Links to genera Ferns and Horsetails (Monilophytes) Clubmosses and Quillworts (Lycophytes)
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| Asplenium | Generally small to medium ferns, although some tropical species are larger. Usually tufted, with a short, creeping rhizome. Rhizome scales latticed (clathrate). Leaves usually tough, shiny on the upper surface; sori elongated along veins of leaf-segments; indusium following the same form as the sorus, sometimes becoming so crowded they appear to cover the whole underside of the leaf-segment. European species are mostly plants of rocky situations, and several have made the transition to man-made habitats such as walls.
Hartstongue Fern and Rustyback Fern are sometimes included in Asplenium and sometimes separated out as separate genera - Phyllitis and Ceterach. Here I have included them in Asplenium. Their status (and that of some other genera not occurring in these islands sometimes included in Asplenium, such as Camptosorus and Schaffneria) is the subject of much recent research and debate. The hybrids between scolopendrium and other Asplenium species, often referred to by the hybrid genus name of x Asplenophyllitis, are here also included in Asplenium.
About 600-700 species worldwide. 11 species in Britain and Ireland (using the more inclusive definition of Asplenium), one of which occurs only in Britain, another only in Ireland.
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