Amblystegium varium (Hedw.) Lindb.

  • Authority

    Hedenäs, Lars. 2003. Amblystegiaceae. Fl. Neotrop. Monogr. 89: 1--107. (Published by NYBG Press)

  • Family

    Amblystegiaceae

  • Scientific Name

    Amblystegium varium (Hedw.) Lindb.

  • Type

    Type. U.S.A. Pennsylvania: Lancaster, Muhlenberg s.n. (lectotype, G, designated by Hedenas & Geissler, 1999).

  • Synonyms

    Hypnum sparsifolium Hampe, Hypnum campicola Müll.Hal., Amblystegium pulchellum Müll.Hal., Amblystegium jaffuelii Thér., Amblystegium varium var. arsenei Thér., Leskea varia Hedw., Hygroamblystegium varium (Hedw.) Mönk., Orthotheciella varia (Hedw.) Dixon

  • Description

    Species Description - Plants small or medium-sized; green, yellow green, or brownish. Stem irregularly or irregularly pinnately branched in one plane; central strand present, slender; pseudoparaphyllia lanceolate-ovate or occasional outer ones filamentose; paraphyllia rare, foliose, ovate-lanceolate; axillary hairs with l(-2)-celled upper part, this hyaline when young. Stem leaves 0.6-2.1 mm long, patent to spreading, more erect when dry, straight or weakly curved, ovate or ovate-triangular, narrowing rather abruptly to acumen, slightly concave, short- and narrow-decurrent; acumen long, the apex acuminate; margin finely denticulate or entire (occasionally partially denticulate); costa single, ending ± high up in acumen, 29.5-58.0(-77.5) µm wide at base; median laminal cells (15.0-)17.0-65.0 × 6.0-12.0(-14.0) µm, thin-walled and eporose or incrassate and slightly porose; alar cells rectangular or quadrate, the basal cells rectangular to elongate-rectangular, not or hardly widened; alar group ovate or broadly ovate and often indistinctly delimited along basal margin of leaf. Inner perichaetial leaves narrowing gradually to acuminate apex, plicate. Seta 17-45 mm long, smooth; capsule curved, horizontal; operculum conical. Exostome outside cross-striolate in lower part; border widened at middle of teeth. Endostome cilia as long as segments or almost so. Spores 12.5-16.5 µm, finely papillose.

  • Discussion

    Amblystegium varium has been reported from Mexico, Guatemala, Panama, Bermuda, Haiti, Dominican Republic, Peru, and Bolivia (e.g., Bartram, 1949; Buck, 1998; Delgadillo et al., 1995; Menzel, 1992). This is the first report of A. varium from Colombia and Brazil. The species also occurs in northernmost Argentina within the Flora Neotropica area. I have not been able to confirm the reports of this species from Hispaniola, and at least some material originally identified as A. varium from this island belongs to A. fluviatile. Amblystegium varium is variable, but is mostly easily recognized by its small to medium-sized plants, its relatively narrow costa (mostly < 58.0 µm wide near base, rather than >60.0 µm as in A. tenax) that ends ± high up in the acumen, an acuminate leaf apex (rather than obtuse or rarely acute as in A. fluviatile), and relatively well-differentiated alar groups with rectangular to long-rectangular basal cells. Amblystegium serpens is smaller (stem leaves 0.5-1.0 mm vs. 0.6-2.1 mm in A. varium), and usually has a shorter stem leaf costa (mostly ending around midleaf); its leaf margins are more distinctly denticulate; and its alar cells are more short-rectangular. Amblystegium humile has undifferentiated alar cells, a shorter costa than A. varium, and leaves that are markedly constricted in their basal part. To avoid possible confusion with Cratoneuron fllicinum or Leptodictyum riparium, see the notes after these species.

    Distribution and Ecology: Mexico (5202385 m a.s.l.), Guatemala (1585-1800 m), Bermuda (altitude unknown), Colombia (3200-3350 m), Ecuador (2135-2745 m), Peru (915-2315 m), Brazil (550900 m), Bolivia (altitude unknown), and Argentina (altitude unknown). Also known from southern S America. Widespread in temperate N America and Eurasia, reaching into subtropical parts; additionally in N Africa and Australia. Found in various wet or moist habitats, both in open habitats and in moist to swampy forests, on rocks, soil, rotten wood; often on the shores of brooks or rivers; also in anthropogenic habitats, such as cement blocks, roadside cuttings, irrigation ditches, or on shaded ground in gardens.

  • Distribution

    Mexico North America| Guanajuato Mexico North America| México Mexico North America| Morelos Mexico North America| Nuevo León Mexico North America| Oaxaca Mexico North America| Puebla Mexico North America| Tamaulipas Mexico North America| Veracruz Mexico North America| Zacatecas Mexico North America| Guatemala Central America| Baja Verapaz Guatemala Central America| Quiché Guatemala Central America| Huehuetenango Guatemala Central America| Bermuda South America| Colombia South America| Nariño Colombia South America| Ecuador South America| Pichincha Ecuador South America| Peru South America| Arequipa Peru South America| Cusco Peru South America| Lima Peru South America| San Martín Peru South America| Brazil South America| Minas Gerais Brazil South America| Paraná Brazil South America| Rio Grande do Sul Brazil South America| Santa Catarina Brazil South America| São Paulo Brazil South America| Bolivia South America| La Paz Bolivia South America| Argentina South America| Jujuy Argentina South America|