Platycerium grande

Platycerium grande is an accepted naturally occurring species in Polypodiaceae, native to the Philippines and Sulawesi.

Acrostichum grande A.Cunn. ex Hook. was published in 1830, and John Smith published the accepted combination Platycerium grande in 1841.

Long treated as a Philippine endemic, P. grande was documented from wild populations in Nantu Forest, Gorontalo, Sulawesi, in a peer-reviewed paper published in 2020.

In Sulawesi, documented plants grew 20–30 m above the ground on the first or second major branches of very large forest trees at 300–400 m elevation.

Shield fronds measure approximately 80–110 by 90–180 cm, curve outward with age, and form a deep debris-catching basket with an upper crown divided three to five times.

Mature fertile fronds are symmetrical and produced in pairs; each frond divides into two equal main lobes, each bearing one broad semicircular spore patch, while repeatedly forked side branches hang below.

Mature P. grande has two approximately equal spore patches on a symmetrical fertile frond, unlike the single patch of P. superbum and the asymmetrical fertile fronds of P. holttumii and P. wandae.

P. grande is a solitary staghorn fern and does not normally form the basal offsets used to divide colonial species.

Philippine research raised P. grande from spores through the gametophyte stage to young sporophytes and reported young sporophytes about nine weeks after transfer to potting medium.

Juvenile leaf explants produced green globular bodies in vitro; the best activated-charcoal treatment averaged 264.3 sporophytes per dish, and 94% of plantlets survived acclimatization.

A 2024 plastid phylogenomic study strongly supported P. grande as the sister species of P. holttumii, with that pair sister to P. superbum and P. wandae.

The Philippines lists P. grande as Critically Endangered in Category A of DENR Administrative Order 2026-20. Separately, the 2020 Sulawesi study estimated fewer than 50 individuals in its known study population and proposed Critically Endangered under criterion D for that regional population.