Key to the Moss Genera of North America North of Mexico
Treatment appears in FNA Volume 28.
Revision as of 21:09, 8 August 2018 by imported>Admin
This key to the genera of North American mosses is intended to complement not replace the keys to genera included with each family treatment in the Flora. It is a somewhat modified version of a key written earlier (D. H. Vitt and W. R. Buck 1992) to honor Howard A. Crum on his retirement from the University of Michigan.
Contents
Keys
Primary Key
1 | Gametophytes seemingly absent (consisting only of protonemata); capsules asymmetric; setae papillose. | Buxbaumia |
1 | Gametophytes present (with obvious leaves); capsules and setae various. | > 2 |
2 | Laminal cells arranged in a network of narrow, green cells alternating with large hyaline cells; branches usually in clusters. | Sphagnum |
2 | Laminal cells of one kind (green), or if two kinds, branches never in clusters. | > 3 |
3 | Leaves attached in 2 rows on opposite sides of stem (distichous). | > 4 |
4 | Leaves appearing split at base, consisting of 2 vaginant laminae clasping stem and base of leaf above (equitant). | Fissidens |
4 | Leaves with expanded bases, not clasping leaf above. | > 5 |
5 | Leaves ecostate; protonemata luminous. | Schistostega |
5 | Leaves with single costa; protonemata not luminous. | > 6 |
6 | Vegetative leaves with smooth mucro; perichaetial leaves with smooth subula. | Bryoxiphium |
6 | All leaves with papillose, linear subula. | Distichium |
3 | Leaves attached all around stem (foliate stems sometimes flattened [complanate]). | > 7 |
7 | Leaves without lamellae or filaments on adaxial costal surface (but propagula sometimes present). | > 8 |
8 | Leaves deeply lobed, lobes linear-terete. | Takakia |
8 | Leaves never lobed, flattened (sometimes concave with margins inrolled or recurved). | > 9 |
9 | Leaves ecostate, costa short and double, double or single to 1/3 leaf length, or single with 2 or 3 lateral spurs. | Subkey A |
9 | Leaves with single costa to at least mid leaf. | Subkey B |
7 | Leaves with lamellae or filaments on adaxial costal surface (excluding propagula). | > 10 |
10 | Leaves with filaments on adaxial costal surface. | > 11 |
11 | Leaf margins reflexed to revolute. | Crossidium |
11 | Leaf margins broadly inrolled (mostly obscuring filaments). | Aloina |
10 | Leaves with lamellae on adaxial costal surface. | > 12 |
12 | Leaves bordered with elongate marginal cells. | Atrichum |
12 | Leaves without elongate marginal cells. | > 13 |
13 | Leaves ciliate at distal part of hyaline sheath. | Bartramiopsis |
13 | Leaves eciliate. | > 14 |
14 | Distal leaf margins 2-stratose with paired, multicellular teeth; leaf apices with slender, smooth, caducous awns. | Lyellia |
14 | Distal leaf margins 1-stratose with single teeth or entire; leaf apices muticous or with serrate awns. | > 15 |
15 | Lamellae 2 – 4; leaves hyaline awned; plants small, less than 5 mm; peristome absent or rudimentary and fragile. | Pterygoneurum |
15 | Lamellae 4 – 50; leaves mostly not awned; plants mostly larger; peristome of 32 or 64 persistent teeth. | > 16 |
16 | Lamellae distinctly wavy. | > 17 |
17 | Distal leaf margins not bordered. | Oligotrichum |
17 | Distal leaf margins with border of hyaline, short-rhombic cells. | Psilopilum |
16 | Lamellae straight. | > 18 |
18 | Calyptrae naked or with few hairs. | > 19 |
19 | Distal abaxial leaf lamellae and teeth absent. | Meiotrichum |
19 | Distal abaxial leaf lamellae and/or teeth present. | Oligotrichum |
18 | Calyptrae densely hairy. | > 20 |
20 | Capsules present. | > 21 |
21 | Capsules sharply 4-angled. | Polytrichum |
21 | Capsules cylindric or bluntly 2 – 4-angled. | > 22 |
22 | Capsules with stomata; lumina of apical cells of lamellae pyriform. | Polytrichastrum |
22 | Capsules without stomata; lumina of apical cells of lamellae not pyriform. | Pogonatum |
20 | Capsules absent. | > 23 |
23 | Apical cells of lamellae papillose. | > 24 |
24 | Apical cells elliptic-pyriform. | Polytrichastrum |
24 | Apical cells rounded, quadrate or oblate. | Pogonatum |
23 | Apical cells of lamellae smooth or with faint cuticular ridges. | > 25 |
25 | Plants larger; leaves with or without awns. | Polytrichum |
25 | Plants small, less than 6 mm; leaves never awned. | Pogonatum |
Subkey A
1 | Leaves appearing ecostate, but with costae single and occupying entire leaf area, thus lamina appearing multistratose. | > 2 |
2 | Leaves lanceolate; green cells 4-sided in transverse section. | Leucobryum |
2 | Leaves ligulate; green cells 3-sided in transverse section. | Octoblepharum |
1 | Leaves ecostate, costae very short and single, or double; lamina always 1-stratose. | > 3 |
3 | Distal laminal cells papillose or prorulose. | > 4 |
4 | Leaf apices hyaline. | > 5 |
5 | Laminal cell papillae 1 or 2, forked; capsules immersed, smooth; perichaetial leaf margins ciliate; widespread. | Hedwigia |
5 | Laminal cell papillae 1, simple; capsules exserted, ribbed; perichaetial leaf margins entire; restricted to w North America. | Pseudobraunia |
4 | Leaf apices concolorous. | > 6 |
6 | Laminal cells multipapillose. | > 7 |
7 | Papillae arranged in rows over lumina; laminal cells more than 5:1. | Taxithelium |
7 | Papillae randomly arranged over lumina; laminal cells less than 4:1. | > 8 |
8 | Leaf apices obtuse; stems complanate-foliate. | Erpodium, 27 – 2. Solmsiella |
8 | Leaf apices short-acuminate; stems symmetrically foliate. | Braunia |
6 | Laminal cells 1-papillose or prorulose. | > 9 |
9 | Stems 2-or 3-pinnate, forming ascending series of flat, frondose tiers. | Hylocomium |
9 | Stems simple or 1-pinnate, not forming ascending series of fronds. | > 10 |
10 | Leaves plicate. | > 11 |
11 | Costae extending beyond mid leaf; leaves spreading to squarrose. | Rhytidiadelphus |
11 | Costae short; leaves falcate-secund. | Ctenidium |
10 | Leaves not plicate. | > 12 |
12 | Plants reddish black, tightly attached to rock. | Andreaea |
12 | Plants green, on various substrates. | > 13 |
13 | Plants minute, less than 2 mm, acrocarpous. | Ephemerum |
13 | Plants large, more than 1 cm, pleurocarpous. | > 14 |
14 | Costae extending to near leaf apex. | Callicostella |
14 | Costae ending below mid leaf. | > 15 |
15 | Alar cells many, oblate to rounded, extending up margins; restricted to Pacific Northwest. | Nogopterium |
15 | Alar cells few, mostly quadrate, scarcely extending up margins; widespread. | > 16 |
16 | Medial laminal cells less than 5:1. | > 17 |
17 | Stem and branch leaves differentiated. | Heterocladium |
17 | Stem and branch leaves similar. | > 18 |
18 | Leaves broadly ovate, strongly concave; apices obtuse to obtuse-apiculate. | Myurella |
18 | Leaves lanceolate to ovate-lanceolate, weakly concave or flat; apices acute to acuminate. | > 19 |
19 | Leaf apices acute; margins serrulate only distally; propagula often present in leaf axils; n North America. | Pterigynandrum |
19 | Leaf apices acuminate; margins serrulate throughout; propagula absent; e United States. | Schwetschkeopsis |
16 | Medial laminal cells more than 5:1. | > 20 |
20 | Basal row of laminal cells with large prorula at proximal end. | Dacryophyllum |
20 | Basal row of laminal cells smooth. | > 21 |
21 | Apical laminal cells much shorter than medial cells. | Taxiphyllum |
21 | Apical laminal cells scarcely differentiated. | > 22 |
22 | Leaf apices acute; laminal cells prorulose only at distal ends. | Leptohymenium |
22 | Leaf apices slenderly acuminate; laminal cells prorulose at both ends. | Chryso-hypnum |
3 | Distal laminal cells smooth (rarely with minute cuticular roughenings). | > 23 |
23 | Leaf apices with hyaline awn. | > 24 |
24 | Laminal cells 2:1 or less, oblate-hexagonal throughout; peristome absent. | Erpodium |
24 | Laminal cells more than 3:1, basal cells quadrate, distal cells short-rhomboidal; peristome present. | Venturiella |
23 | Leaf apices concolorous. | > 25 |
25 | Plants aquatic, submerged at least part of year; leaves keeled or flat. | Fontinalis |
25 | Plants sometimes in wet habitats but never submerged; leaves never keeled. | > 26 |
26 | Plants acrocarpous, usually less than 4 cm. | > 27 |
27 | Plants on rock. | > 28 |
28 | Plants reddish black; capsules valvate. | Andreaea |
28 | Plants greenish brown; capsules with 4 peristome teeth. | Tetrodontium |
27 | Plants on bare soil. | > 29 |
29 | Protonemata few; capsules globose; calyptrae very small, persistent. | Micromitrium |
29 | Protonemata many; capsules ovoid, apiculate; calyptrae campanulate-mitrate, deciduous. | Ephemerum |
26 | Plants pleurocarpous, mostly larger. | > 30 |
30 | Costae single, with 2 or more shorter, supplementary costae at base. | Antitrichia |
30 | Costae double, or if single very short and without supplementary costae. | > 31 |
31 | Costae double, extending to or beyond mid leaf. | > 32 |
32 | Stem paraphyllia many. | > 33 |
33 | Stem leaves plicate; bases decurrent. | Hylocomiastrum |
33 | Stem leaves not plicate; bases not decurrent. | Loeskeobryum |
32 | Stem paraphyllia absent. | > 34 |
34 | Laminal cells thin-walled, lax, abruptly bordered by elongate cells. | Cyclodictyon |
34 | Laminal cells firm-walled, not or only gradually bordered. | > 35 |
35 | Plants in mats; leaves falcate-secund at least at branch apices; exostome teeth striate, furrowed. | Trachyxiphium |
35 | Plants tufted; leaves somewhat contorted when dry but not falcate; exostome teeth papillose, not furrowed[Lepidopilum, see 49. Hookeriaceae, v. 28, p. 248] | > 31 |
31 | Costae single or double, usually ending just beyond leaf base. | > 36 |
36 | Leaf apices obtuse; plants small, rare, restricted to mountains of se United States. | > 37 |
37 | Leaves symmetric, without basal lobe. | Bryocrumia |
37 | Leaves asymmetric, with basal lobe. | Homaliadelphus |
36 | Leaf apices acute to acuminate, at least apiculate; plants mostly larger, widespread. | > 38 |
38 | Laminal cells lax, hexagonal. | > 39 |
39 | Lateral and dorsal leaves with similar areolation; stems irregularly branched. | Hookeria |
39 | Lateral and dorsal leaves differentiated in areolation; stems pinnate. | Vesicularia |
38 | Laminal cells firm-to thick-walled, rounded to linear. | > 40 |
40 | Leaf bases slenderly long-decurrent. | > 41 |
41 | Plants small to medium-sized, green; leaves not undulate; laminal cells smooth. | Plagiothecium |
41 | Plants large, whitish; leaves strongly undulate; laminal cells with minute, granular, cuticular papillae. | Buckiella |
40 | Leaf bases not at all decurrent to broadly auriculate. | > 42 |
42 | Leaves dimorphic, abaxial ones symmetric, cultriform; with large area of enlarged alar cells on one side of costa. | Pilosium |
42 | Leaves monomorphic, symmetric; alar cells various. | > 43 |
43 | Plants slender, threadlike or in thin mats; leaves mostly less than 1 mm. | > 44 |
44 | Alar cells in 1 basal row, somewhat inflated, rounded. | Hageniella |
44 | Alar cells few, quadrate. | > 45 |
45 | Branch leaves more than 0.5 mm. | Homomallium |
45 | Branch leaves less than 0.5 mm. | > 46 |
46 | Ecostate or costae very short and double; laminal cells rhombic. | Platydictya |
46 | Costae short and single; laminal cells rounded-elliptic. | Pseudoleskeella |
43 | Plants larger; leaves more than 1 mm. | > 47 |
47 | Leaves falcate-secund. | > 48 |
48 | Distal laminal cells oblong-rhombic, ca. 3:1. | > 49 |
49 | Alar cells few, oblong-quadrate, in 1 or 2 rows along insertion. | Sematophyllum |
49 | Alar cells many, oblate, in many rows extending up margins. | Leucodon |
48 | Distal laminal cells ± linear, more than 6:1. | > 50 |
50 | Stems regularly and closely pinnate, featherlike, fronds flat, erect to ascending. | Ptilium |
50 | Stems irregularly pinnate to unbranched, not featherlike, prostrate to loosely ascending. | > 51 |
51 | Mature branches erect, producing many conspicuous propagula in distal leaf axils. | Platygyrium |
51 | Branches not producing propagula in leaf axils. | > 52 |
52 | Branches curved-secund when dry, erect when moist; alar cells small, quadrate. | Pylaisia |
52 | Branches little altered when dry; alar cells various. | > 53 |
53 | Alar cells when differentiated quadrate, sometimes enlarged but not inflated. | > 54 |
54 | Stem paraphyllia present. | Rhytidiopsis |
54 | Stem paraphyllia absent. | > 55 |
55 | Plants very large (stem leaves 3.5 – 5 mm); stems ascending to erect; leaves plicate. | Rhytidiadelphus |
55 | Plants smaller (stem leaves less than 3.5 mm); stems prostrate to ascending; leaf plication various. | > 56 |
56 | Alar cells absent or very few; pale propagula often clustered in leaf axils. | Isopterygiopsis |
56 | Alar cells distinctly differentiated; propagula absent, or if present, not clustered in leaf axils. | > 57 |
57 | Plants on wet rock in mountain streams. | Hygrohypnum |
57 | Plants in various habitats but not as above. | > 58 |
58 | Costae to 1/3 leaf length with branches not meeting at base; Alaska, Yukon. | Gollania |
58 | Costae mostly shorter, branches meeting at base; widespread. | Hypnum |
53 | Alar cells quadrate to oblong, inflated. | > 59 |
59 | Plants in calcareous fens or marl pools, dark reddish brown; leaf apices obtuse. | Scorpidium |
59 | Plants in other habitats, golden to green; leaf apices acute to acuminate. | > 60 |
60 | Plants on wet rock in mountain streams. | Hygrohypnum |
60 | Plants in various habitats but not as above. | > 61 |
61 | Alar cells inflated in several rows, walls thick; leaf margins strongly serrate. | Heterophyllium |
61 | Alar cells inflated in 1 (or 2) rows, or if more, walls thin; leaf margins entire to serrulate. | > 62 |
62 | Stems surrounded by enlarged, thin-walled, hyaline cortical cells (hyalodermis); alar regions large, subdecurrent. | Hypnum |
62 | Stems surrounded by small, thick-walled, concolorous cells; alar regions in 1 (or 2) rows. | > 63 |
63 | Plants very shiny; leaves 0.8 – 1.4 mm; distal margins densely serrulate; capsules inclined, asymmetric. | Brotherella |
63 | Plants slightly shiny; leaves 0.5 – 1.1 mm; distal margins distantly serrulate; capsules erect, symmetric. | Pylaisiadelpha |
47 | Leaves straight. | > 64 |
64 | Stem leaf apices abruptly contracted to long setaceous point. | > 65 |
65 | Leaf apices hyaline; alar cells scarcely differentiated. | Iwatsukiella |
65 | Leaf apices yellow; alar cells inflated, hyaline. | Wijkia |
64 | Stem leaf apices acute, acuminate or apiculate. | > 66 |
66 | Leaves squarrose-recurved when dry; apices channeled. | > 67 |
67 | Stem leaves greater than 2.5 mm; alar cells oblong, somewhat inflated, intramarginal. | Rhytidiadelphus |
67 | Stem leaves less than 2.5 mm; alar cells oblong to subquadrate, inflated or not, marginal. | > 68 |
68 | Leaves greater than 1.6 mm. | Campylium |
68 | Leaves less than 1.7 mm. | Campylophyllum |
66 | Leaves erect to spreading, or if squarrose only when moist; apices mostly not channeled. | > 69 |
69 | Plants on wet rock in mountain streams; leaves ovate, concave. | Hygrohypnum |
69 | Plants in various habitats but not as above; leaves various. | > 70 |
70 | Stems complanate-foliate. | > 71 |
71 | Alar cells many, quadrate; capsules erect. | Entodon |
71 | Alar cells few, variously shaped; capsules usually inclined. | > 72 |
72 | Plants on vertical substrates, tree trunks or rock. | Neckera |
72 | Plants on horizontal substrates, rarely on extreme base of trees. | > 73 |
73 | Leaf margins serrulate throughout. | > 74 |
74 | Apical laminal cells undifferentiated. | Herzogiella |
74 | Apical laminal cells shorter than medial cells. | Taxiphyllum |
73 | Leaf margins entire or serrulate only distally. | > 75 |
75 | Rhizoids arising from leaf axils, papillose; leaf margins ± entire. | Isopterygiopsis |
75 | Rhizoids arising from below leaf insertion, smooth; leaf margins serrulate distally. | > 76 |
76 | Pseudoparaphyllia filamentous; annuli not differentiated; sexual condition mostly monoicous. | Isopterygium |
76 | Pseudoparaphyllia absent; annuli differentiated; sexual condition mostly dioicous. | Pseudotaxiphyllum |
70 | Stems symmetrically foliate. | > 77 |
77 | Alar cells inflated. | > 78 |
78 | Stems erect, hyalodermis present; alar cells hyaline, in auricles. | Calliergonella |
78 | Stems prostrate, hyalodermis absent; alar cells yellowish, not in auricles. | > 79 |
79 | Alar cells uniform, without enlarged basal row; stem apices flattened. | Callicladium |
79 | Alar cells with enlarged basal row; stem apices not flattened. | > 80 |
80 | Alar regions rounded to insertion; exostome teeth furrowed. | Acroporium |
80 | Alar regions not rounded to insertion; exostome teeth not furrowed. | > 81 |
81 | Exostome teeth striate; endostome with evident basal membrane and segments; e North America. | Sematophyllum |
81 | Exostome teeth smooth or faintly papillose; endostome fugacious, appearing absent; restricted to c Florida in oak scrub. | Donnellia |
77 | Alar cells rectangular to quadrate, not inflated. | > 82 |
82 | Alar cells many (more than 50), quadrate, regions extending up margins in 12+ rows. | > 83 |
83 | Stem paraphyllia many. | Alsia |
83 | Stem paraphyllia absent. | > 84 |
84 | Leaves less than 0.8 mm; laminal cells wit h obscure cuticular roughenings. | Leptopterigynandrum |
84 | Leaves more than 1 mm; laminal cells smooth. | > 85 |
85 | Alar cells extending up margins more than 1/3 leaf length. | > 86 |
86 | Secondary stems simple or with few branches. | Leucodon |
86 | Secondary stems freely subpinnate. | Forsstroemia |
85 | Alar cells extending up margins less than 1/6 leaf length. | > 87 |
87 | Leaf apices mostly obtuse to acute, rarely acuminate; bases never decurrent; endostome cilia absent; widespread but not in coastal w North America. | Entodon |
87 | Leaf apices acuminate; bases somewhat decurrent; endostome cilia present; restricted to coastal w North America, California to British Columbia. | Tripterocladium |
82 | Alar cells fewer (less than 25), quadrate to rectangular, regions extending up margins in less than 8 rows. | > 88 |
88 | Plants epiphytic; primary stems creeping, secondary stems erect. | > 89 |
89 | Secondary stems unbranched; leaves spreading with squarrose apices; propagula common. | Jaegerina |
89 | Secondary stems irregularly branched; leaves erect; propagula absent. | Neomacounia |
88 | Plants terrestrial or rarely on base of trees; primary and secondary stems not differentiated. | > 90 |
90 | Stem hyalodermis present; leaf margins serrulate to base. | Herzogiella |
90 | Stem hyalodermis absent; leaf margins entire or serrulate distally. | > 91 |
91 | Leaves plicate. | Orthothecium |
91 | Leaves not plicate. | > 92 |
92 | Leaf apices obtuse-apiculate. | > 93 |
93 | Plants in fens; stems green, sparsely branched. | Pseudocalliergon |
93 | Plants widespread in acidic habitats of boreal forests; stems reddish orange, pinnate. | Pleurozium |
92 | Leaf apices acuminate. | > 94 |
94 | Laminal cells not porose except at insertion; pseudoparaphyllia filamentous; coastal e North America inland to Midwest. | Isopterygium |
94 | Laminal cells porose throughout; pseudoparaphyllia absent or foliose; boreal, arctic, and alpine habitats. | Orthothecium |
Subkey B
1 | Stems erect, dendroid or frondose from stipe. | > 2 |
2 | Leaves bordered by elongate cells. | > 3 |
3 | Branch leaves dimorphic. | Hypopterygium |
3 | Branch leaves monomorphic. | > 4 |
4 | Stems ± evenly branched, resembling small palm trees; stem leaves highly modified, triangular, hyaline or with hyaline apices; distal leaves ovate-triangular, flat. | Leucolepis |
4 | Stems irregularly branched; proximal stem leaves similar to distal leaves, lingulate, undulate. | Plagiomnium |
2 | Leaves not bordered. | > 5 |
5 | Stem paraphyllia absent. | > 6 |
6 | Branch leaf apical laminal cells long-hexagonal; costae slender, tapering toward apex. | Porotrichum |
6 | Branch leaf apical laminal cells rhombic; costae s trong, not tapering toward apex. | Thamnobryum |
5 | Stem paraphyllia or filamentous, paraphyllialike structures present. | > 7 |
7 | Plants epiphytic; stems pinnate, frondose, curled when dry, spreading when moist. | Dendroalsia |
7 | Plants terrestrial (rarely on tree bases); stems dendroid, little altered when dry. | > 8 |
8 | Branch leaf bases cordate to auriculate, auricles not inflated; stem paraphyllia present; stem leaf margins serrate. | Climacium |
8 | Branch leaf bases long-decurrent, decurrencies of inflated, hyaline cells; stem lamellae present; stem leaf margins entire. | Pleuroziopsis |
1 | Stems prostrate to erect, simple to pinnate. | > 9 |
9 | Plants blackish, tightly attached to rock in arctic and montane areas; capsules valvate. | > 10 |
10 | Plants on acidic rock; capsules hygroscopic, elliptic when moist, tapering to point. | Andreaea |
10 | Plants on calcareous rock; capsules not hygroscopic, turbinate, obtuse-conic. | Andreaeobryum |
9 | Plants greenish to blackish, on various substrates; capsules cleistocarpous or operculate, never valvate. | > 11 |
11 | Leaves strongly squarrose-recurved; in fens. | Paludella |
11 | Leaves erect to squarrose; in various habitats. | > 12 |
12 | Stem paraphyllia present. | > 13 |
13 | Stems complanate-foliate; stem leaves undulate. | Neckera |
13 | Stems symmetrically foliate; stem leaves not undulate. | > 14 |
14 | Alar regions well differentiated, cells inflated. | > 15 |
15 | Stem leaves not plicate; paraphyllia foliose, few to many. | Cratoneuron |
15 | Stem leaves deeply plicate; paraphyllia filamentous, many. | Palustriella |
14 | Alar regions mostly not differentiated, if so, cells not inflated. | > 16 |
16 | Paraphyllia with cells elongate, more than 5:1, at least at apex. | > 17 |
17 | Leaf margins entire to serrulate. | Elodium |
17 | Leaf margins strongly serrate distally. | > 18 |
18 | Medial laminal cells short, oblong to quadrate, with 1 massive central papilla. | Echinophyllum |
18 | Medial laminal cells elongate or shortly oblong, smooth. | > 19 |
19 | Distal laminal cells linear, more than 8:1; widespread | Hylocomiastrum |
19 | Distal laminal cells short, 2 – 5:1; se United States. | Climacium |
16 | Paraphyllia with cells short, 1 – 3:1. | > 20 |
20 | Paraphyllia with cells papillose. | > 21 |
21 | Laminal cells 1-papillose. | > 22 |
22 | Stems 1-pinnate; laminal cells papillose on both surfaces. | Abietinella |
22 | Stems 2-or 3-pinnate; laminal cells papillose only abaxially. | Thuidium |
21 | Laminal cells multipapillose. | > 23 |
23 | Plants large; sexual condition dioicous; laminal cells papillose only abaxially. | Thuidium |
23 | Plants small; sexual condition autoicous; laminal cells papillose on both surfaces. | > 24 |
24 | Stems 1-or 2-pinnate; leaves incurved when dry; laminal cells flat; setae smooth or papillose. | Cyrto-hypnum |
24 | Stems 1-pinnate; leaves not incurved when dry; laminal cells strongly bulging; setae smooth. | Rauiella |
20 | Paraphyllia with cells smooth. | > 25 |
25 | Laminal cell papillae large, forked or elongate and curved; leaves broadly ovate. | Thelia |
25 | Laminal cell papillae short, simple; leaves lanceolate to ovate-lanceolate. | > 26 |
26 | Costae pellucid; leaf hair-points usually present. | Claopodium |
26 | Costae opaque; leaf hair-points absent. | > 27 |
27 | Stem and branch leaves differentiated. | Haplocladium |
27 | Stem and branch leaves similar. | > 28 |
28 | Laminal cells elongate, oblong-rhombic to oblong-linear. | > 29 |
29 | Capsules erect, symmetric; endostome segments narrow, not keeled. | Lescuraea |
29 | Capsules inclined, asymmetric; endostome segments broader, keeled. | Pseudoleskea |
28 | Laminal cells isodiametric or nearly so, hexagonal to short-rhombic. | > 30 |
30 | Capsules erect, symmetric; exostome teeth papillose; mostly e North America. | Leskea |
30 | Capsules inclined, asymmetric; exostome teeth striate; mostly w North America. | Pseudoleskea |
12 | Stem paraphyllia absent. | > 31 |
31 | Plants whitish; leaves composed mostly of costa, multistratose, with small green cells enclosed between 2 layers of hyaline cells on both surfaces. | > 32 |
32 | Green cells in transverse section 4-sided; terrestrial. | Leucobryum |
32 | Green cells in transverse section 3-sided; occasionally terrestrial. | Octoblepharum |
31 | Plants greenish to blackish, rarely whitish; leaves usually with conspicuous lamina, if not, green and hyaline cells of ca. equal size, with 1 layer of hyaline cells on either side of green cells. | > 33 |
33 | Leaf margins strongly incurved to involute, at least when dry. | > 34 |
34 | Leaf margins incurved when dry or moist. | > 35 |
35 | Laminal cells smooth; costal stereid band 1. | Indusiella |
35 | Laminal cells papillose; costal stereid bands 2. | Weissia |
34 | Leaf margins incurved when dry, plane when moist. | > 36 |
36 | Costal stereid band 1; peristome present. | Plaubelia |
36 | Costal stereid bands 2; peristome absent. | Hyophila |
33 | Leaf margins plane to recurved. | > 37 |
37 | Plants minute, on soil (or rarely rock), ephemeral, often with persistent protonemata; capsules immersed. | > 38 |
38 | Capsules operculate. | > 39 |
39 | Exothecial cells collenchymatous. | Aphanorrhegma |
39 | Exothecial cells not collenchymatous. | Physcomitrium |
38 | Capsules cleistocarpous. | > 40 |
40 | Spores few per capsule, more than 100 µm. | > 41 |
41 | Leaves broadly ovate or elliptic; apices abruptly narrowed to awn; plants with slender, subterranean rhizomes. | Lorentziella |
41 | Leaves oblong to lanceolate; apices acute to subulate; plants not rhizomatous. | Archidium |
40 | Spores many per capsule, less than 60 µm. | > 42 |
42 | Leaves ovate to broadly ovate; apices abruptly cuspidate to apiculate. | > 43 |
43 | Distal laminal cells multipapillose. | > 44 |
44 | Leaf margins plane. | Aschisma |
44 | Leaf margins revolute. | Tortula |
43 | Distal laminal cells smooth or with 1 conic papilla or bottle-shaped protuberances. | > 45 |
45 | Distal laminal cells bulging adaxially as bottle-shaped cells. | Microbryum |
45 | Distal laminal cells smooth or occasionally with conic papillae. | Acaulon |
42 | Leaves narrowly lanceolate to oblong; costae subpercurrent to subulate. | > 46 |
46 | Capsules pyriform, neck conspicuous. | Bruchia |
46 | Capsules globose to broadly elliptic, neck not conspicuously differentiated. | > 47 |
47 | Costae long-excurrent, at least on perichaetial leaves. | Cleistocarpidium, 25 – 8. Pleuridium |
47 | Costae subpercurrent. | > 48 |
48 | Leaf margins spinose-serrulate throughout. | Ephemerum |
48 | Leaf margins entire or serrulate distally. | > 49 |
49 | Leaves oblong-lanceolate to obovate. | Physcomitrella |
49 | Leaves lanceolate. | Pseudephemerum |
37 | Plants mostly larger, on various substrates, mostly not ephemeral, or if so, capsules exserted, protonemata not persistent or not present when mature. | > 50 |
50 | Capsule neck (hypophyses) as wide or wider than urn; on dung and animal remains. | > 51 |
51 | Capsules dumbbell shaped when mature; setae hyaline; restricted to the Arctic. | Aplodon |
51 | Capsules (at least urn) cylindric; setae pigmented; widespread. | > 52 |
52 | Hypophyses narrowly pyriform, same color or darker than urn; peristome teeth joined in 4's, later in 2's, not chambered. | Tetraplodon |
52 | Hypophyses globose to turbinate, sometimes umbrelliform, color differentiated from urn; peristome teeth sometimes approxima te or fused in pairs, chambered. | Splachnum |
50 | Capsule neck considerably narrower than urn; on various substrates. | > 53 |
53 | Leaves dimorphic, lateral ones large, dorsal ones smaller. | > 54 |
54 | Leaves bordered; stems erect; along Pacific coast. | Epipterygium |
54 | Leaves unbordered; stems prostrate; restricted to s Florida. | Racopilum |
53 | Leaves monomorphic. | > 55 |
55 | Capsules cleistocarpous; plants rare. | > 56 |
56 | New Hampshire; on wet soil. | Bruchia |
56 | Arctic and alpine tundra; on animal-derived substrates. | > 57 |
57 | Capsules broadest proximally. | Voitia |
57 | Capsules broadest distally. | Tetraplodon |
55 | Capsules operculate; plants rare to common. | > 58 |
58 | Laminal cell walls nodulose-wavy throughout leaf, sometimes most conspicuous toward leaf base when distal cells short. | > 59 |
59 | Laminal cells smooth or with raised ridges between lumina (pseudopapillae). | Bucklandiella |
59 | Laminal cells papillose or hyaline leaf awns papillose, papillae over lumina. | > 60 |
60 | Green laminal cells with tall, conic papillae over lumina. | Niphotrichum |
60 | Green laminal cells with flat papillae over longitudinal walls. | > 61 |
61 | Hyaline apices present, strongly papillose, decurrent. | Racomitrium |
61 | Hyaline apices absent, or if present never papillose or decurrent. | Codriophorus |
58 | Laminal cell walls not nodulose-wavy, or only near leaf insertion. | > 62 |
62 | Leaf hair-points absent, or if present not hyaline. | > 63 |
63 | Costae narrower, or if broad then ending below leaf apex and not filling it; or if costae broad then plants pleurocarpous. | > 64 |
64 | Plants pleurocarpous (sporophytes lateral); stems mostly prostrate with lateral branches, often mat-forming, or stems prostrate with erect branches bearing terminal sporophytes (cladocarpous). | Subkey C |
64 | Plants acrocarpous (sporophytes terminal); stems erect, not branched or occasionally branched below inflorescences. | Subkey D |
63 | Costae very broad, occupying 1/3 – 1/2 leaf base and filling subula; plants acrocarpous. | > 65 |
65 | Alar cells well differentiated. | > 66 |
66 | Costal guide cells and stereids absent, in transverse section with median layer of green cells enclosed dorsally and ventrally with hyaline cells. | Paraleucobryum |
66 | Costal guide cells and stereids usually present, without enclosed green cells. | > 67 |
67 | Inner basal laminal cells not conspicuously differentiated along costa; capsules furrowed; annuli compound; calyptrae usually fringed. | Campylopus |
67 | Inner basal laminal cells pale, enlarged, broadly rectangular, extending upward along costa; capsules smooth; annuli absent; calyptrae not fringed. | Dicranodontium |
65 | Alar cells poorly differentiated. | > 68 |
68 | Capsule neck at least as long as urn; costa filling no more tha n 1/3 leaf base. | Trematodon |
68 | Capsule neck short, inconspicuous; costa filling 1/2 or more of leaf base. | > 69 |
69 | Leaves 3.5 – 5 mm; distal laminal cells elongate, 75 – 140 µm; brood leaves absent. | Campylopodiella |
69 | Leaves 2 – 3 mm; distal laminal cells rectangular, 25 – 55 µm; brood leaves usually present, often many. | Brothera |
62 | Leaf hair-points present, hyaline. | > 70 |
70 | Costa broad, filling 1/4 or more of leaf base. | Campylopus |
70 | Costa narrower than 1/4 leaf base. | > 71 |
71 | Distal laminal cells densely multipapillose, papillae C -shaped. | > 72 |
72 | Basal laminal cell end walls thickened; calyptrae large, mitrate. | Encalypta |
72 | Basal laminal cell end walls not thickened; calyptrae small, cucullate. | > 73 |
73 | Abaxial costal surface cells thin-walled, differentiated from interior stereids; laminal reaction yellow in 2% KOH. | Tortula |
73 | Abaxial costal surface cells thick-walled, not differentiated from interior stereids; laminal reaction red to orange in 2% KOH. | > 74 |
74 | Leaf margins plane to revolute; marginal cells similar to laminal cells. | Syntrichia |
74 | Leaf margins strongly revolute; marginal cells chlorophyllose, walls thin. | Hilpertia |
71 | Distal laminal cells smooth or papillae low, indistinct. | > 75 |
75 | Laminal cells smooth, lax, hexagonal to rhombic, walls thin. | > 76 |
76 | Leaves not bordered. | Stegonia |
76 | Leaves bordered. | > 77 |
77 | Leaves ovate to broadly lanceolate; distal margins entire to serrulate. | Leptostomopsis |
77 | Leaves obovate to spathulate; distal margins serrate. | > 78 |
78 | Distalmost laminal cells quadrate to short-rectangular, 1 – 2:1; capsules erect; peristome reduced. | Brachymenium |
78 | Distalmost laminal cells rectangular, 2 – 4:1; capsules inclined to pendent; peristome well developed. | Rosulabryum |
75 | Laminal cells obscurely papillose, rounded to quadrate, walls firm. | > 79 |
79 | Plants on trees. | Orthotrichum |
79 | Plants on rock and soil. | > 80 |
80 | Perichaetial leaves differentiated from vegetative leaves in size and shape; capsules immersed. | Schistidium |
80 | Perichaetial leaves similar to distal vegetative leaves; capsules immersed or exserted. | > 81 |
81 | Calyptrae scarcely longer than operculum, cucullate or mitrate, smooth. | Grimmia |
81 | Calyptrae large, covering capsule to middle or below, campanulate-mitrate, striate or plicate. | > 82 |
82 | Leaves lanceolate; annuli absent; calyptrae plicate. | Coscinodon |
82 | Leaves ovate to obovate; annuli well developed; calyptrae striate. | Jaffueliobryum |
Subkey C
1 | Leaves bordered by elongate cells, sharply differentiated from shorter inner cells. | > 2 |
2 | Plants epiphytic; leaf borders 1-stratose. | Daltonia |
2 | Plants aquatic; leaf borders 2 – 5-stratose. | > 3 |
3 | Leaf margins serrate almost to base; leaves ovate-oblong to ovate-lanceolate; apices acuminate; Oregon. | Limbella |
3 | Leaf margins serrulate; leaves ovate, often broadly so; apices bluntly acute; e North America. | Platylomella |
1 | Leaves not bordered by elongate cells. | > 4 |
4 | Laminal cells papillose or prorulose. | > 5 |
5 | Leaves rugose, plicate. | Rhytidium |
5 | Leaves not rugose, rarely plicate. | > 6 |
6 | Laminal cells multipapillose. | > 7 |
7 | Papillae randomly arranged over cells; laminal cells ± isodiametric. | > 8 |
8 | Leaves strongly inrolled when dry; marginal basal laminal cells elongate, smooth; sporophytes terminal on branches. | Macromitrium |
8 | Leaves loosely erect to contorted when dry; marginal basal laminal cells rounded, papillose; sporophytes lateral. | Anomodon |
7 | Papillae arranged in 1 row over lumina; laminal cells longer than 3:1. | > 9 |
9 | Plants stiff, dark green to blackish; leaves ovate, plicate; bases cordate. | Papillaria |
9 | Plants soft, bright green; leaves lanceolate, not plicate; bases not cordate. | Barbella |
6 | Laminal cells 1-papillose or prorulose. | > 10 |
10 | Laminal cells 1-papillose over lumina. | > 11 |
11 | Distal laminal cells linear-flexuose; specialized asexual reproduction by 1-seriate propagula in leaf axils. | Henicodium |
11 | Distal laminal cells short, 1 – 3:1; specialized asexual reproduction absent or by branchlets. | > 12 |
12 | Leaves ovate-lanceolate, squarrose when moist; apices narrowed to smooth, pale acumen. | Lindbergia |
12 | Leaves oblong-ovate, loosely erect, ± c omplanate; apices bluntly acute. | Stereophyllum |
10 | Laminal cells prorulose. | > 13 |
13 | Laminal cells 1 – 3:1. | > 14 |
14 | Leaves little altered when moist; perichaetial leaves scarcely differentiated; capsules exserted. | Lescuraea |
14 | Leaves appressed when dry, wide-spreading when moist; perichaetial leaves strongly differentiated; capsules immersed. | > 15 |
15 | Perichaetia and capsules lateral; peristome double (single in C. ravenelii). | Cryphaea |
15 | Perichaetia and capsules terminal; peristome single. | Schoenobryum |
13 | Laminal cells more than 5:1. | > 16 |
16 | Plants epiphytic; primary stems inconspicuous, creeping, secondary stems erect; costae subpercurrent. | Pireella |
16 | Plants terrestrial and epiphytic; primary and secondary stems not differentiated; costae ending well before apex. | > 17 |
17 | Leaf bases decurrent; setae rough; capsule s inclined; usually terrestrial. | Bryhnia |
17 | Leaf bases not decurrent; setae smooth; capsules erect; epiphytic or saxicolous. | Isothecium |
4 | Laminal cells smooth. | > 18 |
18 | Leaf apices rounded-obtuse to truncate, apiculus absent. | > 19 |
19 | Leaf apices truncate. | Neckeropsis |
19 | Leaf apices rounded-obtuse. | > 20 |
20 | Distal laminal cells less than 3:1. | > 21 |
21 | Stems strongly complanate-foliate, little altered when moist; plants shiny. | Homalia |
21 | Stems at best weakly complanate-foliate, strongly incurved when dry, erect when moist; plants dull. | Leptodon |
20 | Distal laminal cells more than 5:1. | > 22 |
22 | Alar cells inflated, or well differentiated from basal cells. | > 23 |
23 | Leaves loosely spreading, slightly concave; in fens. | Calliergon |
23 | Leaves strongly julaceous, concave; in peatlands or near streams. | > 24 |
24 | Leaves oblong; apices obtuse; plants yellowish, very shiny, in peatlands. | Straminergon |
24 | Leaves ovate; apices obtuse to bluntly acute; plants brownish or green, dull or occasionally glossy, along streams and on rock. | Scleropodium |
22 | Alar cells not at all inflated, or if different from basal cells then smaller. | > 25 |
25 | Costal terminal spines present. | Oxyrrhynchium |
25 | Costal terminal spines absent. | > 26 |
26 | Leaves plane to concave, spreading to loosely imbricate; laminal cells usually more than 7:1; on wet rock; widespread. | Hygrohypnum |
26 | Leaves deeply concave, tightly imbricate; laminal cells mostly less than 7:1; terrestrial; Alaska. | Myuroclada |
18 | Leaf apices acuminate to bluntly acute, or apiculus present, minute. | > 27 |
27 | Distal laminal cells 1 – 2:1. | > 28 |
28 | Sporophytes terminal on erect branches; distal laminal cells rounded. | > 29 |
29 | Basal marginal laminal cells short, rounded-quadrate. | > 30 |
30 | Distal laminal cells not bulging; leaves oblong-lanceolate; calyptrae naked, cucullate. | Drummondia |
30 | Distal laminal cells strongly bulging; leaves lanceolate; calypt rae hairy, mitrate. | Macrocoma |
29 | Basal marginal laminal cells elongate. | > 31 |
31 | Inner basal laminal cells subquadrate to rounded; calyptrae short, plicate. | Groutiella |
31 | Inner basal laminal cells linear; calyptrae long, not plicate. | Schlotheimia |
28 | Sporophytes lateral; distal laminal cells rhombic to subquadrate. | > 32 |
32 | Costae strongly flexuose distally; leaf margins with multicellular teeth. | Herpetineuron |
32 | Costae straight or faintly flexuose; leaf margins entire to serrulate. | > 33 |
33 | Costae ending in leaf apex. | > 34 |
34 | Distal laminal cells short-oblong to rhombic, walls firm. | > 35 |
35 | Costae less than 35 µm wide at base; terrestrial. | Amblystegium |
35 | Costae mostly more than 50 µm wide at base; aquatic. | Hygroamblystegium |
34 | Distal laminal cells rounded-quadrate to elliptic, walls thick. | > 36 |
36 | B rood branchlets present, axillary. | Leskeella |
36 | Brood branchlets absent. | > 37 |
37 | Alar cells extending to costa; inner basal laminal cells not differentiated; peristome white. | Lindbergia |
37 | Alar cells in 5 or 6 rows along margins, not reaching costa; inner basal laminal cells long-rectangular; peristome yellow. | Pseudoleskeella |
33 | Costae ending well before leaf apex. | > 38 |
38 | Secondary stems erect, branched. | > 39 |
39 | Leaf apices broadly acute; leaves less than 1 mm; w North America. | Bryolawtonia |
39 | Leaf apices short-acuminate; leaves more than 1 mm; e North America. | Forsstroemia |
38 | Secondary stems not differentiated, prostrate. | > 40 |
40 | Leaf apices acuminate; leaves often homomallous. | Pseudoleskeella |
40 | Leaf apices bluntly acute; leaves erect to spreading. | > 41 |
41 | Leaves symmetric; exostome teet h rudimentary; se North America. | Clasmatodon |
41 | Leaves obliquely asymmetric at apex; exostome teeth cross striate; boreal and arctic. | Myrinia |
27 | Distal laminal cells more than 5:1. | > 42 |
42 | Plants with long, deciduous, flagelliform branches. | Pseudocryphaea |
42 | Plants without flagelliform branches. | > 43 |
43 | Primary stems inconspicuous, creeping, with reduced leaves, secondary stems erect, leafy. | > 44 |
44 | Secondary stems mostly unbranched. | Jaegerina |
44 | Secondary stems irregularly pinnate. | > 45 |
45 | Secondary stem leaf costae toothed abaxially; branch leaf apices acute. | Bestia |
45 | Costae smooth abaxially; branch leaf apices acuminate. | > 46 |
46 | Leaf margins revolute nearly throughout, serrate distally, teeth often reflexed; costae often with supplementary costae; w North America (disjunct in Newfoundland). | Antitrichia |
46 | Leaf margins reflexed, entire to serrulate; costae without supplementary costae; e North America. | Forsstroemia |
43 | Primary and secondary stems not differentiated. | > 47 |
47 | Plants aquatic, coarse; costae broad, more than 100 µm wide at base, bluntly excurrent. | > 48 |
48 | Costae ca. 1/4 width of leaf base; lamina 1-stratose throughout. | Hygroamblystegium |
48 | Costae ca. 1/3 width of leaf base; lamina with multistratose streaks. | Donrichardsia |
47 | Plants of various habitats; costae much narrower, ending before apex to excurrent, if excurrent then finely so. | > 49 |
49 | One side of stems for entire length covered by reddish rhizoidal tomentum; leaves strongly plicate. | Tomentypnum |
49 | Tomentum, if present, restricted to extreme base of stems; leaves plicate or not. | > 50 |
50 | Leaves falcate-secund. | > 51 |
51 | Stem hyalodermis present. | > 52 |
52 | Leaves strongly plicate; margins distinctly denticulate distally. | Sanionia |
52 | Leaves striolate to plane; margins entire to slightly denticulate. | > 53 |
53 | Alar cells inflated; in streams. | Hygrohypnum |
53 | Alar cells poorly differentiated; in rich fens. | Scorpidium |
51 | Stem hyalodermis absent. | > 54 |
54 | Plants of upland habitats; le aves plicate. | Brachytheciastrum, 62 – 2. Brachythecium, 62 – 17. Sciuro-hypnum complex |
54 | Plants of wet habitats; leaves not plicate. | > 55 |
55 | Leaves keeled, distinctly to obscurely 3-ranked; endostome segments connate at apices. | Dichelyma |
55 | Leaves not keeled or 3-ranked; endostome segments free. | > 56 |
56 | Costae excurrent. | > 57 |
57 | Alar cells poorly differentiated. | Drepanocladus |
57 | Alar cells abruptly inflated. | > 58 |
58 | Leaf margins entire. | Drepanocladus |
58 | Leaf margins finely denticulate. | Warnstorfia |
56 | Costae subpercurrent. | > 59 |
59 | Leaf margins finely denticulate at apex. | > 60 |
60 | Plants greenish; leaf apices acuminate. | Warnstorfia |
60 | Plants reddish; leaf apices acute, acuminate, or rounded-apiculate. | Sarmentypnum |
59 | Leaf margins entire throughout. | > 61 |
61 | Plants on rock in mountain streams. | Hygrohypnum |
61 | Plants in fens and seeps, not on rock. | > 62 |
62 | Proximal laminal cells porose; Arctic areas. | Pseudocalliergon, 61 – 4. Loeskypnum |
62 | Laminal cells porose only at extreme insertion; widespread. | > 63 |
63 | Stems with central strand present. | Drepanocladus |
63 | Stems with central strand absent. | Hamatocaulis |
50 | Leaves straight or recurved. | > 64 |
64 | Leaves 3-ranked, conduplicate. | Brachelyma |
64 | Leaves not 3-ranked or conduplicate. | > 65 |
65 | Plants pendulous from branches; stem leaf apices with capillary points; branch leaves strongly recurved; restricted to s Florida. | Zelometeorium |
65 | Plants terrestrial to epiphytic, never pendulous; stem leaf apices with shorter points; branch leaves mostly not strongly recurved; mostly n North America. | > 66 |
66 | Laminal cells long-hexagonal, less than 8:1. | > 67 |
67 | Leaves broadly ovate, deeply concave; Alaska. | Myuroclada |
67 | Leaves lanceolate to ovate, not or only slightly concave; widespread. | > 68 |
68 | Plants epiphytic. | > 69 |
69 | Leaf margins entire; apices gradually acuminate; peristome double, reflexed. | Anacamptodon |
69 | Leaf margins mostly toothed; apices piliferous; peristome single to absent. | Fabronia |
68 | Plants terrestrial and saxicolous. | > 70 |
70 | Leaf apices piliferous. | Fabronia |
70 | Leaf apices acute to acuminate. | > 71 |
71 | Distal laminal cell walls thick, ends rounded; capsules erect. | Pseudoleskeella |
71 | Distal laminal cell walls firm, ends pointed; capsules inclined. | > 72 |
72 | Plants on soil in dry habitats, especially prairies. | Brachytheciastrum |
72 | Plants on logs and soil in mesic to wet habitats. | > 73 |
73 | Leaves greater than 1 mm. | Leptodictyum |
73 | Leaves less than 1 mm. | Amblystegium |
66 | Laminal cells linear, more than 10:1. | > 74 |
74 | Plants attached to rock in fast flowing streams and beside waterfalls. | Rhynchostegium |
74 | Plants in various habitats but not on rock in fast flowing water. | > 75 |
75 | Plants terrestrial, large, coarse; stems erect, pinnate. | > 76 |
76 | Stem leaves ovate-lanceolate, acuminate to filiform, plicate; on litter in coniferous forests. | Homalothecium |
76 | Stem leaves ovate-oblong, abruptly apiculate, not plicate; in lawns and gardens. | Pseudoscleropodium |
75 | Plants various; stems variously branched, prostrate to ascending, if erect then in wetlands. | > 77 |
77 | Leaves plicate. | > 78 |
78 | Branches curved-ascending when dry. | Homalothecium |
78 | Branches prostrate. | > 79 |
79 | Leaf margins entire to serrulate at apex; distal laminal cell walls firm; alar cells mostly differentiated, short-rectangular; plants soft. | Brachytheciastrum, 62 – 2. Brachythecium, 62 – 17. Sciuro-hypnum complex |
79 | Leaf margins coarsely serrate at apex; distal laminal cell walls thick; alar cells well differentiated, quadrate; plants rigid. | Palamocladium |
77 | Leaves not plicate. | > 80 |
80 | Plants on tree trunks; calyptrae sparsely hair y; setae rough; e United States. | Homalotheciella |
80 | Plants not on tree trunks except rarely at base; calyptrae naked; setae usually smooth, rarely rough; w North America. | > 81 |
81 | Stems terete-foliate, at least at apex; leaves broadly oblong to ovate, concave to cucullate. | > 82 |
82 | Leaf apices abruptly acuminate. | > 83 |
83 | Costae with 1+ terminal spines; w North America. | Scleropodium |
83 | Costae without terminal spines; widespread. | > 84 |
84 | Leaf apices broader, twisted. | Bryoandersonia |
84 | Leaf apices filiform, flat. | Cirriphyllum |
82 | Leaf apices broadly acute to obtuse, sometimes with minute apiculus. | > 85 |
85 | Leaf apices with minute apiculus. | > 86 |
86 | Plants reddish; alar cells strongly inflated, walls thin. | Sarmentypnum |
86 | Plants green to brownish; alar cells slightly inflated, walls thick. | > 87 |
87 | Leaves imbricate or slightly falcate-apiculate in Arctic species. | Pseudocalliergon |
87 | Leaves falcate. | Loeskypnum |
85 | Leaf apices not apiculate. | > 88 |
88 | Leaf apices broadly acute; on moist rock and soil; Pacific coast. | Scleropodium |
88 | Leaf apices obtuse; in fens and swamps; widespread. | > 89 |
89 | Plants slender, wormlike, unbranched; leaves tightly imbricate. | Pseudocalliergon |
89 | Plants robust, branched; leaves loosely imbricate at least proximally. | Calliergon |
81 | Stems with spreading leaves; leaves lanceolate, not or scarcely concave. | > 90 |
90 | Branch leaf apical laminal cells 1/2 length of medial cells. | Eurhynchiastrum |
90 | Branch leaf apical laminal cells scarcely shorter than medial cells. | > 91 |
91 | Leaf apices twisted; stems often complanate-foliate. | Rhynchostegium |
91 | Leaf apices flat; stems rarely complanate-foliate. | > 92 |
92 | Leaf apices channeled; bases concave, insertions narrow. | > 93 |
93 | Leaves more than 1.6 mm, falcate to straight. | Drepanocladus |
93 | Leaves less than 1.7 mm, recurved to squarrose. | > 94 |
94 | Largest alar cells 10 – 19 µm wide; sexual condition dioicous. | Campyliadelphus |
94 | Largest alar cells 18 – 25 µm wide; sexual condition autoicous. | Pseudocampylium |
92 | Leaf apices not channeled; bases not concave, insertions not narrow. | > 95 |
95 | Alar cells many, quadrate, with more on one side of costa than the other, collenchymatous; s Florida. | Entodontopsis |
95 | Alar cells few, quadrate to rectangular, symmetrically arranged, not collenchymatous; widespread. | > 96 |
96 | Stem and branch leaves strongly differentiated; opercula long-rostrate. | Kindbergia |
96 | Stem and branch leaves scarcely differentiated; opercula conic to apiculate. | > 97 |
97 | Costae ending well below leaf apex. | > 98 |
98 | Leaves wide-spreading; margins entire; stems complanate-foliate; in wet habitats. | Leptodictyum |
98 | Leaves erect to spreading; margins serrulate, rarely entire; stems not complanat e-foliate; in various habitats. | Brachytheciastrum, 62 – 2. Brachythecium |
97 | Costae percurrent or nearly so. | > 99 |
99 | Costae indistinct at mid leaf, not toothed; setae smooth; propagula 1-seriate, often on distal abaxial costa. | Conardia |
99 | Costae distinct throughout, toothed on distal abaxial surface; setae rough; propagula absent. | Brachytheciastrum |
Subkey D
1 | Capsules large, sessile, asymmetric. | Diphyscium |
1 | Capsules smaller, usually exserted, symmetric. | > 2 |
2 | Costae with abaxial surface ridged. | > 3 |
3 | Laminal cells rounded-oblate, less than 3:1. | Grimmia |
3 | Laminal cells long-rectangular, more than 5:1. | Dicranum |
2 | Costae with abaxial surface smooth or toothed, not ridged. | > 4 |
4 | Rhizoids in conspicuous clusters, obscuring stem. | > 5 |
5 | Laminal cells strongly 1-papillose on both surfaces. | Aulacomnium |
5 | Laminal cells smooth or prorulose. | > 6 |
6 | Leaves narrowly lanceolate from ovate base. | Anacolia |
6 | Leaves ovate to broadly elliptic. | > 7 |
7 | Rhizoidal (macronematal) initials in longitudinal rows; endostome segments fused into dome. | Cinclidium |
7 | Rhizoidal initials not in longitudinal rows; endostome segments free. | Rhizomnium |
4 | Rhizoids inconspicuous or if conspicuous, never obscuring stem. | > 8 |
8 | Plants blackish, on wet rock usually near streams or sea; propagula absent. | > 9 |
9 | Leaf bases with submarginal band of elongate cells. | Scouleria |
9 | Leaf bases without differentiated submarginal cells. | > 10 |
10 | Leaf margins plane to recurved. | Schistidium |
10 | Leaf margins incurved. | Grimmia |
8 | Plants greenish, in various habitats, rarely on wet rock by streams; propagula present or absent. | > 11 |
11 | Hyaline basal cells extending up margins farther than at costa, forming V -shaped region. | > 12 |
12 | Distal laminal cells bulging but not papillose. | Luisierella |
12 | Distal laminal cells multipapillose. | > 13 |
13 | Leaves squarrose-recurved from erect base when moist; leaf margins serrulate distally; sporophytes lateral. | Pleurochaete |
13 | Leaves erect-spreading to spreading from erect base when moist; leaf margins entire to notched; sporophytes terminal. | Tortella |
11 | Hyaline basal cells if present extending ± equally up margins and costa, or farther up costa. | > 14 |
14 | Plants glaucous, bluish green; leaves narrowly lanceolate. | Saelania |
14 | Plants usually not glaucous or bluish, if so then leaves not lanceolate. | > 15 |
15 | Leaves unbordered, or if bordered then by only 1 row (or several poorly defined rows) of somewhat elongate cells, or by short cells. | > 16 |
16 | Leaf margins with single teeth or entire. | > 17 |
17 | Laminal cells smooth or papillose, not bulging, or if bulging then papillose. | Subkey E |
17 | Laminal cells strongly bulging on one or both surfaces, not papillose. | > 18 |
18 | Leaf laminae 2-stratose. | Timmiella |
18 | Leaf laminae 1-stratose. | > 19 |
19 | Leaf bases sheathing. | Timmia |
19 | Leaf bases not sheathing. | > 20 |
20 | Distal laminal cells bulging on both surfaces; calyptrae mitrate; Arctic and n North America11-1. Bryobrittonia, v. 27, p. 171 | > 20 |
20 | Distal laminal cells bulging only on adaxial surface; calyptrae cucullate; temperate distribution. | Hyophiladelphus |
16 | Leaf margins with paired teeth. | > 21 |
21 | Leaf bases with abruptly differentiated unpigmented cells (cancellinae); propagula on distal costa. | Syrrhopodon |
21 | Leaf bases without cancellinae; propagula absent. | > 22 |
22 | Laminal cells smooth. | > 23 |
23 | Leaves elliptic to ovate-elliptic. | Mnium |
23 | Leaves linear-lanceolate. | Pyrrhobryum |
22 | Laminal cells prorulose or with fine cuticular ridges. | > 24 |
24 | Distal laminal cells with cuticular ridges; stems t riangular in transverse section. | Plagiopus |
24 | Distal laminal cells prorulose; stems round in transverse section. | > 25 |
25 | Leaves crispate when dry. | Bartramia |
25 | Leaves straight when dry. | Philonotis |
15 | Leaves bordered by 2+ rows of elongate cells. | > 26 |
26 | Leaf margins entire. | > 27 |
27 | Laminal cells 1 – 2:1. | > 28 |
28 | Rhizoidal (macronematal) initials in longitudinal rows; endostome segments fused into dome. | Cinclidium |
28 | Rhizoidal initials not in longitudinal rows; endostome segments free. | > 29 |
29 | Leaves ovate or broadly elliptic; border 1-stratose; stems blackish; stomata superficial. | Cyrtomnium |
29 | Leaves obovate or elliptic, occasionally orbicular; border thickness various; stems usually reddish; stomata immersed. | Rhizomnium |
27 | Most laminal cells longer than 3:1. | > 30 |
30 | Laminal cells in oblique rows; leaf apices rounded-obtuse, usually apiculate. | Pseudobryum |
30 | Laminal cells not in obvious rows; leaf apices various. | > 31 |
31 | Distal laminal cells 3 – 6:1, longer than proximal cells; leaves imbricate, not contorted or twisted when dry; border cells 1-stratose. | > 32 |
32 | Plants mostly less than 1 cm; leaves less than 2.5 mm. | Gemmabryum |
32 | Plants mostly 1 – 3 cm; leaves 1 – 3.5 mm. | Imbribryum |
31 | Distal laminal cells 2 – 4:1, similar in length to proximal cells; leaves twisted to contorted when dry; border cells 1-or 2-stratose. | > 33 |
33 | Leaves ovate-lanceolate to ovate; border cells 1-or 2-stratose. | Ptychostomum |
33 | Leaves ovate to obovate; border cells 1-stratose. | Rosulabryum |
26 | Leaf margins toothed, sometimes obscurely so. | > 34 |
34 | Leaf bases expanded, with many abruptly hyaline cells. | Syrrhopodon |
34 | Leaf bases not expanded, without hyaline cells. | > 35 |
35 | Leaf marginal teeth paired. | > 36 |
36 | Laminal cells mammillose. | Trachycystis |
36 | Laminal cells not mammillose. | > 37 |
37 | Some leaves with low, inconspicuous lamellae; costal stereid bands 2; exostome teeth 32, attached at apices to tympanum. | Atrichum |
37 | Lamellae absent; costal stereid band 1 or absent; exostome teeth 16, free. | Mnium |
35 | Leaf marginal teeth single. | > 38 |
38 | Leaves rugose when dry or moist; restricted to Pacific Northwest. | Roellobryon |
38 | Leaves usually flat when moist, contorted but not rugose when dry; widespread. | > 39 |
39 | Laminal cells shorter than 2:1. | Plagiomnium |
39 | Laminal cells 3+:1. | > 40 |
40 | Stems rosulate-foliate, erect from horizontal underground stem; sporophytes often clustered. | Rhodobryum |
40 | Stems foliate throughout, without rhizomelike connections between erect stems; sporophytes not clustered. | > 41 |
41 | Laminal cells in oblique rows; leaf apices rounded-obtuse, usually apiculate. | Pseudobryum |
41 | Laminal cells not in obvious rows; leaf apices broadly acute to acuminate. | > 42 |
42 | Plants roselike with distinctive head of terminal leaves. | > 43 |
43 | Capsules erect, symmetric; endostome basal membrane high, segments absent or rudimentary, cilia absent. | Brachymenium |
43 | Capsules inclined, asymmetric; endostome basal membrane keeled, segments keeled, perforate, cilia usually present. | Rosulabryum |
42 | Plants with leaves evenly arranged along stem or bulbiform. | > 44 |
44 | Distal laminal cells 3 – 6:1, longer than proximal cells; leaves imbricate, not contorted or twisted when dry; border cells 1-stratose. | > 45 |
45 | Plants mostly less than 1 cm; leaves less than 2.5 mm. | Gemmabryum |
45 | Plants mostly 1 – 3 cm; leaves 1 – 3.5 mm. | Imbribryum |
44 | Distal laminal cells 2 – 4:1, similar in length to proximal cells; leaves twisted to contorted when dry; border cells 1-or 2-stratose. | > 46 |
46 | Leaves ovate-lanceolate to ovate; border cells 1-or 2-stratose. | Ptychostomum |
46 | Leaves ovate to obovate; border cells 1-stratose. | Rosulabryum |
Subkey E
1 | Leaf bases abruptly expanded, sheathing. | > 2 |
2 | Laminal cells papillose (at least on sheath) or prorulose. | > 3 |
3 | Laminal cells papillose over lumina. | Timmia |
3 | Laminal cells prorulose. | Bartramia |
2 | Laminal cells smooth. | > 4 |
4 | Distal laminal cells quadrate. | > 5 |
5 | Capsules inclined, asymmetric, strumose; widespread. | Oncophorus |
5 | Capsules erect, symmetric, not strumose; restricted to sw United States. | Symblepharis |
4 | Distal laminal cells short-rectangular. | > 6 |
6 | Leaf awns roughened throughout by projecting cell ends. | Trichodon |
6 | Leaf awns smooth or only rough at apex. | > 7 |
7 | Capsule neck as long as or longer than urn. | Trematodon |
7 | Capsule neck much shorter than urn. | > 8 |
8 | Capsules inclined, oblong, smooth or furrowed, if erect then furrowed; peristome teeth flat, split mid tooth, vertically pitted. | Dicranella |
8 | Capsules erect, cylindric, smooth; peristome teeth irregularly perforate or deeply cleft into teret e, sometimes filiform divisions | > 1 |
1 | Leaf bases not or gradually expanded, rarely sheathing. | > 9 |
9 | Alar cells enlarged, pigmented, or inflated. | > 10 |
10 | Distal and medial laminal cells with coarse, irregular cuticular ridges, resembling papillae in transverse section; capsules cylindric, smooth, erect. | > 11 |
11 | Leaves with clusters of spheric propagula at apex; leaf margins 2-stratose. | Grimmia |
11 | Leaves without propagula; leaf margins 1-stratose. | Dicranoweisia |
10 | Laminal cells without cuticular ridges; capsules various. | > 12 |
12 | Costal stereid bands 2. | Dicranum |
12 | Costal stereid bands absent. | > 13 |
13 | Capsules curved, strumose; on alpine rock. | Kiaeria |
13 | Capsules straight, not strumose; widespread. | > 14 |
14 | Capsules cylindric; usually terrestrial or on tree trunks, rarely on rock. | Dicranum |
14 | Capsules short, obovoid to pyriform; on rock. | > 15 |
15 | Capsules smooth when dry; peristome papillose. | Blindia |
15 | Capsules ribbed when dry; peristome vertically pitted-striolate proximally. | Arctoa |
9 | Alar cells scarcely differentiated. | > 16 |
16 | Laminal cells smooth. | > 17 |
17 | Asexual propagula borne on leaf surfaces. | Rhachithecium |
17 | Asexual propagula absent, axillary, or on leaf apices or specialized structures. | > 18 |
18 | Leaves ovate to obovate; apices broadly obtuse; costae ending before apex. | > 19 |
19 | Leaf apices cucullate. | Globulinella |
19 | Leaf apices not cucullate. | > 20 |
20 | Propagula large, multicellular, in leaf axils; leaves obovate; margins ciliate basally. | Oedipodium |
20 | Axillary propagula absent; leaves ovate to spatulate; margins eciliate. | > 21 |
21 | Plants small, bulbiform, on dry soil; leaves concave, imbricate. | Stegonia |
21 | Plants small to medium-sized, never bulbiform, on moist soil; leaves flat to concave, mostly not imbricate. | > 22 |
22 | Laminal cells short-rectangular, lax, walls thin; capsules erect. | > 23 |
23 | Apical marginal laminal cells short-rhombic, oblong-hexagonal internally; capsule neck not distinct; s United States. | Splachnobryum |
23 | Apical marginal laminal cells laxly rectangular, similar to internal ones; capsule neck well differentiated; n North America. | Tayloria |
22 | Laminal cells long-hexagonal, walls firm; capsules inclined to horizontal. | > 24 |
24 | Plants whitish; stems terete-foliate; distal laminal cells 7 – 9:1. | Anomobryum |
24 | Plants reddish or green; stems not terete-folia te; distal laminal cells 2 – 6:1. | Bryum |
18 | Leaves linear, ovate-lanceolate, ligulate to ovate; apices acuminate to acute or awned; costae ending below apex to excurrent. | > 25 |
25 | Leaves lanceolate to linear. | > 26 |
26 | Leaves conspicuously 4-ranked. | Conostomum |
26 | Leaves not conspicuously ranked (if 3-ranked see 35 – 3. Meesia (in part), v. 28, p. 32). | Subkey F |
25 | Leaves oblong, lingulate to ovate. | > 27 |
27 | Laminal cells rounded to quadrate, ± isodiametric. | > 28 |
28 | Leaf bases with abruptly differentiated, hyaline cells (cancellinae); apices often with propagula. | Calymperes |
28 | Leaf bases without cancellinae although sometimes gradually hyaline; apices without propagula. | > 29 |
29 | Costae subpercurrent; apices broadly acute or obtuse to rarely mucronate. | > 30 |
30 | Peristome teeth 4; propagula cups bo rne on apices of sterile shoots | > 30 |
30 | Peristome teeth 16; propagula cups absent. | > 31 |
31 | Leaves homomallous, broadly oblong to oblong-ovate; apices subacute to obtuse. | Arrhenopterum |
31 | Leaves not homomallous, oblong to lanceolate; apices mucronate to acuminate. | > 32 |
32 | Leaves broadly to narrowly lanceolate; peristome double. | Meesia |
32 | Leaves broadly oblong to spatulate; peristome single. | > 33 |
33 | Costal stereid band 1. | Scopelophila |
33 | Costal stereid bands 2. | Barbula |
29 | Costae excurrent to ending in cusp; apices cuspidate to piliferous. | > 34 |
34 | Leaf apices piliferous. | Tortula |
34 | Leaf apices cuspidate, apiculate, or acuminate. | > 35 |
35 | Leaves obovate to elliptic; apices apiculate [of 1( – 3) thick-walled cells] ; rhizoidal tubers present. | Chenia |
35 | Leaves ovate to spathulate; apices acute, mucronate, or acuminate; rhizoidal tubers absent. | > 36 |
36 | Distal marginal laminal cells differentiated from inner cells. | Microbryum |
36 | Distal marginal laminal cells similar to inner cells. | > 37 |
37 | Distal leaf margins dentate; marginal cells smaller, walls thicker than inner cells. | Hennediella |
37 | Distal leaf margins entire; marginal cells larger, walls thinner than inner cells. | Crumia |
27 | Laminal cells short-rectangular to linear. | > 38 |
38 | Plants filiform; stems julaceous (if costa not excurrent see also 42 – 1. Anomobryum (in part) , v. 28, p. 120). | Aongstroemia |
38 | Plants coarser; stems not julaceous. | > 39 |
39 | Laminal cells (5 – )7+:1; leaves generally lanceolate. | Pohlia |
39 | Laminal cells (3 – )4:1 or shorter; leaves generally ovate-lanceolate. | > 40 |
40 | Capsules horizontal to pendulous. | > 41 |
41 | Capsules curved, asymmetric, pendulous. | > 42 |
42 | Exostome teeth longer than and opposite to endostome segments. | Funaria |
42 | Exostome teeth either reduced or alternate to endostome segments. | Plagiobryum |
41 | Capsules straight, symmetric, inclined to horizontal. | > 43 |
43 | Gametophores much reduced; stems to 0.2 mm; leaves less than 1 mm; costae nearly absent; capsules subspheric to globose, less than 1 mm; stomata absent; endostome fused to exostome, cilia absent. | Discelium |
43 | Gametophores not reduced; stems and leaves larger; costae present; capsules cylindric to ovate, usually greater than 1 mm; stomata present; endostome free of exostome, cilia or endostome segments mostly present. | > 44 |
44 | Capsules short-pyriform to ovate, neck short; sporophytes lateral; peristome with endostome only. | Haplodontium |
44 | Capsules pyriform, neck long; sporophytes terminal; peristome with endostome and exostome. | > 45 |
45 | Rhizoidal tubers small, pyriform, brown, 40 – 60 µm; laminal cells less than 15 µm wide; alar cells quadrate. | Gemmabryum |
45 | Rhizoidal tubers large, spheric, red, often greater than 200 µm, or absent; laminal cells typically greater than 20 µm wide; alar cells not quadrate. | Plagiobryoides |
40 | Capsules erect. | > 46 |
46 | Peristome absent. | > 47 |
47 | Calyptrae 4-angled, sheathing entire capsule until after dehiscence. | Pyramidula |
47 | Calyptrae not angled, not sheathing or persistent. | > 48 |
48 | Capsules subcylindric or narrowly pyriform; annuli absent; exothecial cells oblong to oblong-linear; calyptrae inflated-cucullate. | Entosthodon |
48 | Capsules urceolate to broadly pyriform; annuli present; exothecial cells irregularly hexagonal; calyptrae inflated-mitrate. | Physcomitrium |
46 | Peristome present. | > 49 |
49 | Peristome of endostome only, without center line on external surface. | > 50 |
50 | Leaf margins entire. | Haplodontium |
50 | Leaf margins denticulate. | Mielichhoferia |
49 | Peristome double or of exostome only, with center line on external surface. | > 51 |
51 | Capsule neck scarcely differentiated. | > 52 |
52 | Plants of British Columbia (50° N) and south. | Entosthodon |
52 | Plants of arctic tundra. | Funaria |
51 | Capsule neck well differentiated. | > 53 |
53 | Capsule urns black, hypophyses sometimes yellow. | Tetraplodon |
53 | Capsule urns and hypophyses green to brown. | > 54 |
54 | Setae brownish, stout to slender; costae ending below apex; w, n North America. | Tayloria |
54 | Setae pale greenish white, slender; costae filling acumen; e North America. | Splachnum |
16 | Laminal cells papillose or prorulose. | > 55 |
55 | Leaves 2-stratose throughout, ligulate to oblong; apices obtuse; perichaetial leaves long-awned. | Diphyscium |
55 | Leaves 1-stratose, or if 2-stratose then not ligulate to oblong; apices acuminate, acute, or obtuse; perichaetial leaves not so differentiated. | > 56 |
56 | Laminal cells rectangular, prorulose; capsules globose, rugulose to furrowed when dry. | > 57 |
57 | Leaves strongly ranked. | Conostomum |
57 | Leaves not conspicuously ranked. | > 58 |
58 | Capsules erect, or if pendent then from curvature of seta, symmetric, rugulose when dry; peristome reduced to low membrane. | Philonotis |
58 | Capsules strongly inclined, asymmetric, furrowed; peristome more developed. | > 59 |
59 | Leaves 2-stratose at least at margins; on banks and cliffs in mesic habitats; innovative branches absent. | Bartramia |
59 | Leaves 1-stratose; on soil and rock in at least periodically wet habitats; innovative branches often present beneath inflorescences. | Philonotis |
56 | Laminal cells rounded-quadrate, 1 – multipapillose; capsules ovate to cylindric, smooth or furrowed. | > 60 |
60 | Laminal cells appearing papillose from slightly thickened walls between cells (not prorulose). | > 61 |
61 | Leaves erect, straight to curved; capsules immersed to short-exserted, ovate-cylindric; on rock. | Grimmia |
61 | Leaves crispate when dry; capsules long-exserted, cylindric; usually on logs. | Dicranoweisia |
60 | Laminal cells papillose over lumina. | > 62 |
62 | Laminal cells collenchymatous, stellate. | > 63 |
63 | Laminal cells multipapillose; leaves recurved. | Didymodon |
63 | Laminal cells 1-papillose; leaves not recurved. | Aulacomnium |
62 | Laminal cells not collenchymatous, or if so, not stellate. | > 64 |
64 | Leaves with abruptly differentiated hyaline cells occupying most of base (cancellinae), and with intramarginal border of elongate cells (teniolae), at least in proximal part of leaf; propagula usuall y present on leaf apex | > 64 |
64 | Leaves without cancellinae, or if present then never with teniolae; propagula never on leaf apices but sometimes elsewhere on leaves or in axils. | > 65 |
65 | Plants with propagula borne terminally on spec ialized stalks from stem apices. | Aulacomnium |
65 | Plants with or without various means of asexual reproduction but these never borne on stalks from stem apices. | > 66 |
66 | Plants on tree trunks or bare rock; capsules immersed to short-exserted, often ribbed. | > 67 |
67 | Calyptrae cucullate, not plicate, naked; on wet rock. | Amphidium |
67 | Calyptrae mitrate, plicate, usually hairy; on tree trunks and dry rock. | > 68 |
68 | Leaves usually little altered when dry; basal marginal laminal cells not differentiated; stomata immersed or superficial; caps ules immersed to short-exserted. | Orthotrichum |
68 | Leaves usually crispate to contorted when dry; basal marginal laminal cells with thickened transverse walls; stomata superficial; capsules short-exserted. | Ulota |
66 | Plants usually on soil, if on rock or trees then capsules long-exserted and mostly unribbed (or plants sterile). | > 69 |
69 | Costal stereid bands not differentiated. | > 70 |
70 | Laminal cell papillae C -shaped; leaves broadly spatulate. | Gymnostomiella |
70 | Laminal cell papillae simple, conic; leaves not broadly spatulate. | > 71 |
71 | Distal laminal cell papillae 4 – 7, conic. | Zygodon |
71 | Distal laminal cell papillae 3 or fewer, simple to branched. | > 72 |
72 | Leaves less than 0.6 mm, ligulate; apices rounded-obtuse; annuli of 2 or 3 rows of well-differentiated cells. | Gyroweisia |
72 | Leaves more than (0.7 – )1.5 mm, lanceolate to ovate; apices acuminate to obtuse; annuli poorly differentiated. | > 73 |
73 | Leaves usually little altered when dry; basal marginal laminal cells not differentiated; capsules immersed to short-exserted; calyptrae naked (species with contorted leaves) to hairy (species with unaltered leaves). | Orthotrichum |
73 | Leaves typically crispate to contorted when dry; basal marginal laminal cells with thickened transverse walls; capsules short-exserted; calyptrae hairy. | Ulota |
69 | Costal stereid bands differentiated. | > 74 |
74 | Costal stereid bands single, dorsal. | > 75 |
75 | Calyptrae campanulate-mitrate, covering entire capsule, often lobed at base; basal laminal cells with thickened transverse walls. | Encalypta |
75 | Calyptrae cucullate, covering only operculum and capsule apex, unlobed at base; basal laminal cells usually without thickened transverse walls. | > 76 |
76 | Leaves broadly lanceolate (from revolute leaf margins), lingulate or oblong-ovate; apices sometimes with hair-points; margins recurved to strongly revolute; laminal cell papillae stellate from stipitate base to C -shaped. | > 77 |
77 | Leaves with intramarginal band of enlarged, smooth, often orange cells. | Crumia |
77 | Leaves without differentiated intramarginal cells but sometimes with smooth, not enlarged marginal cells. | > 78 |
78 | Leaves narrowly lanceolate; margins erect, 2-stratose. | Didymodon |
78 | Leaves oblong, lingulate to ovate; margins plane to revolute, 1-stratose, or if 2-stratose then always revolute. | > 79 |
79 | Distal leaf margins broadly revolute to spirally revolute; marginal cells often more strongly chlorophyllose than medial cells. | Pseudocrossidium |
79 | Distal leaf margins plane to revolute; marginal cells undifferentiated or paler than medial cells. | > 80 |
80 | Leaves often bordered by smooth cells; peristome present. | Tortula |
80 | Leaves unbordered; peristome absent or rudimentary. | Microbryum |
76 | Leaves linear-lanceolate to lanceolate; apices never with hair-points; margins recurved to plane; laminal cell papillae conic, clavate, or branched, rarely C -shaped. | > 81 |
81 | Laminal cell papillae 4 – 7, widely spaced, small, conic; elliptic propagula present in leaf axils; peristome double; usually on trees, rarely on rock. | Zygodon |
81 | Laminal cell papillae 1 – 3( – 4), closely set, simple to branched; propagula absent; peristome single or absent; on soil and rock. | > 82 |
82 | Leaf margins serrulate distally; capsules erect to inclined, often furrowed and strumose; peristome vertically pitted-striolate. | Cynodontium |
82 | Leaf margins entire; capsules erect, never furrowed or strumose; peristome, when present, papillose. | > 83 |
83 | Basal laminal cells lax, hyaline; distal leaf margins 2-stratose throughout; peristome present. | Didymodon |
83 | Basal laminal cells firm-walled, pale but not hyaline; distal leaf margins 1-stratose or irregularly 2-stratose; peristome absent. | > 84 |
84 | Stems monopodial; archegonia on short, lateral branches; stems in transverse section rounded-triangular. | Anoectangium |
84 | Stems sympodial; archegonia terminal on main stem; stems in transverse section round. | Gymnostomum |
74 | Costal stereid bands both dorsal and ventral. | > 85 |
85 | Leaf margins abruptly serrate at shoulders. | Eucladium |
85 | Leaf margins entire at shoulders. | > 86 |
86 | Laminal cell papillae many (more than 7), minute, elliptic, over walls and lumina. | Amphidium |
86 | Laminal cell papillae fewer than 7, larger, round, only over lumina. | > 87 |
87 | Leaf margins toothed distally. | > 88 |
88 | Laminae 2-stratose; margins 1-stratose. | Rhexophyllum |
88 | Laminae 1-stratose; margins 1-or 2-stratose. | > 89 |
89 | Laminal cells bulging, mammillose to 1-papillose22-7. Dichodontium (in part), v. 27, p. 382 | > 89 |
89 | Laminal cells not bulging, multipapillose. | > 90 |
90 | Stems with central strand present. | Bryoerythrophyllum |
90 | Stems with central strand absent. | > 91 |
91 | Stems with hyalodermis present; costal adaxial surface with enlarged, papillose cells. | Trichostomum |
91 | Stems with hyalodermis absent; costal adaxial s urface with small, smooth cells. | Leptodontium |
87 | Leaf margins entire or roughened with projecting papillae. | > 92 |
92 | Leaf margins at extreme apex with large, curved, projecting papillae. | Dichodontium |
92 | Leaf margins at extreme apex entire or papillose-crenulate. | > 93 |
93 | Stems triquetrous, especially when moist; laminal cells 1-papillose, papillae sometimes branched; California. | Triquetrella |
93 | Stems without ranked leaves; laminal cells multipapillose; widespread. | > 94 |
94 | Leaf margins recurved to revolute, at least near mid leaf or below. | > 95 |
95 | Peristome absent; leaves recurved only on one side. | Hymenostylium |
95 | Peristome usually present; leaves recurved on both sides. | > 96 |
96 | Axillary hairs with all cells hyaline; laminal cells obscure in surface view; leaves usually ovate to oblong; costal abaxial surface cells oblong to elongate; basal laminal cells usually strongly differentiated, hyaline, elongate. | Barbula |
96 | Axillary hairs with brown basal cell; laminal cells well defined in surface view; leaves usually lanceolate; costal abaxial surface cells quadrate to short-oblong, rarely elongate; basal laminal cells usually little differentiated, green, short-rectangular. | Didymodon |
94 | Leaf margins plane to erect. | > 97 |
97 | Costae sinuous distally. | Bellibarbula |
97 | Costae straight distally. | > 98 |
98 | Stems with hyalodermis present. | Trichostomum |
98 | Stems with hyalodermis absent, epidermal cells small. | > 99 |
99 | Leaf apices subtubulose; distal laminal cell papillae 1 or 2, large, centered, multifid. | Tuerckheimia |
99 | Leaf apices flat; distal laminal cell papillae 3 – 6, small, scattered, simple, blunt. | > 100 |
100 | Perichaetia and sporophytes terminal; leaves less than 2 mm; axillary hairs of 8 – 10 cells. | Gymnostomum |
100 | Perichaetia and sporophytes lateral; leaves 2.2 – 3 mm; axillary hairs of 15 – 20 cells. | Molendoa |
Subkey F
1 | Laminal cells (3 – )4+:1, rectangular to long-hexagonal. | > 2 |
2 | Leaf apices acute to acuminate. | > 3 |
3 | Costae occupying 1/2 or more of leaf base; capsules curved, asymmetric, elongate-pyriform, neck as long as urn. | Amblyodon |
3 | Costae occupying less than 1/4 leaf base; capsules straight, symmetric, shape variable but not elongate-pyriform, neck inconspicuous. | > 4 |
4 | Plants small, less than 2 mm, gregarious, on calcareous rock; capsules ovate. | Seligeria |
4 | Plants larger, mostly more than 5 mm, in tufts, on various substrates; capsules cylindric. | > 5 |
5 | Leaves flexuose-twisted when dry; capsules er ect; s Appalachians, California. | Orthodontium |
5 | Leaves erect, little altered when dry; capsules erect or inclined; widespread. | > 6 |
6 | Capsules appearing lateral, erect; peristome single; leaves less than 1 mm; propagula absent. | Mielichhoferia |
6 | Capsules terminal, inclined to pendent; peristome double; leaves usually more than 1 mm; axillary propagula sometimes present. | Pohlia |
2 | Leaf apices subulate. | > 7 |
7 | Capsules curved, asymmetric. | Dicranella |
7 | Capsules straight, symmetric (sometimes inclined to pendulous). | > 8 |
8 | Setae flexuose-curved to cygneous. | > 9 |
9 | Setae more than 1 cm; plants more than 5 mm; leaves more than 4 mm; capsules pyriform. | Leptobryum |
9 | Setae less than 0.5 cm; plants less than 3 mm; leaves less than 2 mm; capsules hemispheric. | > 10 |
10 | Plants perennial, on rock, not in Florida; setae slender, twisted; peristome present. | Seligeria |
10 | Plants ephemeral, on soil in Florida; setae stout, curved at apex, not twisted; peristome absent. | Eccremidium |
8 | Setae straight but sometimes spirally twisted. | > 11 |
11 | Peristome double; Arctic areas. | Pseudoditrichum |
11 | Peristome single; widespread. | > 12 |
12 | Capsules ovoid; on calcareous rock. | Seligeria |
12 | Capsules oblong to cylindric; generally on soil. | > 13 |
13 | Capsules short-cylindric; peristome teeth divided 1/2 their length, flat, vertically pitted-striolate. | Dicranella |
13 | Capsules long-cylindric; peristome teeth divided to base, terete, papillose. | Ditrichum |
1 | Laminal cells 1( – 2):1, rounded to quadrate. | > 14 |
14 | Perichaetial leaves strongly differentiated, awns as long as lamina; leaves 2-stratose. | Diphyscium |
14 | Perichaetial leaves slightly or not differentiated, never long-awned; leaves 1 – multistratose. | > 15 |
15 | Distal laminal cells in ascending oblique rows; cylindric brood bodies present on leaves; tomentum common. | Zygodon |
15 | Distal laminal cells not in oblique rows; brood bodies present or absent; tomentum absent or sparse. | > 16 |
16 | Capsules distinctly 8-or 16-ribbed and furrowed. | > 17 |
17 | Calyptrae mitrate. | > 18 |
18 | Calyptrae hairy. | Ulota |
18 | Calyptrae naked. | > 19 |
19 | Annuli compound; calyptrae not plicate. | Brachydontium |
19 | Annuli absent; calyptrae plicate. | Orthotrichum |
17 | Calyptrae cucullate. | > 20 |
20 | Setae cygneous; plants rare, in tight cushions on alpine slopes22-14. Oreas, v. 27, p. 425 | > 20 |
20 | Setae erect (sometimes twisted); plants various but not as above. | > 21 |
21 | Capsules abruptly bent at seta-capsule junction and horizontal, often purple-red when mature. | Ceratodon |
21 | Capsules erect to suberect, brown when mature. | > 22 |
22 | Peristome teeth divided to 1/2 their length; capsules cylindric to ovate-cylindric, 2 mm; Pacific Northwest. | Cynodontium |
22 | Peristome teeth undivided; capsules ovoid, less than 1 mm; e, Midwestern United States, maritime Canada22-16. Rhabdoweisia, v. 27, p. 428 | > 16 |
16 | Capsules smooth, or indistinctly furrowed when dry but without distinct ribs. | > 23 |
23 | Capsule neck elongate, well defined; peristome double. | Meesia |
23 | Capsule neck short, inconspicuous; peristome single. | > 24 |
24 | Capsules inclined. | > 25 |
25 | Capsules 1.5 – 2 mm, pale, strumose; leaf margins 2-stratose; on moist soil, rock, and logs. | Oncophorus |
25 | Capsules less than 1 mm, black, not strumose; leaf margins 1-stratose; in rich fens. | Catoscopium |
24 | Capsules erect. | > 26 |
26 | Capsules immersed to short-exserted. | Grimmia |
26 | Capsules long-exserted. | > 27 |
27 | Calyptrae mitrate. | > 28 |
28 | Calyptrae not plicate; setae cygneous. | Campylostelium |
28 | Calyptrae plicate; setae straight. | Ptychomitrium |
27 | Calyptrae cucullate. | > 29 |
29 | Leaves oblong. | Barbula |
29 | Leaves lanceolate from somewhat expanded base. | Didymodon |