Platycerium andinum

Platycerium andinum Baker is an accepted naturally occurring species in Polypodiaceae.

John Gilbert Baker published P. andinum in 1891; the lectotype is Spruce 4739 from near Tarapoto, Peru, collected in 1855–1856.

The accepted native range is Peru to western Bolivia, making P. andinum the only Platycerium native to the Americas.

The core habitat is seasonally dry tropical forest in rain-protected valleys along the eastern Andean foothills, most commonly documented around 200–400 m with an exceptional record at 1,100 m.

In the Tarapoto dry forests, P. andinum is especially associated with Manilkara bidentata, whose rough bark and broad branching provide favorable establishment sites; other hosts also occur.

P. andinum grows in clusters or colonies and can form massive rings of multiple plants around a trunk or branch; colonial pups generally arise from roots.

Shield fronds are generally 40–60 cm long, exceptionally to 100 cm, with an erect upper portion usually divided into two equally long main lobes and containing water-storage tissue.

Foliage fronds are pendulous, 100 cm to more than 200 cm long, divide three to five times, and usually bear two or four elongated soral patches positioned medially rather than at the terminal tips.

Plastid phylogenomics places P. andinum as sister to the African P. angolense–P. stemaria lineage, with a split estimated around 10.6 million years ago and long-distance dispersal favored over continental drift.

P. andinum spores can germinate and produce gametophytes in sterile culture, although completion to a young sporophyte can be slow or condition-dependent.

Root-produced pups provide a biologically supported route for clonal division once a pup has its own viable growing point and roots.

The estimated late-Miocene split is far younger than the separation of South America and Africa, so transoceanic spore dispersal is the supported explanation.

Documented threats include logging and loss of large host trees, agricultural conversion, fire, land-use change, and ornamental collection within a narrow and fragmented dry-forest range.

Platycerium andinum has long, hanging fertile fronds densely covered with pale, star-shaped hairs. The hairs can clump together on new growth, giving it a soft, moss-like appearance.