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BFNA Title: Gymnocolea |
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Edit Level R Brum+ Gymnocolea - Jungermanniaceae XXX. GYMNOCOLEA (Dumortier) Dumortier, Rec. d'Obs. 17.
1835 * [Greek, gymno‑, naked and koleo‑,
female sheath, in reference to the large perianth, not concealed by bracts] Marie L. Hicks Jungermannia sect. Gymnocolea
Dumortier, Syll. Junger. Eur. 52. 1831
Plants creeping with ascending apices, mat forming or erect
when crowded, green to blackish‑brown or scorched in insolated sites. Stems
7‑‑8 cells in diameter, branching terminal, lateral or ventral intercalary,
from older stems, cortical cells thin‑walled, 20‑‑25 µm, little
differentiated from medullary;
rhizoids very sparce, scattered along ventral stem, colorless. Leaves
succubous‑oblique, bilobed, the lobes obtuse to rounded, occasionally acute,
often concave; leaf cells subisodiametric, small, 22‑‑30 µm; cuticle smooth,
occasionally slightly verruculose; walls without distinct trigones; oil
bodies smooth to slightly granulate. Underleaves absent or occasional and
small, of 1‑‑3 cells from narrow ventral merophytes of 2‑‑4 cells. Specialized
asexual propagation by detached inflated perianths that float on water;
gemmae absent or very rare, angular, brown, 1‑‑2 celled. Sexual
condition dioecious. Androecia
terminal, spicate, becoming intercalary, of ventricose bracts similar to
leaves but smaller; antheridia one per bract; stalk 1‑seriate. Gynoecia
terminal on main stem or branch, often with subfloral innovations; bracts
similar to leaves; bracteole absent; perianth exerted, inflated, smooth, the
mouth contracted; perigynium absent. Sporophyte seta cross section of 8
exterior cells and 4 interior cells; capsule ovoid, brown, valves 2 cells
thick, the walls with nodular thickenings; elaters 120‑‑200 × 6‑‑9 µm, 2‑spiral,
brown; spores 10‑‑18 µm, finely papillate, brown. Species 6 (2 in the flora); cool parts of the Northern
Hemisphere and South America. SELECTED REFERENCES
Schuster, R. M. 1969. The
Hepaticae and Anthocerotae of North America, Vol. II. New York. 1. Leaf lobes
with obtuse or rounded apices; gemmae absent; perianths inflated, easily
detached . . . 1.Gymnocolea inflata 1. Leaf lobes
with acute apices; gemmae rare; perianths uncommon, not easily detached . . . 2. Gymnocolea acutiloba 1. Gymnocolea inflata (Hudson) Dumortier, Rec. d'Obs. 17. 1835. Jungermannia inflata Hudson, Fl. Angl. ed. 2. 2: 511. 1778. Plants with shoots 5‑‑25 × 0.75‑‑1.2 mm, scattered among mosses or in crowded
mats, green in shade or brownish‑black in exposed sites. Stems
slender, 130‑‑300 µm, branching irregular, terminal or ventral
intercalary. Leaves distant to scarcely imbricate, spreading, flat or more
often concave, as long as wide or slightly longer, 400‑‑900 × 350‑‑800 µm,
2-lobed 1/4‑‑1/3, the sinus narrow, the lobes obtuse to rounded, entire;
median leaf cells 22‑‑27 × 25‑‑30 µm, marginal cells 20‑‑24 µm; cuticle smooth,
walls evenly thickened; trigones absent; oil bodies 4‑‑8 per cell, ovoid or
spherical, 3‑‑4 × 5‑‑6 µm, finely granulate. Underleaves
absent. Specialized asexual propagation by detached,
unfertilized, inflated perianths that float on water; gemmae absent. Androecial
bracts up to 8 pairs, contiguous, concave, 2-lobed. Gynoecia commonly
with subfloral innovations; bracts similar to leaves in shape, slightly larger;
perianths often present, exerted well above bracts, globose to oblong,
inflated, large compared to the size of the shoot; mouth contracted, dentate‑lobulate;
easily detached from stem. Igneous rock outcrops subject to at least periodic
seepage, often in direct sunlight; also around rock pools and in bogs; e, w,
nw Greenland; Miquelon; Alta., Ark., B.C., Man., Nfld., N.S., Nun., Ont.,
Que., Yukon; Alaska, Calif., Colo., Conn., Maine, Mass., Mich., Minn., N. C.,
N.H., N.J., N.Y., Oreg., Pa., S.Dak., Tenn., Vt., Wash., Wyo.; Europe; Asia
(Japan). The variety Gymnocolea
inflata var. heterostipa (Carrington & Spruce) K. Müller, a dubious taxon
with frequent small intercalary branches and small underleaves, has been
recognized from plants collected in East Greenland and Minnesota. This plant is doubtfully distinct and its
gametophytic differences may be an environmentally induced variation. In Europe, where the variety was first
recognized, no distinct limits have been found between this variety and the typical
form of Gymnocolea inflata. 2. Gymnocolea acutiloba (Schiffner) K. Müller, Rabenh. Krypto. Fl. 6: 745. 1910 Lophozia acutiloba Schiffner, Hedwigia 48: 187. 1909 Plants with shoots 10‑‑15 × 0.6‑‑0.9 mm, forming mats, green to brown or blackish. Stems
100‑‑180 µm, sparingly branched, the branches terminal, occasionally
intercalary. Leaves remote to slightly overlapping, nearly flat, ovate‑quadrate,
slightly longer than wide, 370‑‑600 x 320‑‑500 µm, 2-lobed 1/3‑‑1/2 , with a
narrow sinus and subacute to acute lobes ending in 1‑‑2 single cells; lateral
leaf margins often with a small tooth; leaf cells subquadrate, 22‑‑28 µm,
walls slightly thickened, often brownish; trigones not developed; oil bodies
3‑‑8 per cell, ovoid or spherical 4‑‑6 × 5‑‑8 µm, smooth or slightly granular. Underleaves
absent or vestigial, of small cilia or slime papillae. Specialized
asexual propagation usually absent or rarely by gemmae on margins of leaf
lobes, angular, 14‑‑18 µm, 2‑celled, brown.
Plants usually sterile. Gynoecia
with bracts similar to leaves in shape, larger; perianth rarely produced, not
easily detached, inflated, clavate, the mouth dentate. Igneous rock that are perhaps copper‑bearing, where
they may occur with other rare species such as Cephaloziella massalongoi
or Gymnomitrion concinnatum; w Greenland; Alaska,
Maine, Tenn.; Europe. |
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