''Wahlenbergia'' is a
genus of around 260 species of
flowering plants in the
family Campanulaceae. Plants in this genus are
perennial or
annual 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 ...
with simple leaves and blue to purple bell-shaped flowers, usually with five
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 ...
s lobes. Species of ''Wahlenbergia'' are found on all continents except
North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
, and on some isolated islands, but the greatest diversity occurs in the
Southern Hemisphere.
Description
Plants in the genus ''Wahlenbergia'' are annual or perennial herbs, rarely shrubs, and sometimes have
rhizome
In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...
s. The stems are erect, circular in cross section and have simple leaves. The leaves decrease in size up the stem and usually have small scattered teeth on their edges. The flowers are borne on the end of the stems, either singly or arranged in a
cyme. There are five
sepals that remain until the fruiting stage. 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 ...
s are blue to purple and are joined at their base to form a bell-shaped or funnel-shaped tube with five lobes. There are usually five
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, the
style is often branched at the tip and the fruit is a
capsule containing up to fifty seeds.
Taxonomy and naming
In 1814,
Heinrich Schrader used the name ''Wahlenbergia elongata'' but the name was a
nomen nudum
In taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published with an adequate descr ...
. The genus was first formally described in 1821 by
Albrecht Wilhelm Roth
Albrecht Wilhelm Roth (6 January 1757 – 16 October 1834) was a physician and botanist born in Dötlingen, Germany.
He studied medicine at the Universities of Halle and Erlangen, where he received his doctorate in 1778.
After graduation, he pra ...
and the description was published in Roth's book ''Novae Plantarum Species praesertim Indiae Orientalis''. Roth retained Schrader's name ''Wahlenbergia''.
The name honours
Göran Wahlenberg (a Swedish botanist who taught at
Uppsala University).
Distribution
The genus is widespread and species of ''Wahlenbergia'' are found on all continents except North America. The highest species diversity is in southern temperate countries, particularly
Africa and
Australasia and species are even found on oceanic islands. Four species are known from the island of
Saint Helena
Saint Helena () is a British overseas territory located in the South Atlantic Ocean. It is a remote volcanic tropical island west of the coast of south-western Africa, and east of Rio de Janeiro in South America. It is one of three constitu ...
, including the now extinct species ''
W. roxburghii''.
Wahlenbergia stricta
''Wahlenbergia stricta'', the Australian bluebell, tall bluebell or austral bluebell, is an Australian wildflower from the Campanulaceae family. It is considered the most commonly encountered of the Wahlenbergias. It is found in all Australian s ...
''
Image:Wahlenbergia violacea kz6.jpg, ''Wahlenbergia violacea
''Wahlenbergia'' is a genus of around 260 species of flowering plants in the family Campanulaceae. Plants in this genus are perennial or annual herbs with simple leaves and blue to purple bell-shaped flowers, usually with five petals lobes. Speci ...
''
Image:Wahlenbergia capensis.jpg, ''Wahlenbergia capensis
''Wahlenbergia capensis'', commonly known as the Cape bluebell, is a plant in the family ''Campanulaceae'' and is native to the Cape Province but has been introduced to Australia. It is an annual herb with up to four greenish blue, bell-shaped f ...
''
See also
*
List of ''Wahlenbergia'' species
References
{{Taxonbar, from=Q1511493
Campanulaceae genera