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| The moss families (Bryophyta, Musci) of Britain and Ireland |
Tail-mosses.
~Thuidiaceae
Gametophyte. Pleurocarpous; forming tufts, or forming patches (the primary stems stoloniform, the secondary stems more or less erect and irregularly branched). Paraphyllia present, or absent. The leaves of main stems and branches markedly different in form (those on the primary stems smaller and different in shape). The leaves neither sphagnoid nor leucobryoid. The leaves ovate to narrowly lanceolate (sometimes deltoid), or lingulate; spiral; single-nerved. The leaf nerves extending beyond the middle of the leaf, but not to the tip. Leaf blade apices obtuse, or pointed; apiculate, or not apiculate; apically rounded, or apically acute to acuminate. Leaf blade margins narrowly revolute or recurved, or flat; entire, or denticulate to dentate (or crenulate). Leaf blades not conspicuously bordered. The basal leaf cells somewhat longitudinally elongated to longitudinally much elongated; papillose. The angular cells clearly differentiated to not well differentiated. The mid-leaf cells more or less isodiametric to somewhat longitudinally elongated; hexagonal to rounded; 1- or 2–3 papillose. The walls of the mid-leaf cells thick; straight.
Plants dioecious.
Sporophyte. Capsules exserted; erect; symmetrical; sometimes slightly curved, or straight; sub-cylindric, or ellipsoid to ovoid; without an externally conspicuous apophysis; with an annulus, or without an annulus. Calyptra symmetrical; splitting down one side. Capsules with a peristome. The peristome single, or single to double. The peristome teeth not grouped; not deeply cleft; not perforated; thin, membranous, and transversely barred; exteriorly with a fine longitudinal dividing line between the transverse bars. The inner peristome when present, reduced to rudimentary; shorter than the outer; with a basal membranous ring; with elongated “processes” (these short, and irregular at least in A. viticulosus); without cilia (or with rudiments only). The operculum conical to rostrate. Setae long to short, sometimes scarcely raised above the branches; straight; straw-coloured in A. viticulosus.
Ecology. Occurring in basic habitats (commonly), or neutral pH conditions, or acid conditions (?). On rocks, logs, tree bases or tree trunks, commonly in basic habitats.
Cytology. Haploid chromosome number, n = 11 (in A. longifolius and A. viticulosus).
Representation in Britain and Ireland. 3 species. Anomodon. Northern Scotland, southern Scotland, northern England, English Midlands, East Anglia, Wales, southeast England, central southern England, southwest England, Isle of Wight, and Ireland (A. viticulosus being the most generally distributed, being often common in basic habitats at low altitudes).
Classification. Class Bryopsida; Subclass Bryideae; Order Hypnales.
Illustrations. • Anomodon attenuatus, A. longifolius and A. viticulosus: Dixon. ANOMODONTACEAE: H, Anomodon longifolius (Brid.) Hartm.; I, Anomodon attenuatus (Hedw.) Hüb.; J, Anomodon viticulosus (Hedw.) Hook. & Tayl.
From Dixon (1924), the unscaled screen display approximately doubling the magnifications given with his individual figures. 1, leaf, or stem leaf where these differ; 2, branch-leaf; 3, perichaetial leaf; 4, perigonial leaf; 5, capsule; 6, peristome; 7, calyptra; 8, spores; 9, inflorescence; 10, gemmae; 11, paraphyllia; 12, stoma of capsule; *, plant, or part of one. Qualifications: a, apex; b, base; c, cells at one third from the apex; cv, ventral aspect of cells; cd, dorsal aspect of cells; bc, basal cells; x, section. • Anomodon, with Helodium and Thuidium: Berkeley. ANOMODONTACEAE: 6, Anomodon veticulosus (Hedw.) Hook. & Tayl.; a, leaf; b, capsule; c; part of peristome, from the inside. THUIDIACEAE: 4, Thuidium tamariscinum (Hedw.) Br. Eur.; a, leaves; b, capsule. HELODIACEAE: 5, Helodium blandovii (Web. & Mohr) Warnst.; a, stem leaf from above; b, stem leaf from below, showing paraphylla; c, capsule; d, branch leaf.
From Berkeley (1863, Plates 8 and 13). The approximate 1 cm scale applies to the whole plant (habit) illustrations only.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, 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. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The moss families (Bryophyta, Musci) of Britain and Ireland. Version: 5th August 2019. delta-intkey.com’.
