Macrothelypteris (H.Itô) Ching

Terrestrial ferns. Rhizomes short-creeping or suberect, scaly. Rhizome scales narrowly ovate, thickened at their bases, with marginal and superficial hairs. Fronds monomorphic. Stipes scaly and hairy. Laminae 2-pinnate to 3-pinnate-pinnatifid, or rarely 1-pinnate-pinnatifid (not NZ), herbaceous, proximal pinnae not reduced in size; aerophores lacking; abaxial surface of laminae bearing scales and/or hairs; scales pallid, narrow and with or without ciliate margins, or absent; hairs acicular and either unicellular or multicellular; glandular hairs absent; short-stalked spherical glands sometimes present. Veins free, branched in the pinnules and not reaching the margins. Sori small, often irregularly shaped, indusiate (NZ) or exindusiate (not NZ); paraphyses absent. Indusia tiny, glabrous or bearing short-stalked glands. Sporangia bearing short-stalked glands near the annulus, lacking hairs on the stalk. Spores monolete, minutely reticulate and with slight wings.

Allan (1961) included all indigenous New Zealand species of Thelypteridaceae within a broadly construed Thelypteris. However, Macrothelypteris is now widely recognised as a distinct genus of about 10 species in the Old World tropics and subtropics and the Pacific (Holttum 1969, 1971; Smith et al. 2006; Fawcett & Smith 2021). It is characterised by a short-creeping rhizome, rhizome scales which are narrow and thickened at their bases, often with marginal hairs, usually at least bipinnate laminae, veins in the pinnules which are branched and do not reach the margins, small sori with very small indusia, and sporangia that bear short-stalked glands near the annulus.

The base chromosome number in Macrothelypteris is x = 31 (Holttum 1971; Smith 1990; Fawcett & Smith 2021).