× ''Beruladium procurrens'' is an

intergeneric hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

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

Berula erecta ''Berula erecta'', known as lesser water-parsnip or cutleaf waterparsnip or narrow-leaved water-parsnip, is a member of the carrot family. Growing to around tall, it is found in or by water. It is widespread across much of Europe, Asia, Austral ...

'' (lesser water parsnip) and ''

Helosciadium nodiflorum ''Helosciadium nodiflorum'' (synonym: ''Apium nodiflorum''), fool's watercress, is a flowering plant found in ditches or streams, as well as fresh and brackish-water wetlands native to western Europe. It is not poisonous to humans but it could be ...

'' (fool's water cress).

Discovery

In July 1979 Max Walters collected an unidentified plant from

Chippenham Fen Chippenham Fen and Snailwell Poor's Fen is a biological Site of Special Scientific Interest south-east of Fordham in Cambridgeshire, England. It is a Nature Conservation Review site, Grade I, a Ramsar wetland site and a Special Area of Conservat ...

, Cambridgeshire, England; it resembled ''H. nodiflorum'', but grew as a floating mass in a fen ditch with small, pedunculate umbels rising above the water surface. Later that year, the specimen was exhibited as a living plant at the annual

BSBI The Botanical Society of Britain and Ireland (BSBI) is a scientific society for the study of flora, plant distribution and taxonomy relating to Great Britain, Ireland, the Channel Islands and the Isle of Man. The society was founded as the Botani ...

exhibition meeting at the British Museum in London. An initial putative determination of ''H. repens'' was made, but as the plants were found to produce poor

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

and did not develop ripe fruits a hybrid origin was deemed more likely, possibly ''H. repens'' x ''H. nodiflorum''. Later suggestions included a depauperate example of ''B. erecta'', which can be confused with ''H. nodiflorum'' in the vegetative state, or else an intergeneric hybrid between the two. The original material was cultivated for a number of years in Cambridge University Botanic Garden, but this stock is no longer extant, nor was material placed in Cambridge University Herbarium (CGE). However, the original collections made by Walters are present as dried specimens in the University of Leicester Herbarium (LTR), presumably retained after being sent to then herbarium director

Tom Tutin Thomas Gaskell Tutin, FRS (21 April 1908 – 7 October 1987) was Professor of Botany at the University of Leicester and co-author of ''Flora of the British Isles'' and ''Flora Europaea''. Earlier life Tutin was born on 21 April 1908 in Kew, Surre ...

for determination. Walters XBeruladium LTR

Plants considered to be the same as those collected by Walters in 1979 still occur on Chippenham Fen and, in 2014, Alan Leslie reexamined the plants and sent them for molecular and cytogenetic analysis at the University of Leicester, which revealed a previously unknown intergeneric hybrid between ''B. erecta'' and ''H. nodiflorum''.

Chromosome number

The original Walters' material and the 2014 collection from Chippenham Fen are both 2n = 20, which is consistent with an intergeneric hybrid between ''B. erecta'' (2n = 18) and ''H. nodiflorum'' (2n = 22)

Distribution

East Anglia (particularly Cambridgeshire and

Suffolk Suffolk () is a ceremonial county of England in East Anglia. It borders Norfolk to the north, Cambridgeshire to the west and Essex to the south; the North Sea lies to the east. The county town is Ipswich; other important towns include Lowes ...

). Notable sites: Chippenham Fen and

Carlton Marshes Carlton and Oulton Marshes is a 151 hectare nature reserve in Lowestoft in Suffolk. It is managed by the Suffolk Wildlife Trust. Carlton Marshes is part of the Sprat's Water and Marshes, Carlton Colville Site of Special Scientific Interest, th ...

Description

Creeping perennial herb that roots at most nodes. Leaves simply pinnate with up to 5 pairs of leaflets, which are ovate to broadly ovate. Petioles without petiolar ring characteristic of ''B. erecta''. Flowering umbels, typically small, are borne on peduncles, which vary from very short to longer than the rays of the umbel, and subtended at the base by an involucre of (1)2-3 bracts. Sterile; ripe fruit absent.

References

{{DEFAULTSORT:Beruladium procurrens Apiaceae Hybrid plants Intergeneric hybrids