''Acrosorus'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s in the family

Polypodiaceae Polypodiaceae is a Family (biology), family of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family includes around 65 genus, genera and an estimated 1,650 species and is placed in the order Polypodiales, suborder ...

, subfamily

Grammitidoideae Grammitidoideae is a subfamily of the fern family Polypodiaceae, whose members are informally known as grammitids. It comprises a clade of about 750 species. They are distributed over higher elevations in both the Old World, Old and New World. T ...

, according to the

Pteridophyte Phylogeny Group The Pteridophyte Phylogeny Group (PPG) is an informal international group of systematic botanists who collaborate to establish on the classification of pteridophytes ( lycophytes and ferns) that reflects knowledge about plant relationships discove ...

classification of 2016 (PPG I). It is known from the Philippines,

Malesia Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalayan and Australasian realms. It is a phytogeographical floristic region in the Paleotropical kingdom. It was first recognized as a distinct region ...

, Thailand, and the Pacific islands.

Description

Members of the genus have radially symmetric (rather than flattened)

rhizome In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and Shoot (botany), shoots from its Node (botany), nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from ...

s, covered with hairless scales of uniform color. Their leaves may be partly cut, into lobes, or fully divided into pinnae. Their veins are at most a few times forked, and lack

hydathode A hydathode is a type of pore, commonly found in vascular plants, that secretes water through pores in the epidermis or leaf margin, typically at the tip of a marginal tooth or serration. Hydathodes occur in the leaves of submerged aquatic plant ...

s. Each lobe or pinna of a fertile leaf bears a single

sorus A sorus (: sori) is a cluster of sporangia (structures producing and containing spores) in ferns and fungi. A coenosorus (: coenosori) is a compound sorus composed of multiple, fused sori. Etymology This Neo-Latin word is from Ancient Greek � ...

near the tip; the edges of the lobes or pinnae are rolled under and fused near the tip to protect the sorus. Leaf hairs may be single

seta In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae, ...

e (bristles), single catenate hairs (consisting of chains of cells), or branched catenate hairs, with setae for branches.

Taxonomy

The genus was created by Edwin Copeland in 1906, to accommodate a group of ferns similar to '' Prosaptia'' and until then classified in '' Davallia''.

Species

, the ''Checklist of Ferns and Lycophytes of the World'' accepted the following nine species: *'' Acrosorus friderici-et-pauli'' (Christ) Copel. *''Acrosorus pectinatus'' Parris ined. *'' Acrosorus reineckei'' (Christ) Copel. *'' Acrosorus schlechteri'' Christ *'' Acrosorus sclerophyllus'' (Alderw.) Parris *'' Acrosorus streptophyllus'' (Baker) Copel. *'' Acrosorus subtriangularis'' (Alderw.) Parris *''Acrosorus tenuis'' Parris ined. *''Acrosorus vallatus'' Parris ined.

References

{{Taxonbar, from=Q5656847 Polypodiaceae Fern genera