Fissidens dubius |
Fissidens aphelotaxifolius |
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fissidens moss |
fissidens moss |
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Habit | Plants to 25 × 3.5 mm. | Plants to 17 × 2–3 mm. |
Stem | usually branched; axillary hyaline nodules absent; central strand present. |
branched; axillary hyaline nodules absent; central strand present. |
Leaves | as many as 25 pairs, often undulate, oblong to lanceolate, obtuse to acute, often apiculate, to 3.5 × 0.7 mm; dorsal lamina truncate-rounded proximally, ending at insertion, not decurrent; vaginant laminae 2/3 the leaf length, ± unequal, minor lamina ending near margin; margin crenulate to crenulate-serrulate but unevenly serrate at leaf apex, elimbate; costa ending a few cells before apex to percurrent, taxifolius-type; laminal cells irregularly 2-stratose in dorsal and ventral laminae, ± obscure, smooth, bulging, firm-walled, rounded-hexagonal, 7–10 µm, 3–4 rows of marginal cells thinner, walls slightly thicker, forming a pale marginal band. |
as many as 20 pairs, lorate to lanceolate, acute to rounded, apiculate, to 2.35 × 0.35–0.65 mm; dorsal lamina usually rounded proximally, ending at insertion, sometimes ending before insertion or slightly decurrent; vaginant laminae 1/2 leaf length, ± equal, minor lamina ending on or near margin; margin mostly crenulate on dorsal and ventral laminae, mostly serrulate on vaginant laminae and distally, elimbate; costa variable in length, even on same plant, excurrent into apiculus to ending several cells before apex, taxifolius-type; lamina cells 1-stratose, distinct, smooth, slightly bulging, firm-walled, quadrate to irregularly hexagonal, 6–15 µm, somewhat larger justacostally, marginal row thinner, paler. |
Seta | to 11 mm. |
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Sexual condition | dioicous; perigonia on short axillary branches and elongate stems; perichaetia on short axillary branches, mostly near proximal ends of stems. |
dioicous(?); perigonia unknown; perichaetia on short proximal stems and axillary in proximal leaves. |
Capsule | theca slightly inclined, slightly arcuate, bilaterally symmetric, to 1.8 mm; peristome taxifolius-type; operculum 1–1.4 mm. |
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Calyptra | cucullate, smooth, 1.8 mm. |
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Spores | 13–20 µm. |
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Sporophytes | 1 per perchaetium. |
, calyptra, and spores not known. |
Fissidens dubius |
Fissidens aphelotaxifolius |
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Habitat | Soil and humus, bases of trees, decaying wood, rocks and boulders in moist, shaded sites | Wet soil, humus, and rocks along streams, near waterfalls, in damp or wet crevices of cliffs |
Distribution |
AK; AL; AR; AZ; CA; CT; DE; FL; GA; IA; IL; IN; KS; KY; MA; ME; MI; MN; MO; MS; NC; NE; NH; NY; OK; PA; SC; TN; TX; VA; VT; WI; WV; NB; NF; NS; ON; QC; Mexico; Central America; West Indies; Europe; Asia; Pacific Islands
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CA; OR; WA; BC |
Discussion | In contrast to Fissidens adianthoides, F. dubius has smaller, irregularly 2-stratose, obscure laminal cells. Subterranean, irregularly globose, multicellular rhizoidal gemmae have been reported for F. dubius as well as F. osmundioides and F. taxifolius in Europe and Japan. Z. Iwatsuki and T. Suzuki (1982) cited the occurrence of dwarf male plants (small perigonial stems located on the leaves of perichaetial plants) in Japanese specimens. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Fissidens aphelotaxifolius can be confused with F. taxifolius but is best distinguished by its smooth and slightly bulging laminal cells, distinct from the conspicuously mammillose cells in the ventral laminae of the F. taxifolius. Moreover, the plants tend to be smaller and leaf apex more coarsely serrulate than in F. taxifolius. Vegetative propagation of F. aphelotaxifolius is apparently by abundant branched, chlorophyllose filaments. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 340. | FNA vol. 27, p. 342. |
Parent taxa | Fissidentaceae > Fissidens | Fissidentaceae > Fissidens |
Sibling taxa | ||
Synonyms | F. adianthoides var. semicristatus, F. cristatus, F. cristatus var. winonensis, F. decipiens var. winonensis, F. floridanus | |
Name authority | P. Beauvois: Prodr. Aethéogam., 57. (1805) | Pursell: Bull. Torrey Bot. Club 103: 35, figs. 1–15. (1976) |
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