Amblystegium subtile (Hedw.) Schimp.

  • Authority

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

  • Family

    Amblystegiaceae

  • Scientific Name

    Amblystegium subtile (Hedw.) Schimp.

  • Type

    Type. Germany s.n. (lectotype, G, designated by Hedenäs & Geissler, 1999).

  • Synonyms

    Serpoleskea subtilis (Hedw.) Loeske, Platydictya subtilis (Hedw.) H.A.Crum

  • Description

    Species Description - Plants minute; green or yellow green. Stem irregularly branched in one plane; central strand present, slender; pseudoparaphyllia ovate or narrow-ovate; paraphyllia absent; axillary hairs with 1-2-celled upper part, this hyaline when young. Stem leaves 0.4-0.6 mm long, erect-patent, straight or slightly homomallous, ovate or triangular-ovate, narrowing gradually from far below to apex, constricted at insertion, slightly concave, not decurrent; apex acuminate; margin entire or finely denticulate; costa single, extending 30-50% of way up leaf or sometimes less, to 21.0 µm wide at base; median laminal cells 14.5-42.0(-50.0) × 6.5-12.5 |iim, slightly incrassate, eporose; alar cells transverse-short-rectangular or quadrate or especially toward insertion short-rectangular, not inflated; alar group somewhat indistinctly delimited, triangular or ovate, extending upward along margin and inward all the way or almost to costa. Inner perichaetial leaves narrowing gradually or abruptly to acuminate apex, smooth or almost so; costa long, ending in lower acumen. Seta 5-8 mm long, smooth; capsule straight, erect or slightly inclined; operculum highly conical to short-rostrate. Exostome outside cross-striolate in lower part; border not widened at middle of teeth. Endostome cilia absent or vestigial. Spores 10.0-14.0(-16.5) µm, finely papillose.

  • Discussion

    This is the first report of Amblystegium subtile from S America (cf. Churchill & Linares, 1995; Delgadillo et al., 1995). Because A. C. V. Schott collected in Colombia (Vegter, 1986), there is at present no immediate reason to suspect that the specimen and/or label have been confused with material from other areas of the world. The species is recognized by its small size, relatively short seta, straight and erect or almost erect capsule, highly conical to short-rostrate operculum, and the lack of well-developed endostome cilia. The species could only be confused with A. pseudosubtile among the species treated here, and the differences between these species are treated under the latter.

    Crum & Anderson (1981: p. 1145), Nyholm (1965: p. 495).

  • Distribution

    Colombia (altitude unknown). Widespread in temperate N America and Eurasia. Found on tree bases, stumps, sometimes on rotten logs.

    Colombia South America|