Classification
Class
Polypodiopsida
Subclass
Polypodiidae
Order
Schizaeales Schimp.
Family
Lygodiaceae M.Roem.
 Subordinate Taxa
 Nomenclature
Scientific Name:
Lygodium Sw., J. Bot. (Schrader) 1800(2): 7, 106 (1801), nom. cons.
Type Taxon:
Lygodium scandens (L.) Sw.
Etymology:
From the Greek lygodes (twining, pliant), a reference to the climbing fronds.
 Description

Climbing ferns. Rhizomes creeping, bearing septate hairs. Fronds monomorphic, not articulated to rhizome; juvenile fronds of determinate growth; adult fronds twining and climbing with a wiry rachis of indeterminate growth. Stipes glabrous or hairy. Pinnae arising alternately on rachis, dividing pseudo-dichotomously with a dormant bud in the axil, glabrous or sparsely hairy. Fertile and sterile segments often markedly dimorphic. Veins free or reticulate without free included veinlets. Sporangia borne individually in two rows on marginal lobes of the fertile segments, not in sori, each covered by an antrorse subtending indusium-like flange, asymmetrically ovoid, attached laterally, with the annulus horizontal around the outward-pointing apex, dehiscing by a vertical longitudinal slit; spores maturing ±simultaneously; 128–256 spores per sporangium. Homosporous; spores trilete, tuberculate or verrucate, lacking chlorophyll.

 Distribution

A genus of about 30 species distributed throughout the tropics and subtropics, extending to temperate parts of Japan, China, eastern USA, New Zealand and southern Africa; about nine species in tropical and temperate America, four in Africa, 15 in south-east Asia, four in Australia and seven in the Pacific. One species endemic to New Zealand.

 Biostatus
Indigenous (Non-endemic)
Number of species in New Zealand within Lygodium Sw.
CategoryNumber
Indigenous (Endemic)1
Total1
 Cytology

The base chromosome number in Lygodium is given as x = 29, 30 by Smith et al. (2006) with n = 29, 30, 58, and 60, and 2n = 56, 112, 116 and 120 recorded by Kramer (1990).

 Bibliography
Brownsey, P.J.; Given, D.R.; Lovis, J.D. 1985: A revised classification of New Zealand pteridophytes with a synonymic checklist of species. New Zealand Journal of Botany 23(3): 431–489.
Brownsey, P.J.; Perrie, L.R. 2014: Lygodiaceae. In: Breitwieser, I; Heenan, P.B.; Wilton, A.D. (ed.) Flora of New Zealand — Ferns and Lycophytes. Fascicle 2. Manaaki Whenua Press, Lincoln.
Brownsey, P.J.; Smith-Dodsworth, J.C. 2000: New Zealand ferns and allied plants. Edition 2. David Bateman, Auckland.
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.
Kramer, K.U. 1990: Schizaeaceae. 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. 258–263.
Large, M.F.; Braggins, J.E. 1991: Spore atlas of New Zealand ferns and fern allies. SIR Publishing, Wellington.
Pichi Sermolli, R.E.G. 1977: Tentamen Pteridophytorum genera in taxonomicum ordinem redigendi. Webbia 31: 313–512.
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.
Swartz, O.P. 1801: Genera et species filicum ordine systematico redactarum. Journal für die Botanik (Schrader) 1800(2): 1–120.