Scouleria aquatica

Hooker in T. Drummond

in T. Drummond, Musc. Amer., 63. 1828,.

Synonyms: Scouleria muelleri Kindberg
Treatment appears in FNA Volume 27. Treatment on page 313.

Stem-leaves ligulate to lanceolate, (2.8–) 3–5 × 0.8–2.5 mm, margins 1-stratose or partially (rarely fully) 2-stratose, serrate distally; basal laminal cells isodiametric to shortly rectangular or juxtacostal cells linear to long-rectangular, 15–36 × 10–12 µm; medial and distal laminal cells 10–25 µm; marginal laminal cells similar to the medial or appearing differentiated, darker and walls thicker, 1-stratose to partially to nearly entirely 2-stratose. Peristome present.


Habitat: Aquatic habitats, banks or bed of streams and rivers, on rock
Elevation: low to high elevations (0-1900 m)

Distribution

V27 427-distribution-map.gif

Alta., B.C., N.W.T., Yukon, Alaska, Calif., Idaho, Mont., Oreg., Wash., Wyo., Asia (Russia: Amur Region), Asia (Siberia)

Discussion

The present concept of Scouleria aquatica is broad, encompassing several forms. Virtually all the variation is found in the gametophyte. Leaves vary in size and in particular marginal differentiation: 1-stratose with cells similar or slightly thicker and darker in color, to partially or nearly fully 2-stratose to near the leaf apex. Smaller plants are found in the northern range of the species (and also in Russia). Further studies, particularly molecular, could very well differentiate some of these populations as distinct taxa (at the subspecific or specific level).

Selected References

None.

Lower Taxa

None.
... more about "Scouleria aquatica"
Steven P. Churchill +
Hooker in T. Drummond +
long-rectangular +
decurrent +
cucullate +
spherical;obovoid +
thin-walled +  and thick-walled +
linear;long-rectangular +
large +  and small +
10um;12um +
ovoid +  and cylindrical +
expanding +
Alta. +, B.C. +, N.W.T. +, Yukon +, Alaska +, Calif. +, Idaho +, Mont. +, Oreg. +, Wash. +, Wyo. +, Asia (Russia: Amur Region) +  and Asia (Siberia) +
low to high elevations (0-1900 m) +
Aquatic habitats, banks or bed of streams and rivers, on rock +
ovatelanceolate +
not +  and projecting +
oblong-lanceolate +
2-stratose +  and 1-stratose +
apiculate +, mammillate +  and low-conic +
terminal;subterminal +
rounded +, acute +  and ovate +
concave +  and ovate +
in T. Drummond, Musc. Amer., +
papillose +
1/3 +  and 1/2 +
granulate +
0.28 cm2.8 mm <br />0.0028 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
lanceolate +
0.8mm;2.5mm +
elongate +
4 cm40 mm <br />0.04 m <br /> (10 cm100 mm <br />0.1 m <br />) +
dioicous +, sexual +  and asexual +
long-rectangular +
Scouleria muelleri +
Scouleria aquatica +
Scouleria +
species +
loose;compact +
compressed +
differentiated +
thicker +
brown +  and black +