Niphidium crassifolium commonly known as the graceful fern is a species of fern

Fern

A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...

 in the Polypodiaceae

Polypodiaceae

Polypodiaceae is a family of polypod ferns, which includes more than 60 genera divided into several tribes and containing around 1,000 species. Nearly all are epiphytes, but some are terrestrial.-Description:...

 family found in Central and South America. It is predominantly an epiphytic, growing on other plants for example in the canopies of trees, but is occasionally grows on rocks

Epipetric

An epipetric plant, is one that is found growing on rocks. Many ferns fall into this category of plant habitat, including Asplenium . Epipetric plants are called Lithophytes....

 or on the ground, particularly at higher altitude. It has a rhizome

Rhizome

In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...

 from which many fine rootlets covered in dark reddish-brown scales grow. Together they form a root basket, which when growing on trees, helps to trap leaf litter and dust, forming a nutrient-rich soil which holds water. Its leaves are simple in shape, 13–85 cm (5.1–33.5 in) long and 3–5 cm (1.2–2 in) wide and when dry are covered by a wax-like film. The sori are round and large, occurring in single rows between veins at the far end of the leaf.

Taxonomy

Niphidium crassifolium was first described by Carl Linnaeus in 1753 as Polypodium

Polypodium

Polypodium is a genus of 75–100 species of true ferns, widely distributed throughout the world, with the highest species diversity in the tropics. The name is derived from Ancient Greek poly "many" + podion "little foot", on account of the foot-like appearance of the rhizome and its branches...

 crassifolium. In 1972, David B. Lellinger

David B. Lellinger

David Bruce Lellinger is an American botanist, specializing in ferns, working at the Smithsonian Institution in Washington, DC. He began work as a student assistant in 1960 and 1961. He was hired as full-time staff in 1963. He has for some years been the curator of pteridology at the...

 moved the species into the Niphidium

Niphidium

Niphidium is a genus of ferns in family Polypodiaceae. They are native to the Caribbean, Central America, and South America.- Species :* Niphidium albopunctatissimum, Lellinger.* Niphidium anocarpos, Lellinger....

genus. It can be difficult to distinguish from N. albopunctatissimum but this species has narrower leaves and is mostly found growing on rocks or on the ground and has a different range.

Distribution

Niphidium crassifolium is found in Central and South America, from Mexico in the North to Ecuador in the South and including Panama, Peru, Brazil, French Guiana, Guyana and the West Indies. It grows at altitudes up to 1100 metres (3,608.9 ft) above sea level and over a wide range of humidity. According to Thomas Croat, it is probably the most common fern found on Barro Colorado Island

Barro Colorado Island

Barro Colorado Island is located in the man-made Gatun Lake in the middle of the Panama Canal. The island was formed when the waters of the Chagres River were dammed to form the lake. When the waters rose, they covered a significant part of the existing rainforest, and the hilltops remained as...

, Panama (BCI). Niphidium crassifolium is known to grow on Socratea exorrhiza

Socratea exorrhiza

Socratea exorrhiza, the Walking Palm or Cashapona, is a palm native to rainforests in tropical Central and South America. It can grow to 25 meters in height, with a stem diameter of up to 17 cm. It has unusual stilt roots, the function of which has been debated. Many species of epiphyte have...

, occurring on 12% of individuals on BCI. It is also known to grow on Platypodium elegans

Platypodium elegans

Platypodium elegans or the graceful platypodium is a large leguminous tree found in the Neotropics that forms part of the forest canopy. It was first described by Julius Rudolph Theodor Vogel in 1837 and is the type species of the genus. The tree has been known to grow up to 30 metres in...

, Ceiba pentandra, Tabebuia guayacan and Anacardium excelsum.

Biochemistry

It uses crassulacean acid metabolism

Crassulacean acid metabolism

Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. The stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide...

 (CAM), where it stores some carbon dioxide produced by respiration

Cellular respiration

Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate , and then release waste products. The reactions involved in respiration are catabolic reactions that involve...

 at night and releases this for use in photosynthesis

Photosynthesis

Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

 the next day, but the overall contribution of this is small compared to true CAM plants such as cacti. If drought stressed, the contribution of CAM increases from 2.7% of total carbon fixation

Carbon fixation

In biology, carbon fixation is the reduction of carbon dioxide to organic compounds by living organisms. The obvious example is photosynthesis. Carbon fixation requires both a source of energy such as sunlight, and an electron donor such as water. All life depends on fixed carbon. Organisms that...

 to 10%. The production of gametophyte

Gametophyte

A gametophyte is the haploid, multicellular phase of plants and algae that undergo alternation of generations, with each of its cells containing only a single set of chromosomes....

s is determined by the light level rather than by a hormone

Plant hormone

Plant hormones are chemicals that regulate plant growth, which, in the UK, are termed 'plant growth substances'. Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells locally and, when moved...

.

Uses

It can be cultivated, being described as growing well in well drained soil under medium light. It is reported to be able to survive consecutive days of freezing temperatures, down to -7 C. In Northern Peru the fresh stem is used in traditional medicine to treat inflammation of internal organs.