Ophioglossales
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 Botrychium lunaria
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Ophioglossales (lit. 'snake-tongue-plant') are a small group of pteridophyte plants. Traditionally they are included in the division Pteridophyta, the ferns, originally as a family and later as the order Ophioglossales. In some classifications this group is placed in a separate division, the Ophioglossophyta. Recent molecular systematic studies have shown the Ophioglossales to be most closely related to the Psilotales and a recent classification by Smith et al. (2006) places these two orders together in class Psilotopsida.
Ophioglossales contains a single family, Ophioglossaceae, which in some classifications is sometimes split into two or three families, the adders'-tongues, Ophioglossaceae, and the moonworts and grape-ferns, Botrychiaceae. The distinct species Helminthostachys zeylanica is sometimes given its own family, Helminthostachyaceae. Most recent treatments of the Ophioglossoids have treated all of them in Ophioglossaceae.
The plants have short-lived spores formed in sporangia lacking an annulus, and borne on a stalk that splits from the leaf blade; and fleshy roots. Many species only send up one frond or leaf-blade per year. A few species send up the fertile spikes only, without any conventional leaf-blade. The gametophytes are subterranean. The spores will not germinate if exposed to sunlight, and the gametophyte can live some two decades without forming a sporophyte.
The genus Ophioglossum has the highest chromosome counts of any known plant.
[edit] References and external links
- Smith, A. R., K. M. Pryer, E. Schuettpelz, P. Korall, H. Schneider & P. G. Wolf. 2006. A classification for extant ferns. Taxon 55(3):705–731.
- Ophioglossophyta images
