Pteridaceae E.D.M.Kirchn.

Gemma Bramley, Anna Trias-Blasi & Richard Wilford (2023). The Kew Temperate Plant Families Identification Handbook. Kew Publishing Royal Botanic Gardens, Kew

Recognition

Characters of similar families: Dennstaedtiaceae: true indusium present. Dryopteridaceae (Polypodiaceae–Dryopteridoideae): sori usually with an orbiculate to reniform indusium. Aspleniaceae (Aspleniacae–Asplenioideae): true indusium present (an elongated flap running along veins); scales always clathrate and often iridescent. Athyriaceae (Aspleniacae–Athyrioideae): true indusium present; mostly terrestrial ferns growing in the understorey below trees and shrubs. Polypodiaceae: scales often peltate, leaves articulated to a persistent stipe base.

Morphology General Habit

Small to large terrestrial and lithophytic ferns

Vegetative Multiplication Rhizomes

Rhizomes creeping, ascending or erect, and in most cases scaly

Morphology Leaves

Fronds mostly monomorphic, occasionally dimorphic- Lamina pinnatifid to 6 times pinnate, more rarely peltate (e.g. Adiantum pedatum); petiole with usually 1 or 2 vascular bundles, glabrous, hairy or scaly, glossy brown to black or duller, grey to green; veins free or anastomosing, never with included veinlets Whole fronds sometimes able to curl up entirely in the dry season (subfamily Cheilanthoideae). Ultimate segments sometimes very reduced, often petiolate, and occasionally with a crosswise groove or articulation line

Morphology Leaves Leaf lamina

Abaxial side of the lamina sometimes covered with a white, silver or golden powder or farina or with many hairs or scales

Morphology Reproductive morphology Sori

Sori in many species are fused into coenosori that follow either the veins in the middle of the lamina or the lamina margin, continuously or discontinuously The sori can also form smaller patches on vein tips (e.g. Anogramma) or at the bottom of the sinuses between two lobes; when marginal, the sori are often protected by a recurved portion of the lamina known as false indusium (e.g. Adiantum, Pteris)

Morphology Reproductive morphology Sporangia

Sporangia on a long stalk

Morphology Reproductive morphology Spores

Spores mostly brown, yellowish, or colourless, mostly tetrahedral-globose and trilete, rarely ellipsoid and monolete.

Ecology

Found from mountains to tropical forests.

Distribution

A large, diverse family with 5 subfamilies (Parkerioideae, Cryptogrammoideae, Pteridioideae, Vittarioideae and Cheilanthoideae), 53 genera and over 1000 species recognised by the Pteridophyte Phylogeny Group in 2016. Christenhusz et al. (2017) listed only 45 genera before lumping all cheilanthoid ferns into Hemionitis (Christenhusz et al. 2018), leaving 32 genera.

Note

Small to large ferns with creeping to erect rhizomes. Sporangia in patches or fused in coenosori that are located along the veins centrally or marginally on the ventral side of the frond. True indusia missing, with the sori often protected by the in-rolled lamina margin instead (pseudo-indusium).