The

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Stylidiaceae is a taxon of

dicot The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, t ...

yledonous

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. They include all forbs (flowering plants without a woody stem), grasses and grass-like plants, a vast majority of ...

s. It consists of five genera with over 240 species, most of which are

endemic Endemism is the state of a species being found 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 found els ...

to Australia and

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 List of islands of New Zealand, smaller islands. It is the ...

. Members of Stylidiaceae are typically grass-like herbs or small shrubs and can be perennials or annuals. Most species are free standing or self-supporting, though a few can be climbing or scrambling ('' Stylidium scandens'' uses leaf tips recurved into hooks to climb). The pollination mechanisms of ''

Stylidium ''Stylidium'' (also known as triggerplants or trigger plants) is a genus of dicotyledonous plants that belong to the family Stylidiaceae. The genus name ''Stylidium'' is derived from the Greek ''στύλος'' or ''stylos'' (column or pillar), wh ...

'' and '' Levenhookia'' are as follows: In ''Stylidium'' the floral column, which consists of the fused

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 filam ...

and style, springs violently from one side (usually under the flower) when triggered. This deposits the pollen on a visiting insect. In ''Levenhookia'', however, the column is immobile, but the hooded labellum is triggered and sheds pollen. In 1981, only about 155 species were known in the family. The current number of species by genus (reported in 2002) is as follows: ''Forstera'' - 5, ''Levenhookia'' - 10, ''Oreostylidium'' - 1, ''Phyllachne'' - 4, and ''Stylidium'' - 221. These numbers, especially for ''Stylidium'', are changing rapidly as new species are described.Wagstaff, S.J. and Wege, J. (2002). Patterns of diversification in New Zealand Stylidiaceae. ''

American Journal of Botany The ''American Journal of Botany'' is a monthly peer-reviewed scientific journal which covers all aspects of plant biology. It has been published by the Botanical Society of America since 1914. The journal has an impact factor of 3.038, as of 201 ...

'', 89(5): 865-874. (Available online
HTML
o
PDF
versions). ''Stylidium rotundifolium'' appeared in Joseph Banks' Florilegium (plate 173), drawn from a specimen collected at Endeavour River, Australia in 1770.

Taxonomy

The genus '' Donatia'' is sometimes included in Stylidiaceae in the monogeneric subfamily Donatioideae. 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 Gr ...

recommends its inclusion in Stylidiaceae but allows for the optional recognition of the family Donatiaceae.Stylidiaceae
(at th
Angiosperm Phylogeny Website
Molecular and phylogenetic analysis have determined that ''Donatia'' is a sister-group to Stylidiaceae and therefore placing ''Donatia'' in its own family has been recommended by several authorities. Including ''Donatia'' within the Stylidiaceae would endanger its status 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 ...

group. Donatioideae and Stylidioideae were 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 subfamilies were created to distinguish the difference between 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 ...

of the Stylidiaceae from the single genus '' Donatia'', which Mildbraed placed in Donatioideae.Mildbraed, J. (1908). Stylidiaceae. ''In'' Engler, A. ''Das Pflanzenreich: Regni vegetabilis conspectus'', IV. 278. Leipzig, 1908. The subfamily taxonomy represents the taxonomic uncertainty of ''Donatia'', which has often been placed in its own family, Donatiaceae, or other families such as 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 ...

.Good, R. (1925). On the geographical distribution of the Stylidiaceae. ''New Phytologist'', 24(4): 225-240. Mildbraed's classification also included two

tribes The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confl ...

: Phyllachneae, which included the genera ''Forstera'' and ''Phyllachne'', and Stylidieae, which included ''Levenhookia'', ''Oreostylidium'', and ''Stylidium''. This level of infraspecific taxonomy is not used in recent research, but the groupings are supported by molecular data that suggest ''Forstera'' and ''Phyllachne'' are closely related but distinct from the other three. APG II places Stylidiaceae and Donatiaceae in the

Asterales Asterales () is an order of dicotyledonous flowering plants that includes the large family Asteraceae (or Compositae) known for composite flowers made of florets, and ten families related to the Asteraceae. While asterids in general are chara ...

. The

Cronquist system The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in a series of monographs and texts, including ''The Evolution and Classification of Flowering Plants'' (1968; 2nd edition, 1988) ...

placed both families in the Campanulales. The Takhtajan and Reveal systems place both families in the order Stylidiales. The

Dahlgren system One of the modern systems of plant taxonomy, the Dahlgren system was published by monocot specialist Rolf Dahlgren in 1975 and revised in 1977, and 1980. However, he is best known for his two treatises on monocotyledons in 1982 and revised in 1 ...

uses the same Stylidiales order, but it omits Donatiaceae. The Thorne system shifts Stylidiaceae into the

Saxifragales The Saxifragales (saxifrages) are an order of flowering plants (Angiosperms). They are an extremely diverse group of plants which include trees, shrubs, perennial herbs, succulent and aquatic plants. The degree of diversity in terms of vege ...

order.

References

External links

Stylidiaceae Family Description
{{Taxonbar, from=Q132216 Flora of Australasia Asterales families