Fissidens dubius |
Fissidens bryoides |
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fissidens moss |
bryoid fissidens moss, lesser pocket-moss |
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Habit | Plants to 25 × 3.5 mm. | Plants 3–11 × 0.9–3.2 mm. |
Stem | usually branched; axillary hyaline nodules absent; central strand present. |
unbranched and branched; axillary hyaline nodules absent; central strand usually 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, lanceolate to oblong-lanceolate or oblong-lingulate, acute to short-acuminate or obtuse-apiculate, to 0.8–2.7 × 0.2–0.5 mm; dorsal lamina narrowed proximally, ending at or before insertion, infrequently slightly decurrent; vaginant laminae 1/2 leaf length, mostly equal; margin entire but often serrulate distally, limbate on all laminae, limbidium reaching apex or ending a few cells before or partially absent to infrequently completely absent, limbidial cells 1–3-stratose; costa excurrent to ending as many as 6 cells before apex, bryoides-type; laminal cells 1-stratose, distinct, smooth, often slightly bulging, firm-walled, irregularly hexagonal, a few elongate, 6.5–16 µm, somewhat larger in proximal parts of vaginant laminae. |
Seta | to 11 mm. |
1.4–10 mm. |
Sexual condition | dioicous; perigonia on short axillary branches and elongate stems; perichaetia on short axillary branches, mostly near proximal ends of stems. |
polyoicous; naked antheridia and archegonia often in axils of distal leaves. |
Capsule | theca slightly inclined, slightly arcuate, bilaterally symmetric, to 1.8 mm; peristome taxifolius-type; operculum 1–1.4 mm. |
theca exserted, erect, radially symmetric to ± inclined, bilaterally symmetic, 0.2–1.2 mm; peristome bryoides-type; operculum 0.5 mm. |
Calyptra | cucullate, smooth, 1.8 mm. |
cucullate smooth, to 0.5 mm. |
Spores | 13–20 µm. |
10–20 µm. |
Sporophytes | 1 per perchaetium. |
1–2 per perichaetium. |
Fissidens dubius |
Fissidens bryoides |
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Habitat | Soil and humus, bases of trees, decaying wood, rocks and boulders in moist, shaded sites | Soil in moist, shaded sites, stones and rocks (both acidic and basic) in shaded areas, along streams, sometimes inundated, infrequently around bases of trees |
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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AK; AL; AR; AZ; CA; CO; CT; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NH; NJ; NM; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; NB; NF; NS; NT; NU; ON; PE; QC; YT; Mexico; Central America; South America; Europe; Greenland; West Indies; Asia
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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 bryoides is a veritable kaleidoscope of intergrading expressions. At one extreme is F. bryoides in the strict sense, with plants gonioautoicous and the limbidium, 1–3 cells thick, confluent at the leaf apex with the percurrent to short-excurrent costa. At the other extreme is the expression that has been singled out as F. exiguus, with plants rhizautoicous and the 1-stratose limbidium usually restricted to the vaginant laminae of perichaetial leaves. In rare cases the limbidium can be absent from all leaves. All expressions, however, have clear, distinct, 1-stratose, irregularly hexagonal laminal cells, 6.5–16 µm, that in transverse section are no deeper than wide, and that have smooth walls that can be slightly bulging. H. A. Crum and L. E. Anderson (1981) illustrated the major expressions found in the flora area. Axillary, multicellular gemmae have been reported in Indian specimens. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 340. | FNA vol. 27, p. 345. |
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 | F. andersonii, F. bryoides var. incurvus, F. bryoides var. pusillus, F. exiguus, F. exiguus var. falcatulus, F. pusillus, F. synoicous, F. texanus, F. viridulus, F. viridulus var. pusillus, F. viridulus var. tamarindifolius, F. viridulus var. texanus |
Name authority | P. Beauvois: Prodr. Aethéogam., 57. (1805) | Hedwig: Sp. Musc. Frond., 153. (1801) |
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