''Tmesipteris truncata'' (aka ''Tmesipteris oblanceolata'') is a fern ally

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to eastern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. It is commonly called a Fork Fern. The habitat of this primitive plant is under waterfalls, or in

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

gullies or

rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...

s. It is often found growing on the base of the King Fern. Usually seen as an

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

lithophyte Lithophytes are plants that grow in or on rocks. They can be classified as either epilithic (or epipetric) or endolithic; epilithic lithophytes grow on the surfaces of rocks, while endolithic lithophytes grow in the crevices of rocks (and are also ...

, but it may also appear as a terrestrial plant. It is found as far south as

Mount Dromedary Gulaga, dual-named as Mount Dromedary and also referred to as Mount Gulaga, is mountain located in the south coast region of New South Wales, Australia. It rises above the village of Central Tilba and is within the Gulaga National Park. At its ...

. The stems are 15 to 30 cm long, mostly unbranched. Three or four grooves are at the base. The leaves grow shorter at the base, also shorter at the apex of the stems. Leaves are narrow linear to oblong in shape; 15 to 25 mm long, 2 to 5 mm wide. The midvein of the leaf ends in a thin point. Synangia are 3 to 5 mm long. The specific epithet ''truncata'' refers to the leaf tops, which appear abruptly cut off.Les Robinson - Field Guide to the Native Plants of Sydney, page 303 This plant first appeared in scientific literature in 1810 as ''Psilotum truncatum'' in the '' Prodromus Florae Novae Hollandiae'', authored by the prolific Scottish botanist, Robert Brown. On 31 May 2024, ''Tmesipteris oblanceolata'' was reported to have been found to contain the largest known eukaryotic

genome In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...

, with 160 billion

base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

s, by comparison more than 50 times larger than the human genome.

References

{{Taxonbar, from=Q7810769 Psilotaceae Flora of New South Wales Flora of Queensland Epiphytes Plants described in 1810

See also

References