG system The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved ...

did not recognise such a family, placing its members in the family

Chenopodiaceae Amaranthaceae ( ) is a family of flowering plants commonly known as the amaranth family, in reference to its type (biology), type genus ''Amaranthus''. It includes the former goosefoot family Chenopodiaceae and contains about 165 genera and 2,040 ...

instead.

References

Caryophyllales Monotypic Caryophyllales genera Flora of Argentina Flora of Southern America Patagonia Taxa named by Carlo Luigi Spegazzini {{Caryophyllales-stub