The Moss Families of the British Isles


L. Watson and M. J. Dallwitz




Gametophyte. Acrocarpous; forming tufts, or forming patches. Mature plants 5–60 mm high. The leaves lanceolate, or lingulate, or spathulate; spiral; usually more or less crisped when dry, or crisped when dry to not crisped when dry (sometimes only incurved); single-nerved. The leaf nerves extending beyond the middle of the leaf, but not to the tip to extending to the leaf tip; sometimes shortly excurrent (into a mucro), or not excurrent. Leaf blades not lamellate. Leaf blade apices conspicuously hyaline (E. alpina), or not hyaline. Leaf blade margins flat, or involute or incurved, or revolute or recurved (sometimes recurved near the base and inflexed above); entire or crenulate. The basal leaf cells longitudinally much elongated; narrowly rectangular; smooth. The walls of basal leaf cells straight. The angular cells not well differentiated. The mid-leaf cells more or less isodiametric, or more or less isodiametric to somewhat longitudinally elongated; quadrate, or hexagonal, or rounded; papillose (with numerous small papillae per cell). The walls of the mid-leaf cells fairly thick, or thin; straight.

Plants monoecious (usually), or dioecious (E. streptocarpa); usually autoecious. Plants gemmiferous (often, in E. streptocarpa, in the form of brown, filiform, branched axillary propagules), or not gemmiferous.

Sporophyte. Capsules exserted; erect; symmetrical; straight; sub-cylindric; without an externally conspicuous apophysis; smooth, or striate and becoming regularly furrowed when dry and empty; with an annulus, or without an annulus. Calyptra very large and covering the well-developed capsule (and persistent, extending below the base of the capsule in characteristic fashion); glabrous (glossy); symmetrical; not plicate; tearing irregularly (at the base, or fringed), or entire. Capsules with a peristome, or without a peristome (two Encalyptra species). The peristome when present, single, or double (and sometimes, the inner and outer peristomes are more or less fused). The peristome teeth when present, deeply cleft, or not deeply cleft (in E. streptocarpa); when present, thin, membranous, and transversely barred; when present, exteriorly with a fine longitudinal dividing line between the transverse bars. The inner peristome in E. streptocarpa shorter than the outer. The operculum rostrate to subulate. Setae long; straight; yellowish or red.

Ecology. Mesophytic, or xerophytic; occurring in mainly basic habitats. Mainly associated with basic rocks and cliffs or mortar in walls, often at high altitudes.

Cytology. Haploid chromosome number, n = 13, 14, 26, and 39.

British representation. 6 species. Encalyptra (Encalypta). Northern Scotland, southern Scotland, northern England, English Midlands, East Anglia, Wales, southeast England, central southern England, southwest England, Isle of Wight, and Ireland.

Classification. Class Bryopsida; Subclass Funariideae; Order Encalyptales.

Illustrations. • Encalyptra spp.: Dixon. • Encalyptra vulgaris Hedw.: Berkeley.

To view the illustrations with detailed captions, go to the interactive key. This also offers full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The moss families of the British Isles. Version: 21st June 2009.’.