Subordinate Taxa
Scientific Name:
Salvinia Ség., Pl. Veron. 3, 52 (1754)
Type Taxon:
Salvinia natans (L.) All.
Named in honour of Professor Antonio Maria Salvini (1633-1722), botanist and Greek scholar from Florence.

Aquatic ferns, free-floating.  Stems short, branching, hairy, lacking roots.  Leaves dimorphic, arranged in whorls of 3; each group comprising two floating, green, entire, foliar leaves, and one submerged, highly divided leaf appearing root-like; upper surface of foliar leaves bearing specialised water-repellent hairs; lower surface of foliar leaves and the submerged leaves bearing multicellular hairs.  Veins anastomosing without free included veinlets.  Sporocarps attached to the submerged leaves, subsessile or stalked, globose to ovoid; each sporocarp bearing either mega- or microsporangia.  Sporangia usually empty in NZ plants; when fertile (not NZ), megaspores solitary in each megasporangium; microspores 32–64 in each microsporangium.  Spores absent or aborted in NZ plants; when formed (not NZ) megaspores spheroidal, plain, perforate; microspores spheroidal, plain to rugulate.


10–12 species widespread in tropical regions, extending also into temperate areas, with two centres of distribution in Africa, and in South and Central America (Schneller 1990); some species have become tropical weeds.  One naturalised species in New Zealand.

Number of species and named hybrids in New Zealand within Salvinia Ség.
Exotic: Fully Naturalised1

x = 9 (Schneller 1990), the lowest base chromosome number known in ferns (Smith et al. 2006).


The taxonomy of neotropical species was outlined by Mitchell & Thomas (1972) and adopted by Tryon & Tryon (1982).  Following the initial investigation, Salvinia ×molesta was described as a new species (Mitchell 1972).  It belongs to a small group of South American taxa, including S. auriculata and S. biloba (syn. S. herzogii, see de la Sota 1995), in which the hairs at the end of the leaf papillae are joined at their distal ends.

Based on analysis of five different genes, Nagalingum et al. (2008) showed that Salvinia comprises two Eurasian and American groups, although only the American clade, which includes S. ×molesta, is strongly supported.

Plants of Salvinia are free-floating and capable of covering large areas of slow-moving or still water.  In New Zealand, sporocarps are rare and are usually empty when found, and reproduction is vegetative.  Spores of American species are illustrated by Tryon & Lugardon (1991).

Brownsey, P.J.; Perrie, L.R. 2015: Salviniaceae. In: Breitwieser, I; Heenan, P.B.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 10. Manaaki Whenua Press, Lincoln.
Christenhusz, M.J.M.; Zhang, X.-C.; Schneider, H. 2011: A linear sequence of extant families and genera of lycophytes and ferns. Phytotaxa 19: 7–54.
de la Sota, E.R. 1962: Contribución al conocimiento de las Salviniaceae neotropicales, III Salvinia herzogii nov. sp. Darwiniana 12: 499–513.
de la Sota, E.R. 1995: Nuevos sinónimos en Salvinia Ség. (Salviniaceae, Pteridophyta). Darwiniana 33: 309–313.
de la Sota, E.R. 2001: Sobre el tipo de Salvinia adnata (Salviniaceae, Pteridophyta). Boletín de la Sociedad Argentina de Botánica 36: 125–129.
Kramer, K.U.; Green, P.S. 1990: Pteridophytes and gymnosperms. Kubitzki, K. (ed.) The Families and Genera of Vascular Plants. Vol. 1. Springer-Verlag, Berlin.
Mitchell, D.S. 1972: The Kariba weed: Salvinia molesta. British Fern Gazette 10: 251–252.
Mitchell, D.S.; Thomas, P.A. 1972: Ecology of waterweeds in the Neotropics. UNESCO Technical Papers in Hydrology. Vol. 12. UNESCO, Paris.
Nagalingum, N.S.; Nowak, M.D.; Pryer, K.M. 2008: Assessing phylogenetic relationships in extant heterosporous ferns (Salviniales), with a focus on Pilularia and Salvinia. Botanical Journal of the Linnean Society 157: 673–685.
New Zealand Weed and Pest Control Society 1969: Standard common names for weeds in New Zealand. Editorial Services Ltd, Wellington.
Schneller, J.J. 1980: Cytotaxonomic investigations of Salvinia herzogii de la Sota. Aquatic Botany 9: 279–283.
Schneller, J.J. 1981: Chromosome numbers and spores of Salvinia auriculata Aublet s.str. Aquatic Botany 10: 81–84.
Schneller, J.J. 1990: Salviniaceae. In: Kramer, K.U.; Green, P.S. Pteridophytes and gymnosperms. Vol. 1. In: Kubitzki, K. (ed.) The Families and Genera of Vascular Plants. Springer-Verlag, Berlin.
Séguier, J.F. 1754: Plantae Veronenses. Vol. 3. Verona.
Smith, A.R.; Pryer, K.M.; Schuettpelz, E.; Korall, P.; Schneider, H.; Wolf, P.G. 2006: A classification for extant ferns. Taxon 55(3): 705–731.
Tryon, A.F.; Lugardon, B. 1991: Spores of the Pteridophyta. Springer-Verlag, New York.
Tryon, R.M.; Tryon, A.F. 1982: Ferns and allied plants. Springer-Verlag, New York.