''Archigrammitis'' 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

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 ...

and Polynesia.

Description

The

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 are dorsiventral (having distinct upper and lower surfaces) with stipes closely spaced attached in two rows. The stipes are jointed and have phyllopodia at the base. The rhizome scales have hairy edges, and are of uniform color and usually glossy. The leaf blades are undivided, usually bearing branched veins and more than one row of sori on either side of the

costa Costa may refer to: Biology * Rib (Latin: ''costa''), in vertebrate anatomy * Costa (botany), the central strand of a plant leaf or thallus * Costa (coral), a stony rib, part of the skeleton of a coral * Costa (entomology), the leading edge of th ...

. They always have unbranched hairs, while many species have branched hairs with a single gland at the apex. Some species have

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, some of which are cretaceous (leaving a lime deposit on the leaf around them). The

sporangia A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many ot ...

bear one to two (occasionally as many as six) stiff, simple straight hairs without glands at the tip of the sporangium. Parris observed that the genus resembles '' Prosaptia'' in bearing phyllopodia at the stipe bases, but lacks the clathrate rhizome scales of that genus. The presence of simple, stiff hairs on the sporangium is shared with '' Oreogrammitis'' and '' Radiogrammitis''.

Taxonomy

The genus was first described by Barbara Parris in 2013 to receive some of the species of the genus ''

Grammitis ''Grammitis'' (dwarf polypody) is a genus of ferns in the family Polypodiaceae, subfamily Grammitidoideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). It had formerly been placed in the family Grammitidacea ...

'', which as then circumscribed was artificial and contained a number of disparate lineages. The name "''Archigrammitis''" means "chief ''Grammitis''", referring to the size of the fronds, ''A. friderici-et-pauli'' being the largest member of ''Grammitis'' under the former circumscription.

Species

, the ''Checklist of Ferns and Lycophytes of the World'' accepted the following seven species: *'' Archigrammitis demissa'' (Parris) Parris *'' Archigrammitis friderici-et-pauli'' (Chris) Parris *'' Archigrammitis marquesensis'' (Parris) Parris *'' Archigrammitis ponapensis'' (Copel.) Parris *'' Archigrammitis samoensis'' (Baker) Parris *'' Archigrammitis solomonensis'' Parris *'' Archigrammitis tahitiensis'' (C.Chr.) Parris , the genus had not yet undergone phylogenetic study.

References

{{Taxonbar, from=Q17197971 Polypodiaceae Fern genera