Regnellidium

Regnellidium
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Salviniales
Family:	Marsileaceae
Genus:	Regnellidium Lindm.
Type species
Regnellidium diphyllum Lindm.
Species
R. diphyllum Lindm. †R. upatoiensis Lupiaet al.

Regnellidium is a monotypic genus of ferns of family Marsileaceae.^[1]

The single living species, Regnellidium diphyllum, the two-leaf water fern, is native to southeastern Brazil and adjacent regions of Argentina. It resembles its relatives from the genus Marsilea, but has 2-lobed leaves (rather than 4). This fern is sometimes grown in aquaria.

A fossil assigned to the species Regnellidium upatoiensis has been found in Cretaceous deposits of the eastern United States.^[2]

The genus name of Regnellidium is in honour of Anders Fredrik Regnell (1807–1884), a Swedish physician and botanist.^[3] It was first described and published in Ark. Bot. Vol.3 (Issue 6) on page 2 in 1904.^[1]

References

1. "Regnellidium Lindm. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 3 November 2021.
2. Lupia, R.; Schneider, H.; Moeser, G. M.; Pryer, K. M.; Crane, P. R. (2000). "Marsileaceae Sporocarps and Spores from the Late Cretaceous of Georgia, U.S.A". International Journal of Plant Sciences. 161 (6): 975–988. doi:10.1086/317567. S2CID 16981770.
3. Burkhardt, Lotte (2018). Verzeichnis eponymischer Pflanzennamen – Erweiterte Edition [Index of Eponymic Plant Names – Extended Edition] (pdf) (in German). Berlin: Botanic Garden and Botanical Museum, Freie Universität Berlin. doi:10.3372/epolist2018. ISBN 978-3-946292-26-5. Retrieved 1 January 2021.

Other sources

• Mabberley, D. J. (1997). The Plant-Book. Cambridge University Press.