SafePlants

River Swamp Wallaby-grass (Amphibromus fluitans)

River Swamp Wallaby-grass, scientifically known as Amphibromus fluitans, is an aquatic perennial grass also referred to as Floating Swamp Wallaby-grass.

Considerations for Pets

• This grass spreads by both underground and above-ground stems, which could make it attractive to pets who like to dig or chew on plants.
• The plant can grow to 1.3 meters tall, providing potential hiding places for small animals.

Taxonomy and Nomenclature

• Genus: Amphibromus
• Family: Poaceae (Grass family)
• Common Names: Swamp Wallaby Grass (general term for most Amphibromus species), River Swamp Wallaby-grass, Floating Swamp Wallaby-grass
• Synonyms: Helictotrichon neesii (Preferred Name)

Distribution and Habitat

• Most Amphibromus species are endemic to Australia.
• Specific locations mentioned include near Murrami, NSW; Mount Painter; Namadgi National Park; and Tuggeranong Hill.
• Grows in freshwater swamps, floodplains, riverbanks, and drains.

Morphological Characteristics

• Aquatic perennial with decumbent culms (aerial stems growing horizontally with tips turned up) that can reach 1 meter in length.
• Can grow up to 0.8 to 1.3 meters tall.
• Culms are erect, flattened to terete (cylindrical and tapering), and 1-3 mm wide.
• Leaf blades can be flat to inrolled.
• Flowering stems tend to be somewhat sprawling.
• Spreads by both underground and above-ground stems.

Ecological Role

• Flowers in response to rain or flooding.
• Provides habitat and potential cover for wildlife, such as the Swamp Wallaby.

Other Amphibromus Species Mentioned:

• Amphibromus archeri (Pointed Swamp Wallaby-grass)
• Amphibromus macrorhinus (Long-nosed Swamp Wallaby-grass)
• Amphibromus neesii (Southern Swamp Wallaby-grass)
• Amphibromus nervosus (Common Swamp Wallaby-grass, Veined Swamp Wallaby)
• Amphibromus pithogastrus (Plump Swamp Wallaby-grass, Swollen Swamp Wallaby-grass)
• Amphibromus scabrivalvis

Further Information

• Australian Plant Census
• Biodiversity Conservation Unit, Adelaide Region (Phone: (61 8) 8336)
• USDA-NRCS PLANTS Database
• Discover Life
• Species Profile and Threats Database (SPRAT) - http://www.environment.gov.au/cgi-bin/sprat/publicspeciesprofileanddistribution