Citation: L., Sp. Pl. 1062 (1753).

Derivation: Greek ophis, a snake; glossa, a tongue; alluding to the shape of the fruiting spike.

Synonymy: Not Applicable

Common name: Adders tongue.

Description:
Rhizome short, erect or prostrate, unbranched, glabrous; sterile frond segment simple, entire, more or less fleshy, glabrous, with reticulate venation, erect, spreading or pendulous; fertile segment arising from the sterile blade or below, stalk fleshy; spike with 2 rows of large embedded sporangia; sporangia opening by transverse slits.

Distribution:  About 26 species, probably 5 in Australia.

Biology: No text

Key to Species:

1. Stipe bases not persistent; rhizome with a few brittle dark-brown roots; sterile lamina 0.8-3.5 cm long	O. lusitanicum 1.
1. Stipe bases persistent; rhizome with numerous wiry pale yellow-brown roots; sterile lamina 3.5-6 cm long	O. polyphyllum 2.

Author: Not yet available

Image source: fig. 17j in J.P. Jessop and H.R. Toelken Ed. 1986. Flora of South Australia (4th edn).