Ophioglossaceae
English: Snake-tongue-plants; Adder's-tongue family; Grapeferns; Eusporangiate ferns.
Clades: Ophioglossidae; Pteridophyte
habitat: temperate and tropical
Botany
Ferns; terrestrial.
Roots: fleshy.
Leaves: usually fleshy; turn brownish or reddish during colder months.
Spores: short-lived; not germinating if exposed to sunlight.
Sporangia: lacking an annulus; borne on a stalk that splits from the leaf blade.
Gametophyte can live some two decades without forming a sporophyte.
Typical
• mostly only a single fleshy leaf at a time.
• gametophytes are subterranean; rely on fungi for energy.
• eusporangia, larger, contain more spores, and have thicker walls than Instead of the leptosporangia typical of most ferns
• sporophylls, spore-bearing leaves, are divided into 2 distinct, the sporophore, which produces sporangia and has a greatly reduced and modified blade, and the rest of the leaf, the trophophore.
Taxonomy
Ophioglossaceae were originally treated as a family and later as the separate order Ophioglossales. Some placed themplaced in a separate division, Ophioglossophyta. Molecular phylogenetic studies have shown the Ophioglossales to be closely related to the Psilotales, and both are placed in the class Ophioglossidae or Psilotopsida. Older treatments recognized segregate families within the Ophioglossales, such as Botrychiaceae for the moonworts and grape ferns and Helminthostachyaceae for Helminthostachys, but modern treatments combine all members of the order into the single family Ophioglossaceae.
Genera
Mankyuoideae
◦ Mankyua
Ophioglossoideae
◦ Cheiroglossa
◦ Ophioderma
◦ Ophioglossum
Helminthostachyoideae
◦ Helminthostachys
Botrychioideae
◦ Botrychium
◦ Botrypus
◦ Japanobotrychum
◦ Sahashia
◦ Sceptridium