Fissidens scalaris |
Fissidens crispus |
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Habit | Plants 1.5–6 × 1 mm. | Plants to 10 × 3 mm. |
Stem | unbranched and branched; axillary hyaline nodules present; central strand present. |
unbranched and branched; axillary hyaline nodules absent; central strand present or absent. |
Leaves | as many as 16 pairs, oblong to lanceolate, acute to short-acuminate, to 1.3 × 0.25 mm; dorsal lamina narrowed proximally, ending well above or at insertion; vaginant laminae ± 4/5 leaf length, ± equal, minor lamina ending on or near margin; margin ± entire to crenulate-serrulate, limbate on all laminae, limbidium variable, developed best on vaginant laminae, ceasing well before apex, limbidium cells 1-stratose; costa ending 2–5 cells before apex to percurrent, bryoides-type; laminal cells 1-stratose, distinct, smooth, somewhat bulging, firm-walled, irregularly quadrate to hexagonal, 9–14 µm, increasing somewhat in size and ± oblong in proximal parts of vaginant laminae. |
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. |
Seta | 2–6 mm. |
to 9 mm. |
Sexual condition | rhizautoicous; perigonia gemmiform, proximal to fertile and infertile stems, and as branches along horizontal parts of stems. |
gonioautoicous and rhizautoicous. |
Capsule | theca exserted, erect, radially symmetric, 0.5–1.25 mm; peristome anomalous, variable, even in same theca, teeth undivided, imperfectly divided or divided 4/5 their length, papillose distally, smooth proximally; operculum 0.22–0.3 mm. |
theca exserted, inclined, bilaterally symmetric to erect, radially symmetric, to 1 mm; peristome bryoides-type; operculum 0.5 mm. |
Calyptra | cucullate, smooth, to 0.45 mm. |
cucullate, smooth, 0.8 mm. |
Spores | 20–26 µm. |
10–16 µm. |
Sporophytes | 1 per perichaetium. |
1–2 per perichaetium. |
Fissidens scalaris |
Fissidens crispus |
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Habitat | Bare, disturbed soil of stream banks and roadsides, loess banks, often more or less buried | Moist shaded soil, over rocks near streams, infrequently submerged by fluctuating water levels |
Distribution |
AL; FL; LA; NC; OK; TX; South America |
AZ; CA; CO; LA; MS; NM; NV; OR; TX; UT; WA; AB; BC; Mexico; Central America; South America; West Indies |
Discussion | Fissidens scalaris, although widespread in the southern part of the United States, is infrequently collected. It is best distinguished by its dimorphic stems and undivided to deeply divided, papillose peristome teeth. B. E. Lemmon (1965) published photographs of the development of plants, including perigonial, perichaetial, and infertile stems, and peristome. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 27, p. 347. | FNA vol. 27, p. 349. |
Parent taxa | Fissidentaceae > Fissidens | Fissidentaceae > Fissidens |
Sibling taxa | ||
Synonyms | Moenkemeyera neonii, F. neonii | F. limbatus, F. limbatus var. brevifolius, F. limbatus var. ensiformis, F. pusillus var. brevifolius, F. repandus, F. tortilis |
Name authority | Mitten: J. Linn. Soc., Bot. 12: 596. (1869) | Montagne: Ann. Sci. Nat., Bot., sér. 2, 9: 57. (1838) |
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