''Tuberaria guttata'', the spotted rock-rose or annual rock-rose, is an annual plant of the Mediterranean region which also occurs very locally in

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

and

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

. The flowers are very variable with the characteristic spot at the base of the petal very variable in size and intensity of colour.

Description

''Tuberaria guttata'' is an

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 ...

that grows to tall. It has a rosette of basal leaves, each up to long and wide, but this rosette has normally withered by the time the plant is in flower. The stems bear 2–5 opposite pairs of leaves, and a few smaller leaves higher up, arranged alternately. The

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 ...

comprises around 12 flowers, in diameter. Each flower has five uneven sepals and five yellow petals usually with a dark red spot near the base. The flowers are cleistogamous, producing little

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

and no

nectar Nectar is a viscous, sugar-rich liquid produced by Plant, plants in glands called nectaries, either within the flowers with which it attracts pollination, pollinating animals, or by extrafloral nectaries, which provide a nutrient source to an ...

, and attracting few insect visitors, and the petals fall off after only a few hours. The centre of the flower houses around 20

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s and a single capitate stigma. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

of ''T. guttata'' is a capsule containing many seeds, each long.

Distribution and ecology

''Tuberaria guttata'' is widely distributed in the Mediterranean region, and has a continuous distribution along the French Atlantic coast as far as the

Channel Islands The Channel Islands are an archipelago in the English Channel, off the French coast of Normandy. They are divided into two Crown Dependencies: the Jersey, Bailiwick of Jersey, which is the largest of the islands; and the Bailiwick of Guernsey, ...

. Further north, its distribution is very patchy, being confined to a few localities on the west coasts of Ireland and Wales. The best-known of these populations is on the slopes of Holyhead Mountain in

Anglesey Anglesey ( ; ) is an island off the north-west coast of Wales. It forms the bulk of the Principal areas of Wales, county known as the Isle of Anglesey, which also includes Holy Island, Anglesey, Holy Island () and some islets and Skerry, sker ...

. These British populations mark the northernmost limit of the species' distribution. ''Tuberaria guttata'' was chosen by

Plantlife Plantlife is a wild plant conservation charity. , it manages 24 nature reserves around the United Kingdom. HM King Charles III is patron of the charity. History Plantlife was founded in 1989. Its first president was Professor David Bellamy ...

as the county flower of Anglesey in 2002. In

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, ''T. guttata'' has become naturalised in the foothills of the

Sierra Nevada The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primari ...

on the eastern edge of the

Sacramento Valley The Sacramento Valley is the area of the Central Valley of the U.S. state of California that lies north of the Sacramento–San Joaquin River Delta and is drained by the Sacramento River. It encompasses all or parts of ten Northern California ...

. In the Mediterranean region, ''T. guttata'' is common in arid habitats from woodlands to grasslands and roadsides. In the British Isles, it grows "in bare patches of thin, dry soil overlying hard igneous rock in open areas within wind-cut heath near the sea".

Taxonomy

''Tuberaria guttata'' was first described by

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

as "''Cistus guttatus''" in his 1753 work '. It was transferred to the genus '' Tuberaria'' by Jules Pierre Fourreau in 1868. The Welsh populations were described as a separate species in 1844 by

Jules Émile Planchon Jules Émile Planchon (21 March 1823 – 1 April 1888) was a French botanist born in Ganges, Hérault. He was a brother of Gustave Planchon who also studied medicinal plants. Biography After receiving his Doctorate of Science at the Universit ...

. He named the plants "''Helianthemum breweri''", after Samuel Brewer, who had discovered the population in 1726. This is now considered a synonym of ''T. guttata''.

References

External links

* {{Taxonbar, from=Q159449 Cistaceae Plants described in 1753 Taxa named by Carl Linnaeus