Family: Amblystegiaceae |
Plants: small to large, green, yellow-green, yellowish, or brownish. Stems: sparsely and irregularly branched to ± pinnate, ± in one plane; hyalodermis absent, central strand present; paraphyllia absent; rhizoids or rhizoid initials on stem or abaxial costa insertion, rarely forming tomentum, slightly or occasionally strongly branched, smooth; axillary hair distal cells 1â3, hyaline. Stem: leaves erect-spreading, spreading, or sometimes squarrose, straight or falcate, ovate or broadly so, ovate-lanceolate, triangular, rounded-triangular, or cordate, not plicate, 0.9â6.4 à 0.4â1.6 mm; base not or hardly decurrent (narrowly decurrent in D. cardotii); margins plane, entire, slightly sinuate, or slightly denticulate, limbidia absent; apex long-acuminate to acute, acumen gradually differentiated or distinctly set off, plane or furrowed; costa double and short, single and long, or sometimes excurrent; alar cells differentiated, short-rectangular to short-linear, strongly inflated, hyaline, widest cells 17â32 µm wide, region distinct, transversely triangular or ± quadrate, reaching from margin (25â)40â100% distance to costa at insertion; medial laminal cells linear; marginal cells 1-stratose. Sexual: condition autoicous [synoicous] or dioicous. Capsule: horizontal, cylindric, curved; peristome perfect; exostome margins entire or slightly dentate distally; endostome cilia 2â4, well developed, nodose or distally sometimes appendiculate. Spores: 11â32 µm. Distribution: Nearly worldwide.
Discussion: Species 10 (7 in the flora).
Drepanocladus is found in more or less mineral- and nutrient-rich habitats. Differences between members of Drepanocladus and those of Campyliadelphus and Campylophyllum are discussed under 6. Campyliadelphus; characters separating Drepanocladus from 7. Campylium are mentioned under Campylium. The genus Calliergidium has been distinguished from Drepanocladus by its acute to obtuse leaf apices. However, the type of this genus, C. bakeri (Renauld) Grout, is a synonym of Drepanocladus aduncus, and Calliergidium is thus a synonym of Drepanocladus. Drepanocladus is widely distributed in the Holarctic region, in the temperate regions of the southern hemisphere, and in higher mountains in tropical and subtropical areas.
In the following key, as well as in the species descriptions, the ratios between the laminal cell and leaf sizes should be based on measurements in 8â10 adjacent stem leaves. The total size ranges should be searched for, and the median values of these should be used for the calculations of the ratios.
The name Drepanocladus sendtneri (Schimper ex H. Müller) Warnstorf has been used in the American literature, but this species is apparently restricted to Eurasia and Africa. It is distinguished from D. sordidus by a different ratio of medial laminal cell length (/um) to leaf length (mm), 17.9â24.4 (23.3â36.5 in D. sordidus).
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