''Helosciadium'' × ''longipedunculatum'',

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

''Apium'' × ''longipedunculatum'', is a

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

plant in the umbellifer family (Apiaceae); the result of hybridisation between ''

Helosciadium repens ''Helosciadium repens'' commonly known as creeping marshwort, is a species of plant belonging to the Apiaceae family. It occurs in Western and Central Europe, being rare throughout its range. It grows in wetland areas where it does not have to co ...

'' (creeping marshwort) and '' Helosciadium nodiflorum'' (fool's water cress).

Discovery

The hybrid was first discovered by George Lawson in July 1845 at

Gullane Gullane ( or ) is a town on the southern shore of the Firth of Forth in East Lothian on the east coast of Scotland. There has been a church in the village since the ninth century. The ruins of the Old Church of St. Andrew built in the twelft ...

East Lothian East Lothian (; sco, East Lowden; gd, Lodainn an Ear) is one of the 32 council areas of Scotland, as well as a historic county, registration county and lieutenancy area. The county was called Haddingtonshire until 1921. In 1975, the histo ...

, Scotland, and two voucher specimens were deposited in the

herbarium A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study. The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...

of William Gardiner,

Dundee Dundee (; sco, Dundee; gd, Dùn Dè or ) is Scotland's fourth-largest city and the 51st-most-populous built-up area in the United Kingdom. The mid-year population estimate for 2016 was , giving Dundee a population density of 2,478/km2 or ...

. Following Gardiner's death in 1852 the specimens were transferred as part of a bequest to the British Museum, and shortly afterward (''ca.'' 1854) loaned to German botanist Friedrich W. Schultz, who described them as a new variety of ''Helosciadium nodiflorum'', var. ''longipedunculatum''. The variety was later (1906) described in further detail by Harry J. Riddelsdell and Edumund G. Baker, who examined a number of specimens from the original Gullane locality, as well as additional specimens from

Duddingston Loch Duddingston Loch is a lake, or freshwater loch, in Edinburgh. It is one of the last two remaining natural lochs within the city, the other being Lochend Loch. It is situated to the south of Holyrood Park and lies southwest of the village of Duddi ...

, Edinburgh, Scotland. While Riddelsdell did not consider var. ''longipedunuclatum'' to be of hybrid origin, during the course of the 20th century a number of eminent botanists (e.g.

Werner Rothmaler Werner Walter Hugo Paul Rothmaler (born 20 August 1908 in Sangerhausen, died 13 April 1962 in Leipzig) was a German botanist and from 1953 until 1962 head of the Institute for Agricultural Biology of the University of Greifswald. His areas of expert ...

, Clive Stace) suggested that it was the hybrid between ''H. repens'' and ''H. nodiflorum''. In 2014, plants matching ''H. nodiflorum'' var. ''longipedunculatum'' were collected at Port Meadow,

Oxfordshire Oxfordshire is a ceremonial and non-metropolitan county in the north west of South East England. It is a mainly rural county, with its largest settlement being the city of Oxford. The county is a centre of research and development, primarily ...

, England and a molecular analysis confirmed it as the hybrid ''H. repens'' × ''H. nodiflorum''. The original specimens are still housed in the Natural History Museum, London, under voucher number BM001144095, and the one situated to the left has been designated as the lectotype.

Description

Creeping perennial herb with slender stems and rooting at lower nodes. Leaves simply pinnate with 4 to 7 pairs of leaflets, which are

ovate Ovate may refer to: *Ovate (egg-shaped) leaves, tepals, or other botanical parts *Ovate, a type of prehistoric stone hand axe *Ovates, one of three ranks of membership in the Welsh Gorsedd *Vates In modern English, the nouns vates () and ovat ...

to broadly ovate, coarsely serrate and occasionally lobed. Flowering umbels are borne on peduncles, which are equal to or longer than the rays of the umbel, and subtended at the base by an involucre of 1 to 3 bracts. Ripe fruits broader than long.

References

{{DEFAULTSORT:Helosciadium longipedunculatum Apioideae Hybrid plants