Lomariopsidaceae

Defining Characteristics

• Terrestrial or epiphytic ferns, often climbing or scandent
• Fronds typically once- pinnate and dimorphic — fertile fronds with sori covering the entire underside of pinnae (acrostichoid)
• Rhizome long-creeping and climbing (some species climb tree trunks)
• Sporangia with vertical annulus, long-stalked
• Gametophytes in some species can persist as free-living, ribbon-like or thalloid forms (notably the aquarium plant Süßwassertang)
• Indusium absent; sori acrostichoid (covering entire fertile pinna surface)

Notable Genera

• Lomariopsis (the dominant genus)
• Thysanosoria
• Dracoglossum

Notes

A small family of primarily tropical ferns notable in the aquarium hobby because the persistent gametophyte of Lomariopsis cf. lineata is sold as 'Süßwassertang' (German: freshwater seaweed). This flat, liverwort-like organism is unusual — it is a fern gametophyte that reproduces vegetatively indefinitely without transitioning to the familiar leafy sporophyte stage. The sporophyte forms are climbing ferns found in tropical forests. Family placement has shifted under molecular phylogenetics; sometimes included within Dryopteridaceae.