Ophioglossaceae

Abstract

The Ophioglossaceae is a family of Pteridophyta, in the order of Ophioglossales, consisting of about 4 genera with approximately 80 species, worldwide distributed. Plants are perennial, mostly terrestrial, rarely epiphytic, usually small and fleshy, lacking sclerenchyma, often erect or seldom pendulous. Rhizomes are short, erect, with several fleshy roots, lacking root hairs. Fronds are dimorphic, with sterile and fertile fronds, both from one common stipe. Sterile fronds are simple, margins entire, 1–2-leaved, rarely many-leaved, lanceolate or ovate, reticulately veined, midveins inconspicuous. Fertile fronds are petiolate, from common stipe or sterile leaf base. Sporangia are with thick wall, large style, bilateral arrangement along apophyses, embedded, forming linearly spicate, and transversely dehiscent. Spores are tetrahedral, reticulate on out walls. Only one species, Ophioglossum vulgatum Linn., belonging to Ophioglossum genus, is illustrated in the chapter.