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BFNA
Title: Prasanthus |
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Gymnomitriaceae - Prasanthus xxx. PRASANTHUS Lindberg in Kgl. Sv. Vetensk. Akad. Handl. 23 (5): 62. 1989 • Greek prason, onion, plus anthos, flower Won Shic Hong Plants ca. 0.5 mm wide, forming dense prostrate mats. Stem a subterranean rhizome, ca. 5--10 mm, with numerous rhizoids. Leaves transversely inserted, scalelike, elliptical; cell walls thick and colorless; lobes shallowly 2-lobed 0.1--0.2 of their length, broadly triangular, entire or shallowly emarginate at the apex; oil bodies usually absent. Underleaves minute, 0.1--0.2 size of leaves, ovate-elliptical, unlobed to 2-lobed. Sexual condition paroicious. Specialized asexual reproduction absent. Antheridia axillary, male bracts similar to leaves, 1--3-androus, antheridial stalk 2-seriate. Gynoecia terminal on main stem, bulbous, bracts in several pairs, bearing slime papillae. Perianth absent. Perigynium fleshy, cup-like, densely rhizoidous. Capsule ovoid, wall 2-stratose. Elaters 6--8 m m wide. Spores 12--14 m m. Species 1 (1 in the flora): European Alps and High Arctic regions of the Northern Hemisphere. SELECTED REFERENCES Hedderson, T. A., L. Söderström and G. R. Brassard. 2001. Hepaticae of the Torngat Mountains, northern Labrador, Canada. Lindbergia 26: 143--156. Schuster, R. M. 1974. Prasanthus Lindb. & Arn. In: R. M. Schuster, 1966--1993. Hepaticae and Anthocerotae of North America, New York. Vol. 3. pp. 157--166. Schuster, R. M. and N. Konstantinova. 1996. Studies on the distribution of critical arctic/subarctic Hepaticae with special reference to taxa found in Russia. Lindbergia 21: 26--48. 1. Prasanthus suecicus (Gottsche) Lindberg Kgl. Sv. Vetensk-Akad. Handl. 23 (5): 62. 1889 Gymnomitrium suecicum Gottsche Fl. Danica 16: 20. 1871 Plants with aerial shoots 2--6 ´ 0.5--0.7 mm, whitish-green to grayish-green. Stem subterranean rhizome to 1 cm, branches occasionally leafless, 150--500 m m wide, stolons elongated, densely rhizoidous, rhizoids brownish. Lateral leaves transverse, imbricate, elliptical, 450--600 ´ 450--850 m m; lobe margins entire; cell shape variable, marginal cells 10--15 m m, median cells 15--20 ´ 20--25 m m, basal cells 20--60 m m, surface smooth, cell walls thickened, trigones small and not bulging. Underleaves occasionally present on subterranean stem, ovate-semicircular, margins entire. Gynoecial bracts closely imbricate, connate at base, bracteoles lanceolate. Archegonia 10--12. Calyptra purplish-red. Seta ca. 5 mm. Capsule wall exterior layer with nodular thickenings, interior layer with semiannular thickenings. Elaters 2-spiraled, reddish-brown. Spores finely papillose, reddish. Bare glacial soil; Greenland; Nfld. (Laborador, T. A. Hedderson et al. 2001), Que. (R. M. Schuster and N. Konstantinova (1996); Europe (Austria, Finland, Italy, Norway, Russia, Sweden), Asia (Siberia). This is a species of Greenland, the European Alps, and High Arctic regions generally. |
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