''Isotoma'' is a

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 ...

of annual and perennial

herbs In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

in the

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

Campanulaceae The family Campanulaceae (also bellflower family), of the order Asterales, contains nearly 2400 species in 84 genera of herbaceous plants, shrubs, and rarely small trees, often with milky sap. Among them are several familiar garden plants belon ...

and are native to Australia and New Zealand.

Description

Plants in the genus ''Isotoma'' have milky sap, a distinct taproot and sometimes

adventitious roots Important structures in plant development are buds, shoots, roots, leaves, and flowers; plants produce these tissues and structures throughout their life from meristems located at the tips of organs, or between mature tissues. Thus, a living plant ...

along the branches. The leaves are arranged alternately and are usually toothed or lobed. The flowers are solitary in leaf

axil A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...

s or arranged in groups on the ends of branchlets. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

s form a short tube with lobes. The

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

tube is slightly

zygomorphic Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts. Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirall ...

with five lobes spreading horizontally, the upper two smaller and the lower three often with distinct markings. The

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 are fused to the petal tube. The fruit is an urn-shaped or conical capsule containing a large number of minute seeds.

Taxonomy and naming

In 1810, in his book ''

Prodromus Florae Novae Hollandiae et Insulae Van Diemen ''Prodromus Florae Novae Hollandiae et Insulae Van Diemen'' (Prodromus of the Flora of New Holland and Van Diemen's Land) is a flora of Australia written by botanist Robert Brown and published in 1810. Often referred to as ''Prodromus Flora Novae ...

'', Robert Brown described ''Lobelia hypocrateriformis'' and placed it in

section Section, Sectioning or Sectioned may refer to: Arts, entertainment and media * Section (music), a complete, but not independent, musical idea * Section (typography), a subdivision, especially of a chapter, in books and documents ** Section sign ...

''Isotoma''. Then in 1826, based on Brown's description,

John Lindley John Lindley FRS (5 February 1799 – 1 November 1865) was an English botanist, gardener and orchidologist. Early years Born in Catton, near Norwich, England, John Lindley was one of four children of George and Mary Lindley. George Lindley w ...

raised the genus ''Isotoma'' in ''

The Botanical Register ''The Botanical Register'', subsequently known as ''Edwards's Botanical Register'', was an illustrated horticultural magazine that ran from 1815 to 1847. It was started by the botanical illustrator Sydenham Edwards, who had previously illustrate ...

''. The name ''Isotoma'' is derived from

ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

words meaning "equal" and "a piece cut off" or "a slice". The name was originally applied to the section ''Isotoma'' because those species differ from true lobelias in having petal lobes that are almost equal in size.

Species list

The following is a list of species and subspecies accepted by the

Australian Plant Census The Australian Plant Census (APC) provides an online interface to currently accepted, published, scientific names of the vascular flora of Australia, as one of the output interfaces of the national government Integrated Biodiversity Information Syst ...

as at September 2020: * ''

Isotoma anethifolia ''Isotoma anethifolia'' is a small herbaceous plant in the family Campanulaceae and is endemic to eastern Australia. It has single, mostly white flowers in the leaf axils and slender stems. Description ''Isotoma anethifolia'' is an upright, pe ...

'' Summerh. –

NSW ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

QLD ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , establishe ...

* ''

Isotoma axillaris ''Isotoma axillaris'', commonly known as rock isotome or showy isotome, is a small herbaceous perennial in the family Campanulaceae. It usually has blue or mauve star-shaped flowers from September to May. It may also be called blue star, star flo ...

Lindl. John Lindley FRS (5 February 1799 – 1 November 1865) was an English botanist, gardener and orchidologist. Early years Born in Catton, near Norwich, England, John Lindley was one of four children of George and Mary Lindley. George Lindley ...

– NSW, QLD, VIC * ''

Isotoma fluviatilis ''Isotoma fluviatilis'', the swamp isotome or blue star creeper, is a small herbaceous perennial plant in the family Campanulaceae, native to Australia. Description This plant often forms a low growing mat. It is usually pubescent or sometimes ...

'' ( R.Br.)

F.Muell. Baron Sir Ferdinand Jacob Heinrich von Mueller, (german: Müller; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Vic ...

Benth. George Bentham (22 September 1800 – 10 September 1884) was an English botanist, described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studie ...

– NSW, QLD, SA, TAS,

VIC Vic (; es, Vic or Pancracio Celdrán (2004). Diccionario de topónimos españoles y sus gentilicios (5ª edición). Madrid: Espasa Calpe. p. 843. ISBN 978-84-670-3054-9. «Vic o Vich (viquense, vigitano, vigatán, ausense, ausetano, ausonense): ...

** ''Isotoma fluviatilis'' subsp. ''australis'' McComb ** ''Isotoma fluviatilis'' subsp. ''borealis'' McComb ** ''Isotoma fluviatilis'' (R.Br.) F.Muell. ex Benth. subsp. ''fluviatilis'' * '' Isotoma gulliveri'' F.Muell. – QLD * '' Isotoma hypocrateriformis'' (R.Br.) Druce – WA * '' Isotoma luticola''

Carolin Carolin is a given name. Notable people with the name include: Given name * Carolin Babcock (1912–1987), female tennis player from the United States *Carolin Bachmann Carolin Bachmann (born 3 September 1988 in Freiberg) is a German politician ...

– NT * ''

Isotoma petraea ''Isotoma petraea'', commonly known as rock isotome, is a small, herbaceous plant in the family ''Campanulaceae'' occurring in arid regions of Australia. It has single, purplish-blue flowers on smooth, slender branches from February to November. ...

'' F.Muell. – NSW, NT, QLD, SA, WA * '' Isotoma pusilla'' Benth. – WA * ''

Isotoma scapigera ''Isotoma scapigera'', commonly known as long-scaped isotome, is a small herbaceous plant in the family ''Campanulaceae'' native to Western Australia. The erect, annual herb typically grows to a height of . It blooms between September and Decem ...

'' (R.Br.)

G.Don George Don (29 April 1798 – 25 February 1856) was a Scottish botanist and plant collector. Life and career George Don was born at Doo Hillock, Forfar, Angus, Scotland on 29 April 1798 to Caroline Clementina Stuart and George Don (b.1756), p ...

– SA, WA * '' Isotoma tridens'' ( E.Wimm.) Lammers – NSW, VIC

References

{{Taxonbar, from=Q16054811 Campanulaceae genera