Fissidens crispus |
Fissidens dubius |
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fissidens moss |
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Habit | Plants to 10 × 3 mm. | Plants to 25 × 3.5 mm. |
Stem | unbranched and branched; axillary hyaline nodules absent; central strand present or absent. |
usually branched; axillary hyaline nodules absent; central strand present. |
Leaves | as many as 20 pairs, elliptic to broadly lanceolate to oblong-lingulate, acute, short-acuminate to obtuse-apiculate, to 2 × 0.5 mm; dorsal lamina narrowed proximally, ending before insertion to ± decurrent; vaginant laminae 2/3–3/4 leaf length, equal; margin ± entire but usually serrulate distally, limbate on all laminae, limbidium usually ending a few cells before apex, frequently edged by 1–2 rows of quadrate to oblong chlorophyllose cells in proximal parts of vaginant laminae, limbidial cells 1–2-stratose; costa percurrent to ending 2–5 cells before leaf, infrequently short-excurrent, bryoides-type; laminal cells 1-stratose, smooth, strongly bulging, densely chlorophyllose, ± obscure, firm-walled, irregularly quadrate to hexagonal, usually arranged in discernable rows in distal part of leaf, 6–10 µm, twice as deep as wide. |
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. |
Seta | to 9 mm. |
to 11 mm. |
Sexual condition | gonioautoicous and rhizautoicous. |
dioicous; perigonia on short axillary branches and elongate stems; perichaetia on short axillary branches, mostly near proximal ends of stems. |
Capsule | theca exserted, inclined, bilaterally symmetric to erect, radially symmetric, to 1 mm; peristome bryoides-type; operculum 0.5 mm. |
theca slightly inclined, slightly arcuate, bilaterally symmetric, to 1.8 mm; peristome taxifolius-type; operculum 1–1.4 mm. |
Calyptra | cucullate, smooth, 0.8 mm. |
cucullate, smooth, 1.8 mm. |
Spores | 10–16 µm. |
13–20 µm. |
Sporophytes | 1–2 per perichaetium. |
1 per perchaetium. |
Fissidens crispus |
Fissidens dubius |
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Habitat | Moist shaded soil, over rocks near streams, infrequently submerged by fluctuating water levels | Soil and humus, bases of trees, decaying wood, rocks and boulders in moist, shaded sites |
Distribution |
AZ; CA; CO; LA; MS; NM; NV; OR; TX; UT; WA; AB; BC; Mexico; Central America; South America; West Indies |
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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Discussion | Three species belong to the Fissidens crispus complex; F. crispus, F. minutulus, and F. sublimbatus. A well-developed limbidium and small (6–10 µm), bulging, obscure laminal cells that in transverse section are twice as deep as wide characterize all three. Fissidens crispus, better known in western North America as F. limbatus, is highly variable and widespread, ranging widely in tropical America, where it also attains its greatest variability. It is best distinguished by laminal cells that are usually arranged in discernable rows in the distal parts of leaves. The dorsal lamina is quite variable, ending above the insertion to long-decurrent as in some tropical expressions. Leaves, when dry, are usually crispate. The limbidium is found on all or most leaves and usually extends to or ends just before the apex. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 27, p. 349. | FNA vol. 27, p. 340. |
Parent taxa | Fissidentaceae > Fissidens | Fissidentaceae > Fissidens |
Sibling taxa | ||
Synonyms | F. limbatus, F. limbatus var. brevifolius, F. limbatus var. ensiformis, F. pusillus var. brevifolius, F. repandus, F. tortilis | F. adianthoides var. semicristatus, F. cristatus, F. cristatus var. winonensis, F. decipiens var. winonensis, F. floridanus |
Name authority | Montagne: Ann. Sci. Nat., Bot., sér. 2, 9: 57. (1838) | P. Beauvois: Prodr. Aethéogam., 57. (1805) |
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