Shoot Morphology of the Climbing Fern Lygodium (Schizaeaceae): General Organography, Leaf Initiation, and Branching

The Effects of Fire on Spore Viability of Lygodium microphyllum (Old World Climbing Fern)

“…2003;Madeira et al 2008;Mueller 1982aMueller , b, 1983Pemberton 1998;Wikstrӧm et al 2002). Recently, Christenhusz and Chase (2014) have reaffirmed its placement in Schizaeaceae on the basis of molecular phylogenetic analyses and suggest that Lygodium could comprise its own subfamily Lygodioideae Christenh., as sister to subfamilies Schizaeoideae Lindl., and Anemioideae C.Presl.…”

“…The genus was present in North America and Germany by the Late Cretaceous (Gandolfo et al 2000) and had substantial representation throughout the Cenozoic Era (Wikstrӧm et al 2002). Although considered a primitive fern, its extremely modified vegetative morphology indicates later functional specialization of the shoot, which is clearly differentiated into leaves and stem, as are seed plants, but in Lygodium the leaf takes on characteristics of the shoot in seed plants (Mueller 1982a). Earlier accounts of L. microphyllum sometimes referred to it as Lygodium scandens (L.) Swartz or Ugena microphylla Cav., and during the height of its importation and sale, it was apparently often confused with and sold as Japanese Climbing Fern (Lygodium japonicum (Thunb.)…”

“…Sw.), another exotic congeneric fern that has invaded central and northern Florida (Beckner 1968;Ferriter 2001. Although L. microphyllum and L. japonicum are closely related and morphologically similar, differences include pinnule shape, rhizome depth, and rhizome tolerance to freezing temperatures; L. japonicum's greater cold tolerance likely contributes to its current successful invasion of colder northern Florida (Hutchinson and Langeland 2014, Mueller 1982a, Van Loan 2006. In contrast to L. japonicum, the viability of L. microphyllum spores and gametophytes is greatly reduced by exposure to freezing temperatures, as shown by Hutchinson and Langeland (2014), possibly limiting its northward expansion.…”

“…Lygodium microphyllum is a homosporous fern composed of a dichotomously branching, protostelic rhizome with adventitious roots and indeterminate climbing leaves (fronds) (Mueller 1982a). The rhizome grows at, or just below, the soil surface and, once established, can withstand temporary inundation and variable water levels (Gandiaga et al 2009, Mueller 1982a, Volin et al 2004.…”

“…The rhizome grows at, or just below, the soil surface and, once established, can withstand temporary inundation and variable water levels (Gandiaga et al 2009, Mueller 1982a, Volin et al 2004. Leaves form dorsally on the rhizome, follow a single rank, and develop from a single cell produced by the apical meristem (Mueller 1982a). The primary leaves are determinate and usually less than 10 cm in height, while secondary leaves are indeterminate and twining, sometimes reaching over 30 m in length (Mueller 1982a).…”