Fissidens appalachensis

R. H. Zander

Bryologist 72: 406, figs. 1–8. 1969,.

Treatment appears in FNA Volume 27. Treatment on page 344. Mentioned on page 332, 336.

Plants to 13 × 2–4 mm. Stem unbranched and branched; axillary hyaline nodules weak or absent; central strand weak. Leaves as many as 22 pairs, ligulate to oblong-lanceolate, obtuse-mucronate to acute, to 4 × 0.3–0.5 mm; dorsal lamina narrowed proximally, ending at insertion or slightly before; vaginant laminae 1/2–2/3 leaf length, equal in proximal leaves, unequal in distal leaves, minor lamina ending between margin and costa or rounded and ending on or near costa; margin entire but sometimes serrulate distally, limbate on all laminae, limbidium confluent at apex or ending a few cells before, limbidial cells 2-stratose to 5-stratose; costa percurrent or ending in mucro, bryoides-type; laminal cells 1-stratose to irregularly 2-stratose, smooth, slightly bulging, firm-walled, irregularly hexagonal, many somewhat elongate, 10–16 µm, juxtacostal and basal-cells of vaginant laminae somewhat larger, quadrate to oblong. Sexual condition rhizautoicous or synoicous; perigonia and perichaetia on elongate stems. Sporophytes 1–2 per perichaetium. Seta 4–4.5 mm. Capsule theca exserted, erect, radially symmetric to slightly inclined, bilaterally symmetric, 0.6–0.85 mm; peristome bryoides-type; operculum 0.4 mm. Calyptra not seen. Spores 14–25 µm.


Habitat: Crevices and surfaces of rocks submerged in swiftly flowing but usually shallow water, sometimes partially emergent

Discussion

Fissidens appalachensis, restricted to rapidly moving water, is distinguished by its habitat and strong limbidium. It is most likely to be confused with an expression of F. bryoides that is usually found on wet rocks and stones along the edges of streams, but which differs in its smaller size and weaker limbidium that at times can be partially or completely absent. Laminal cells in size and shape, vaginant laminae, sexuality, thecae, and peristomes in both taxa are similar.

Selected References

None.

Lower Taxa

None.

"/2" is not declared as a valid unit of measurement for this property.

... more about "Fissidens appalachensis"
Ronald A. Pursell +
R. H. Zander +
synoicous +  and sexual +
quadrate;oblong +
mitrate +  and cucullate +
cylindric +
inclined +  and erect +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.085 cm0.85 mm <br />8.5e-4 m <br />) +
2-stratose +  and 5-stratose +
hexagonal;oblong +
shrunken +, large +  and enlarged +
ending in mucro +  and percurrent +
distinct +
variable +
reduced +
N.C. +, Pa. +, S.C. +  and Tenn. +
hyaline +, not +  and pigmented +
enlarged +, incrassate +  and small +
quadrate;oblong +
Crevices and surfaces of rocks submerged in swiftly flowing but usually shallow water, sometimes partially emergent +
firm-walled +, 1-stratose +  and irregularly 2-stratose +
1-papillose +  and mammillose +
synoicous +, autoicous +, dioicous +  and sexual +
equal;0mm;4mm +
obtuse-mucronate +  and acute +
unequal +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
serrulate +  and entire +
long-rostrate +  and conic +
0.4 cm4 mm <br />0.004 m <br /> (?) +
axillary +  and basal +
papillose +
reddish +, darkening +  and yellow +
flexuous +  and straight +
elongate +
0.4 cm4 mm <br />0.004 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
branched +  and unbranched +
elongate +
phaneroporous +
Moenkemeyera +  and Octodiceras +
Fissidens appalachensis +
Fissidens +
species +
inclined +  and erect +
ovoid +  and cylindric +
endostomate +  and haplolepidous +
undivided +  and divided +
reduced +
collenchymatous +
often thicker +
brownish;blackish +
0 cm0 mm <br />0 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
abscission +