Plagiomnium venustum
Plagiomnium carolinianum
magnificent leafy moss, magnificent moss, plagiomnium moss
Carolina plagiomnium moss
green or yellow-green, crisped and contorted, distally often densely twisted around stem when dry, flat when moist, obovate or elliptic, 3–5(–7) mm;
base decurrent or not;
margins toothed to 2/3 leaf length or sometimes just past mid leaf or to base, teeth sharp, of 1–2(–3) cells;
apex acute, acuminate, or rarely obtuse or rounded, cuspidate, cusp toothed;
costa percurrent, excurrent, or rarely subpercurrent;
medial laminal cells short-elongate or ± isodiametric, (17–)25–40(–45) µm, slightly smaller near margins, in longitudinal, rarely diagonal rows, strongly collenchymatous, walls not pitted;
marginal cells linear, in (3–)4–5 rows.
green to dark green, crisped and contorted and somewhat spreading when dry, transversely undulate when moist, oblong-lingulate, oblong, or oblong-elliptic, 5–8(–10) mm;
base long-decurrent;
margins toothed to near base, teeth blunt or sometimes sharp, of 1 (or 2) cells;
apex retuse or emarginate, rarely truncate or rounded, usually short-mucronate;
costa subpercurrent, percurrent, or short-excurrent;
medial laminal cells short-elongate or ± isodiametric, (15–)20–35 µm, somewhat smaller near margins, sometimes in ill-defined rows, collenchymatous, walls pitted;
marginal cells linear, in (2–)3–4 rows.
1–4(–6), yellow, reddish at base, 3–4 cm.
1–4, yellow-green, dark red to blackish with age, 2–4 cm.
synoicous.
synoicous.
horizontal to pendent, oblong, 3–4.5 mm, neck distinct, brown, often wrinkled;
operculum conic-apiculate.
horizontal to pendent, oblong-cylindric, 2.5–3 mm, neck not distinct;
operculum long-rostrate.
34–40 µm.
30–35 µm.
stems 2–4(–6) cm, not dendroid;
sterile stems absent.
stems 2–3(–5) cm, not dendroid;
sterile stems to 5(–20) cm.
Plagiomnium venustum
Plagiomnium carolinianum
Plagiomnium venustum is the only species of the genus that lacks sterile stems. It is a common western species that forms large, handsome mats or turfs in many northwest coastal forests, especially noticeable on tree bases. Sporophytes are common. Another distinctive feature of P. venustum is the presence of dark and mammillose stomatal guard cells in the necks of the capsules.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Plagiomnium carolinianum and P. undulatum, an apparent introduction in British Columbia, are differentiated from other species of Plagiomnium by their long, usually oblong-lingulate or lingulate leaves, which are transversely undulate when moist, and the relatively small size of the laminal cells. Plagiomnium undulatum, to date known only from south-coastal British Columbia, is a much larger plant than P. carolinianum with longer leaves, and its erect stems often branch distally, forming irregular, palm treelike heads. While other species of Plagiomnium have straight capsules, the capsules of P. carolinianum are slightly curved when dry.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
BC
CalFlora
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
