Krypt. Fl. Brandenburg 2: 922. 1906. -- Hypnum loreum Hedw., Spec. Musc. 294. 1801. -- Hylocomium loreum (Hedw.) Bryol. Eur. fasc. 49–51. 1852.
Plants to 25 cm long, in pale-green or yellowish-green wefts with strongly reddened stems, irregularly branched. Leaves plicate and strongly falcate, closely foliate, to 5 mm, 2.5–3.5: 1, ovate lanceolate and gradually contracted to the narrow acumen. Margins plane or nearly so throughout, not at all decurrent, entire to serrulate at base, serrulate to serrate above. Median cells smooth, 5–6 µm wide, linear, about 8–12: 1, thick-walled with lumen: wall ratio 2–3: 1, strongly pitted. Median basal cells orange to red-brown, broader and shorter than adjacent, more distal cells, thick-walled with lumen: wall ratio about 1: 1. Alar cells essentially undifferentiated. Costa double with forks separate from base, symmetrically inserted in center of leaf base, with both forks extending above the middle. Paraphyllia absent. Juvenile leaves orbicular to ovate, serrate on margin, closely overlapping bud with first such leaf proximal to bud. Axillary hairs about 5-celled, to 150 µm with two basal cells brown and short, mostly offset from leaf insertion. Stem cross-section with a small central strand, without a hyaloderm, with a well marked stereome of pachydermous, pigmented cells, and with inner cortical cells larger and mostly rather thick-walled. Rhizoids very rarely produced, mostly on the tips of ultimate branchlets, to 25 µm in diameter at insertion, arising from area immediately lateral to alar cells at leaf insertions, red-brown, monopodially branched with branches few, short, smooth and rather thick-walled.
Dioicous with male plants similar to females. Perichaetia on old, prostrate axes, with bracts essentially ecostate, to 3.5 mm long, erect and clasping at base but abruptly contracted into the squarrose and narrow acumen. Vaginulum to 4 mm long as a result of extensive coelocaul development. Seta to 4 cm long, erect, redddish-brown, smooth. Capsule red-brown, inclined and arcuate, somewhat sulcate when dry, not strangulate. Urn to 2 mm, oblong to almost globose, asymmetric, 1.2–1.5: 1. Exothecial cells isodiametric to short rectangular, to 30 µm broad, in regular rows, with lumen: wall ratio 2–4: 1. Exothecium in cross-section showing thick outer and vertical walls but thin inner walls. Stomata phaneroporous, small and vertical pored, restricted to neck. Annulus present, not revoluble. Operculum conic, much shorter than urn. Exostome to 800 µm long, closely horizontally striate throughout, red-brown. Endostome segments lightly papillose, perforate along keel, about as long as exostome with basal membrane about 1/2 of total length. Cilia 1–3, lightly papillose, strongly appendiculate. Spores green, smooth to very lightly papillose, to 18 µm.
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