Two cytotypes and a new hybrid in Salvinia Séguier

Abstract

Two cytotypes (2n=4x=36 and 2n=6x=54) found in Salvinia minima Bak. are discussed, the first from Brazil and the second from Argentina. The hexaploid cytotype, presumably a hybrid between Salvinia minima and S. sprucei Kuhn, was collected from the Solimões River near Manaus, Brazil and from Trinidad. Discussing its intermediate morphology, the authors attemp to explain the hybridization as a result of the seasonal and sporadic occurrence of Salvinia sprucei in the Amazonian basin, assuming that the still unknown chromosome number of the latter species would correspond to the diploid level (2n=2x=18).

Salvinia (Salviniaceae) in southern and southeastern Brazil—including new taxa, new distribution records, and new morphological characters

“…Salvinia sprucei occurs in northern South America (Amazon region) and Central America. In 2001, Sota and Cassa de Pazos (2001) reported a hybrid between S. sprucei and the widespread S. minima, from Trinidad and northern Brazil. The hybrid clearly presents intermediate morphology, such as the sub-flabeliform laminae and the hair systems restricted to the distal 1/3 of laminae.…”

“…The hybrid clearly presents intermediate morphology, such as the sub-flabeliform laminae and the hair systems restricted to the distal 1/3 of laminae. Although Sota and Cassa de Pazos (2001) reported the hybrid, they did not describe it as a new taxon. We here describe it, honoring Sota.…”

“…We analyzed two materials of this hybrid: one from northern Brazil, from a place near those specimens studied by Sota and Cassa de Pazos (2001), and another from São Paulo, which was probably cultivated there. Salvinia minima does occur in southeastern Brazil, but S. sprucei definitely not.…”

Molecular characterization of the species Salvinia (Salviniaceae) from the upper Paraná River floodplain

“…The occurrence of interspecies hybrids, registered by Cook (1990) and Sota and Pazos (2001), is another complicating factor in species identification. The aggressive species S. molesta, originally identified as S. auriculata, has intermediate characteristics expected from a hybrid between S. biloba and S. herzogii, coupled to its possible great adaptability (Mitchell and Thomas, 1972;Schneller, 1990).…”