Hypnum cupressiforme
Hypnum dieckei
cypress-leaf claw-moss, cypress-leaf plaitmoss, hypnum moss
1–8+ cm, pale to yellowish green, brown with age, creeping to erect, complanate-foliate or not, irregularly pinnate to nearly unbranched, attached shoots often regularly pinnate, branches 1–3 cm;
hyalodermis absent, central strand poorly developed;
pseudoparaphyllia filamentous, 1–3-seriate at base.
leaves falcate, curved downward toward substrate, ovate-lanceolate, curving slightly to insertion, tapering to apex, 1–1.5 × 0.4–0.5 mm;
base weakly decurrent;
margins plane, entire to sinuate proximally, often sharply serrate toward apex;
acumen narrow;
costa usually indistinct;
alar cells rectangular, abruptly enlarged, region well defined, 2 or 3 cells high, 3 or 4 cells wide, outermost cells with thinner walls;
basal laminal cells shorter, wider than medial cells, yellowish to brownish, especially adjacent to hyaline alar cells, walls porose;
medial cells 40–60 × 3–4 µm.
strongly imbricate, not to decidedly falcate-secund, ovate to oblong-lanceolate, gradually or abruptly narrowed to apex, 1.5–2 × 0.5–0.8 mm;
base not decurrent, not auriculate;
margins recurved to plane proximally, serrulate (sometimes weakly) distally, occasionally nearly entire;
acumen slender;
costa double and short or obscure;
alar region well defined, basalmost cells larger, sometimes hyaline, yellowish or brownish;
basal laminal cells shorter, wider than medial cells, not pigmented, walls not pitted;
medial cells (50–)60–80 × 3–4(–5) µm.
reddish, 1–2.5(–3) cm.
red-brown when mature, 2–4.5 cm.
dioicous;
inner perichaetial leaves oblong-lanceolate, margins serrulate distally, costa obscure.
dioicous;
inner perichaetial leaves lanceolate, margins toothed, apex finely pointed, costa obscure.
slightly inclined, reddish, cylindric, 1.8–2.5(–2.8) mm;
annulus 1–3-seriate;
operculum conic to rostrate;
endostome cilia 1–2(–3).
nodding when mature, red-brown, cylindric, 3–4.5 mm;
annulus 1- or 2-seriate;
operculum conic;
endostome cilia rudimentary.
Hypnum cupressiforme
Hypnum dieckei
Varieties 9 (4 in the flora).
Hypnum cupressiforme is an extremely polymorphic species, reflected in the more than 60 varieties that have been described. The species has a wide ecological amplitude as well as a nearly cosmopolitan distribution and is found in all climatic regions except the Antarctic. Taxonomic features reliable in most other species of Hypnum are plastic in H. cupressiforme. Within a single clone, it is possible to sort out several named varieties. Variety lacunosum Bridel was noted by H. Ando (1989) to be weakly differentiated in North America, and he tentatively cited specimens from Nova Scotia, Newfoundland, and South Dakota. Ando noted that var. lacunosum typically is robust, thick-complanate to julaceous, with leaves almost straight to weakly falcate and abruptly narrowed to a short acumen, but the North American material is not robust and is therefore problematic.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Hypnum dieckei is distributed around the north Pacific and can be frequent on logs or outcrops near streams. The plants are distinctive especially in summer when sporophytes are produced, because H. dieckei is the only North American species with nodding capsules. The dark stems and pinnate branching associated with excavate alar regions of thin-walled cells set off by inner thick-walled and pigmented basal cells are also usually enough to distinguish H. dieckei. Plants of H. dieckei have branches 0.5–1.5 mm wide. They are often firmly attached by rhizoids, but the rhizoids are usually absent from suberect plants; the alar cells are 40–65 × 20–30 µm and often bulging, with the outer cells somewhat collapsed inward; the supra-alar cells are few and triangular; and the basal laminal cells are rectangular.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Branch leaves 1.5-2 × 0.4-0.6 mm or slightly larger | → 2 |
1. Branch leaves 1-1.4 × 0.2-0.4 mm or slightly smaller | → 3 |
2. Stems weakly complanate-foliate; leaves usually falcate, sometimes strongly so; alar cells not excavate or pigmented. | var. cupressiforme |
2. Stems subjulaceous to complanate-foliate; leaves straight to weakly falcate; alar cells excavate, pigmented. | var. subjulaceum |
3. Leaves usually falcate, sometimes strongly so; margins subentire to distinctly toothed distally. | var. cupressiforme |
3. Leaves straight to somewhat falcate; margins entire or subentire | → 4 |
4. Stems subjulaceous, creeping; leaves oblong-lanceolate, gradually narrowed to apex; laminal cells 60-80 × 3-4 µm (or slightly larger). | var. filiforme |
4. Stems julaceous, creeping to erect; leaves ovate or widely oblong, abruptly narrowed to apex; laminal cells 40-50 × 5-6 µm. | var. julaceum |
WildflowerSearch
iNaturalist
USDA Plants Database
