''Donatia'' is a genus of two

cushion plant A cushion plant is a compact, low-growing, mat-forming plant that is found in alpine, subalpine, arctic, or subarctic environments around the world. The term "cushion" is usually applied to woody plants that grow as spreading mats, are limited in ...

species in the family

Stylidiaceae The family Stylidiaceae is a taxon of dicotyledonous flowering plants. It consists of five genera with over 240 species, most of which are endemic to Australia and New Zealand. Members of Stylidiaceae are typically grass-like herbs or small shrub ...

. The name commemorates

Vitaliano Donati Vitaliano Donati (8 September 1717 – 26 February 1762), born in Padua in Italy, was an Italian doctor, archeologist, and botanist. He took the degree of Doctor of Philosophy in 1739. He was interested in the flora and fauna of the Adriatic, and ...

, an Italian botanist. ''Donatia'' has been placed in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Donatioideae, described by

Johannes Mildbraed Gottfried Wilhelm Johannes Mildbraed (19 December 1879 – 24 December 1954) was a German botanist that specialized in mosses, ferns, and various spermatophytes. He is well known for authoring the most current monograph and taxonomic treatment of ...

in his 1908 taxonomic monograph of the family

. The subfamily was created to distinguish the difference between the single

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Donatia'' from the five typical

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

of the Stylidiaceae that Mildbraed placed in the Stylidioideae subfamily.Mildbraed, J. (1908). Stylidiaceae. ''In'' Engler, A. ''Das Pflanzenreich: Regni vegetabilis conspectus'', IV. 278. Leipzig, 1908. The subfamily taxonomy represented the taxonomic uncertainty of ''Donatia'', which had at one point also been placed in the

Saxifragaceae Saxifragaceae is a family of herbaceous perennial flowering plants, within the core eudicot order Saxifragales. The taxonomy of the family has been greatly revised and the scope much reduced in the era of molecular phylogenetic analysis. The f ...

.Wagstaff, S.J. and Wege, J. (2002)
Patterns of diversification in New Zealand Stylidiaceae
. ''American Journal of Botany'', 89(5): 865-874.Good, R. (1925). On the geographical distribution of the Stylidiaceae. ''New Phytologist'', 24(4): 225-240. ''Donatia'' differs sufficiently from the genera in the Stylidiaceae in that it has free

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s and petals, paracytic

stomata In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bor ...

, and a pollen morphology distinct from the other genera. Because of this and the recent

phylogenetic analysis In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

based on ''rbcL'' genes, more recent treatments have segregated ''Donatia'' into its own family, the Donatiaceae. The molecular phylogenetic analysis has placed ''Donatia'' as a sister-group to Stylidiaceae, thus leaving the Stylidiaceae as a

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

family.Laurent, N., Bremer, B., and Bremer, K. (1999). Phylogeny and generic interrelationships of the Stylidiaceae (Asterales), with a possible extreme case of floral paedomorphosis. ''Systematic Botany'', 23(3): 289-304.Lundberg, J. and Bremer, K. (2003). A phylogenetic study of the order Asterales using one morphological and three molecular data sets. ''International Journal of Plant Sciences'', 164: 553-578. Donatia fascicularis from Endeavour voyage

Donatia fascicularis from Endeavour voyage

As early as three years after Mildbraed's publication of the subfamily Donatioideae, other authors began to question the placement and argued for recognition of Donatiaceae. In 1915,

Carl Skottsberg Carl Johan Fredrik Skottsberg (1 December 1880 – 14 June 1963) was a Swedish botanist and explorer of Antarctica. Life Skottsberg was born in Karlshamn on 1 December 1880 the son of Carl Adolf Skottsberg a schoolmaster and his wife, Maria L ...

formally published the Donatiaceae.Skottsberg, C. (1915). Notes on the relations between the floras of subantarctic America and New Zealand. ''Plant World'', 18: 129-142. The

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-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gro ...

recommended the inclusion of ''Donatia'' in Stylidiaceae but allowed for the optional recognition of the family Donatiaceae. The

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 fur ...

merges Donatiaceae into Stylidiaceae. The two species in the genus represent a wide geographic range. ''D. novae-zelandiae'' is found in the

alpine Alpine may refer to any mountainous region. It may also refer to: Places Europe * Alps, a European mountain range ** Alpine states, which overlap with the European range Australia * Alpine, New South Wales, a Northern Village * Alpine National Pa ...

and

subalpine Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...

regions of

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

and

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

while ''D. fascicularis'' is native to similar habitats in southern

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

to latitude 40°S. In Chile ''

Donatia fascicularis ''Donatia fascicularis'' is a species of cushion plant in the family Donatiaceae and is closely related to species in the family Stylidiaceae. It is found in the alpine and subalpine regions of western Patagonia and Tierra del Fuego. It is the ...

'' is, together with '' Astelia pumila'', dominant in the

cushion A cushion is a soft bag of some ornamental material, usually stuffed with wool, hair, feathers, polyester staple fiber, non-woven material, cotton, or even paper torn into fragments. It may be used for sitting or kneeling upon, or to soften th ...

bogs that exists in areas exposed to the Pacific coast. As such it is not usually found together with ''

Sphagnum ''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, peat moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store wa ...

'' which tend to grow slightly more inland.

References

Stylidiaceae Asterales genera {{Stylidiaceae-stub