1. Salvinia Séguier, Pl. Veron. 3: 52. 1754.
Floating fern, water spangles [for A. W. Salvini (1633--1729), an Italian botanist]
Stems with many multicellular hairs. Leaves horizontally spreading. Blades of floating leaves green and pubescent abaxially (on side away from water). Sporocarps borne on chainlike or cymelike organs or submerged leaves; sporangia indehiscent, dispersed as units when sporocarps decay.
Species ca. 10 (1 in the flora): mostly tropical, North America, Mexico, West Indies, Central America, South America, Eurasia, Africa including Madagascar.
Leaf development in Salvinia is unique. The upper side of the floating leaf, which appears to face the stem axis, is morphologically abaxial (J. G. Croxdale 1978, 1979, 1981).