Amblystegium serpens (Hedw.) Schimp.
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Authority
Hedenäs, Lars. 2003. Amblystegiaceae. Fl. Neotrop. Monogr. 89: 1--107. (Published by NYBG Press)
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Family
Amblystegiaceae
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Scientific Name
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Type
Type. Europe s.n. (lectotype, G, designated by Hedenäs & Geissler, 1999).
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Synonyms
Amblystegium kochii Schimp., Amblystegium juratzkanum Schimp., Hypnum serpens L. ex Hedw.
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Description
Species Description - Plants minute or mostly small; green, yellow green, or brownish. Stem irregularly or irregularly pinnately branched in one plane; central strand present; pseudoparaphyllia narrow-triangular to triangular; paraphyllia absent; axillary hairs with l(-2)-celled upper part, this hyaline when young. Stem leaves 0.51.0 mm long, erect to patent, straight, ovate or ovate-triangular, narrowing gradually or rather abruptly from far below to apex, slightly concave, not decurrent; apex acuminate; margin denticulate to finely denticulate (at least partially); costa single, extending 40-85% of way up leaf or sometimes less, 27.5-46.0 µm wide at base; median laminal cells 14.5-52.5(-63.0) × 7.5-12.5 µm, slightly incrassate, eporose; alar cells quadrate or short-rectangular, the basal cells short-rectangular or rectangular, not inflated; alar group indistinctly delimited, broadly ovate or transverse-triangular, reaching from leaf margin ca. 65% of distance to leaf middle at insertion. Inner perichaetial leaves narrowing slightly below acuminate apex, plicate. Seta 14-23 mm long, smooth; capsule curved, horizontal; operculum conical. Exostome outside cross-striolate in lower part; border widened at middle of teeth. Endostome basal membrane height 40-45% of total endostome height; cilia as long as segments or almost so. Spores 9.0-18.5 µm, finely papillose.
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Discussion
Amblystegium serpens was reported from Mexico, Guatemala, Haiti, Colombia, Ecuador, and Peru (e.g., Bartram, 1949; Buck, 1998; Churchill, 1994; Churchill & Linares, 1995; Crum & Anderson, 1981; Delgadillo et al., 1995; Menzel, 1992; Steere, 1948). The present reports of this species from Bermuda and Bolivia seem to be the first ones. I have seen no correctly identified material from Guatemala. The specimens reported by Bartram (1949) as A. serpens are Conardia compacta, and the one reported as A. juratzkanum is A. varium. Of the two specimens mentioned from Haiti by Buck (1998), one is A. pseudosubtile, and the other belongs to another species. The latter (Haiti, Dept, de la Grand’anse, Massif de la Hotte, Buck 9118, NY) has leaves varying in shape from ovate to lanceolate, narrowing gradually upward from far below; the leaf margins are almost entire; and the alar cells are differentiated to almost undifferentiated. This material does not fit within the normal variation of any Amblystegiaceae species known from the area, and could possibly even be a modification of some Brachytheciaceae species. Amblystegium serpens is usually recognized by its relatively small size, a relatively weak costa ending 40-85% of the way up the leaf, at least partially denticulate or finely denticulate stem leaf margins, and relatively short rectangular alar cells. Relative to Amblystegium subtile and A. pseudosubtile, which have straight and erect capsules with highly conical to rostrate opercula and endostomes with vestigial or absent cilia, Amblystegium serpens has spore capsules that are curved and horizontal; opercula that are conical; and endostomes with cilia. The differences between A. serpens and A. varium are discussed under the latter.
Distribution and Ecology: Mexico (23002590 m a.s.L), Bermuda (altitude unknown), Colombia (2800 m), Ecuador (1675 m), Peru (altitude unknown), and Bolivia (2740-3810 m). Also known from southern S America. Widespread in temperate N America and Eurasia, reaching into subtropical areas; in addition known from N and E Africa and Australia. Found in both mineral-poor and mineral-rich habitats, on moist rocks and soil, on shores of brooks, sometimes in anthropogenic habitats (such as lawns); outside the area often on rotten wood or tree bases.
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Distribution
Mexico North America| Baja California Mexico North America| Distrito Federal Brazil South America| Veracruz Mexico North America| Zacatecas Mexico North America| Bermuda South America| Orange Walk Belize Central America| Colombia South America| Nariño Colombia South America| Ecuador South America| Tungurahua Ecuador South America| Peru South America| Bolivia South America| Cochabamba Bolivia South America| La Paz Bolivia South America|