Skeleton Guide to the Pleurocarps

A Perspective Oriented Guide for the Identification of North American Moss Genera
Home	Overview	Abbreviated Overview	Concordance	Geographical Abbreviations

Skeleton to Freely Branched (mostly pleurocarpous) Mosses Revised through 16 November 2009 *Reminder* - a dagger (†) indicates that not all of the species within the given genus have the character(s) defining that Group.
Group P1 – Shoots strongly flattened (complanate) or angular (Sub-Guide)
Brachelyma	Homalia	Neckera
Brotherella	Homaliadelphus	Neckeropsis
Callicladium	Hookeria	Plagiothecium†
Callicostella	Isopterygiopsis	Porotrichum
Cyclodictyon	Isopterygium	Pseudotaxiphyllum
Entodon†	Lepidopilum	Racopilum
Fontinalis†	Leptodictyum†	Steerecleus
Herzogiella†	Metaneckera	Taxiphyllum
Group P2 – Shoots julaceous (both wet and dry) - shoots round with crowded, overlapping & appressed leaves (Sub-Guide)
Antitrichia†	Leucodon†	Pterogonium
Bryoandersonia	Myurella	Scleropodium†
Cryphaea	Plagiobryum	Scorpidium
Entodon†	Pseudoscleropodium	Thelia
Hedwigia
Group P3 – Leaves spreading at right angles (squarrose) or squarrose-recurved (Sub-Guide)
Campylium†	Rhytidiadelphus
Group P4 – Plants with erect branches from a creeping stem (Sub-Guide)
Bestia	Groutiella	Macromitrium
Drummondia	Jaegerina	Neomacounia
Forsstroemia	Macrocoma	Schlotheimia
Group P5 – Plants with leaves sickle-shaped and turned to one side (falcate-secund) (Sub-Guide)
Brachythecium†	Hygrohypnum†	Pylaisiadelpha
Brotherella	Hypnum	Rhytidiopsis
Ctenidium	Limprichtia	Rhytidium
Dichelyma	Loeskypnum†	Sanionia
Drepanocladus†	Palustriella	Scorpidium
Gollania	Platygyrium	Sematophyllum
Hamatocaulis	Ptilium	Warnstorfia
Heterophyllum	Pylaisiella
Group P6 – Plants with paraphyllia or tomentum on stem (Sub-Guide)
Abietinella	Helodium	Pseudoleskea
Alsia	Hylocomiastrum	Rauiella
Bryohaplocladium	Hylocomium	Rhytidiopsis
Climacium	Lescuraea	Thelia
Cratoneuron	Loeskeobryum	Thuidium
Cyrto-hypnum	Metaneckera	Tomentypnum
Dendroalsia	Palustriella
Group P7 – Plants with red stems (Sub-Guide)
Antitrichia	Hylocomium	Plagiobryum
Calliergonella	Hypnum	Pleurozium
Climacium	Loeskeobryum	Rhytidiadelphus
Hedwigia
Group P8 – Plants with shoots flat on top and appearing “braided” (Sub-Guide)
Brotherella	Hypnum†	Ptilium
Ctenidium
Group P9 – Leaves undulate or rugose (irregular undulations) (Sub-Guide)
Metaneckera	Rhytidiopsis	Schlotheimia†
Neckera†	Rhytidium	Scorpidium
Group P10 – Leaves dimorphic (two forms on the same axis) (Sub-Guide)
Hypopterygium	Racopilum
Group P11 – Leaves with awns, hair-points, or hyaline apices (Sub-Guide)
Braunia	Hedwigia	Racomitrium†
Cirriphyllum	Iwatsukiella	Wijkia
Claopodium†	Pseudobraunia	Zelometeorium
Group P12 – Plants thread-like (leaves < 1mm) (Sub-Guide)
Homomallium	Platydictya	Pseudoleskeella
Group P13 – Costa double and more than 1/3 leaf length (Sub-Guide)
Callicostella	Hylocomiastrum†	Plagiothecium†
Cyclodictyon	Hylocomium	Pseudocalliergon
Heterocladium†	Lepidopilum	Rhytidiadelphus†
Hygrohypnum†	Loeskeobryum	Trachyxiphium
Group P14 – Costa single and narrow; leaves with distinct decurrencies (Sub-Guide)
Anomodon†	Bryhnia	Heterocladium†
Brachythecium†	Eurhynchium†	Pleuroziopsis
Group P15 – Costa single and narrow; leaves with a distinct marginal border (Sub-Guide)
Brachelyma	Helodium†	Platylomella
Daltonia	Limbella	Thelia
Groutiella
Group P16 – Costa single and narrow; leaves with distinct alar cells (Sub-Guide)
Bestia	Drepanocladus	Loeskypnum
Brachythecium	Entodontopsis	Palamocladium
Calliergon	Forsstroemia†	Palustriella
Campylium†	Hygrohypnum	Pseudoscleropodium
Clasmatodon	Isothecium	Sarmenthypnum
Cratoneuron	Lindbergia	Stereophyllum
Group P17 – Costa short and double or none; leaves withdistinct decurrencies (Sub-Guide)
Herzogiella†	Heterocladium†	Plagiothecium
Group P18 – Costa short and double, or none; leaves bordered (Sub-Guide)
Groutiella	Thelia
Group P19 – Costa short and double, or none; leaves with distinct alar cells (Sub-Guide)
Acroporium	Herzogiella†	Ptilium
Alsia	Heterophyllium	Pylaisiadelpha
Brotherella	Hygrohypnum	Pylaisiella
Callicladium	Hypnum	Rhytidiadelphus†
Calliergonella	Isopterygium	Scorpidium
Campylium†	Leptopterigynandrum	Sematophyllum
Donnellia	Leucodon	Taxiphyllum†
Entodon	Platygyrium	Tripterocladium
Forsstroemia†	Pleurozium	Wijkia
Gollania	Pterogonium
Group P20 – Costa of uncommon or variable form (Sub-Guide)
Alsia	Hygrohypnum	Platyhypnidium†
Antitrichia	Isothecium	Pseudocalliergon
Calliergon	Jaegerina	Pseudoleskeella†
Drepanocladus†	Leptopterigynandrum	Pseudoscleropodium
Donrichardsia	Myurella†	Taxiphyllum
Forsstroemia†	Neomacounia	Thelia†
Heterocladium†	Plagiothecium
Note - In the following Groups, all possible genera are listed to give perspective on the Freely branched mosses. Only the genera NOT in brackets [--] are keyed out in Groups P21-P28; the genera in brackets should be identifiable using the criteria characteristic of the previous Groups. Reminder - Definitions for cell length to breadth ratios are found in the Introduction, the Overview & at the end of this section.
Group P21 – Cells long (>8:1); distinctly papillose or prorulose (Sub-Guide)
Bryhnia†	Chryso-hypnum	Homalothecium†

[Hylocomium]	[Rhytidium]	[Taxiphyllum]
Group P22 – Cells long; smooth or indistinctly ornamented^#; costa single (long and narrow) (Sub-Guide)
Brachythecium†	Homalotheciella	Scleropodium†
Conardia	Homalothecium†	Steerecleus
Dichelyma	Leptodictyum†	Stereophyllum†
Eurhynchium	Platyhypnidium	Trachybryum

[Bryoandersonia]	[Entodontopsis]	[Pleuroziopsis]
[Calliergon]	[Hamatocaulis]	[Pseudoscleropodium]
[Campylium]	[Hygrohypnum]	[Sanionia]
[Cirriphyllum	[Limbella]	[Sarmenthypnum]
[Drepanocladus	[Limprichtia]	[Warnstorfia]
[Entodon]	[Loeskypnum]
^#Note - cells indistinctly papillose, i.e., low papillae, or prorulose.
Group P23 – Cells long; smooth or indistinctly ornamented^#; costa double (long or short) or none (Sub-Guide)
*Costa long & double*
Loeskeobryum

[Hylocomiastrum]	[Rhytidiadelphus]	[Trachyxiphium]
*Costa short & double, or none*
Fontinalis	Isopterygium	Pseudotaxiphyllum
Herzogiella	Orthothecium	Taxiphyllum
Isopterygiopsis

[Brotherella]	[Hylocomium]	[Pylaisiadelpha]
[Callicladium]	[Hypnum]	[Rhytidiadelphus]
[Calliergonella]	[Plagiothecium]	[Rhytidiopsis]
[Campylium]	[Pleurozium]	[Scorpidium]
[Gollania]	[Ptilium]	[Sematophyllum]
[Hygrohypnum]
Group P24 – Cells intermediate (3-8:1); distinctly papillose or prorulose (Sub-Guide)
*Papillose*
Barbella	Papillaria	Taxithelium
Henicodium

[Antitrichia]	[Helodium]
*Prorulose*
Leptohymenium	Pireella	Pterigynandrum
Lescuraea†

[Bryhnia]	[Helodium]	[Porotrichum]
[Ctenidium]	[Hylocomium]	[Rhytidiadelphus]
[Dendroalsia]	[Isothecium]	[Rhytidium]
Group P25 – Cells intermediate; smooth or indistinctly ornamented^#; costa single (wide or narrow) (Sub-Guide)
*Costa wide*
[Donrichardsia]
*Costa narrow*
Amblystegium†	Fabronia	Pseudocryphaea
Anacamptodon	Hygroamblystegium†	Sarmenthypnum
Brachythecium†	Leptodictyum†	Scleropodium
Dichelyma	Myuroclada	Trachybryum
Eurhynchium	Pireella

[Brachelyma]	[Hamatocaulis]	[Plagiobryum]
[Calliergon]	[Homalia]	[Porotrichum]
[Campylium]	[Hygrohypnum]	[Pseudoleskeella]
[Climacium]	[Jaegerina]	[Sanionia]
[Conardia]	[Limprichtia]	[Tomentypnum]
[Cratoneuron]	[Metaneckera]	[Warnstorfia]
[Daltonia]	[Palamocladium]	[Wijkia]
[Drepanocladus]	[Palustriella]	[Zelometeorium]
[Forsstroemia]
^#Note - cells indistinctly papillose, i.e., low papillae, or prorulose.
Group P26 – Cells intermediate; smooth or indistinctly ornamented^#; costa double (long or short) or none (Sub-Guide)
*Costa long & double*
Heterocladium†		[Hylocomiastrum]
*Costa short & double, or none*
Acroporium	Iwatsukiella	Pseudocalliergon
Bryocrumia	Orthothecium	Vesicularia
Fontinalis

[Alsia]	[Homomallium]	[Platygyrium]
[Campylium]	[Hygrohypnum]	[Pseudoleskeella]
[Donnellia]	[Hypnum]	[Pterogonium]
[Entodon]	[Neckera]	[Pylaisiella]
[Forsstroemia]	[Neomacounia]	[Sematophyllum]
[Heterocladium]	[Plagiothecium]	[Tripterocladium]
[Heterophyllium]	[Platydictya]	[Zelometeorium]
Group P27 – Cells short (<3:1); distinctly papillose or prorulose (Sub-Guide)
*Papillose*
Anomodon	Haplohymenium	Lindbergia†
Braunia	Heterocladium†	Myurella†
Claopodium	Leskea†	Racomitrium

[Abietinella]	[Cyclodictyon]	[Pseudoleskea]
[Hedwigia]	[Cyrto-hypnum]	[Rauiella]
[Bryohaplocladium]	[Leptopterigynandrum]	[Thelia]
[Callicostella]	[Pseudobraunia]	[Thuidium]
*Prorulose*
Heterocladium†	Schwetschkeopsis

[Dendroalsia]	[Porotrichum]
Group P28 – Cells short; smooth or indistinctly ornamented^# (Sub-Guide)
*Costa single, long & narrow.*
Amblystegium†	Hygroamblystegium†	Lindbergia†
Bestia	Leptodon	Myrinia
Clasmatodon	Leskea†	Racomitrium
Cryphaea†	Leskeella	Stereophyllum
Herpetineuron

[Forsstroemia]	[Macrocoma]	[Pseudoleskeella]
[Groutiella]	[Macromitrium]	[Racopilum]
[Heterocladium]	[Neckeropsis]	[Schlotheimia]
[Hypopterygium]	[Platylomella]	[Thamnobryum]
[Isothecium]	[Porotrichum]
*Costa short & double, or none.*
Iwatsukiella	Myurella†	Vesicularia

[Donnellia]	[Hookeria]	[Platydictya]
[Drummondia]	[Lepidopilum]	[Pseudoleskeella]
[Forsstroemia]	[Leucodon]	[Sematophyllum]
[Homaliadelphus]	[Neckeropsis]

^#Note - cells indistinctly papillose, i.e., low papillae, or prorulose.

Cells = medial, laminal cells; cells ~2/3 of the way from insertion to apex, midway between the costa and the margin. Cell length to breadth ratio: Long cells: >8:1; commonly termed linear or linear-flexuose. Intermediate cells: 3-8:1; commonly termed elongated, oblong-rhomboidal, fusiform, or elliptical. Short cells: <3:1; commonly termed isodiametric, quadrate, rounded-quadrate, or rhombic.

Home	Overview	Abbreviated Overview	Concordance	Geographical Abbreviations

Skeleton to Freely Branched (mostly pleurocarpous) Mosses

Group P1 – Shoots strongly flattened (complanate) or angular (Sub-Guide)

Group P2 – Shoots julaceous (both wet and dry) - shoots round with crowded, overlapping & appressed leaves (Sub-Guide)

Group P3 – Leaves spreading at right angles (squarrose) or squarrose-recurved (Sub-Guide)

Group P4 – Plants with erect branches from a creeping stem (Sub-Guide)

Group P5 – Plants with leaves sickle-shaped and turned to one side (falcate-secund) (Sub-Guide)

Group P6 – Plants with paraphyllia or tomentum on stem (Sub-Guide)

Group P7 – Plants with red stems (Sub-Guide)

Group P8 – Plants with shoots flat on top and appearing “braided” (Sub-Guide)

Group P9 – Leaves undulate or rugose (irregular undulations) (Sub-Guide)

Group P10 – Leaves dimorphic (two forms on the same axis) (Sub-Guide)

Group P11 – Leaves with awns, hair-points, or hyaline apices (Sub-Guide)

Group P12 – Plants thread-like (leaves < 1mm) (Sub-Guide)

Group P13 – Costa double and more than 1/3 leaf length (Sub-Guide)

Group P14 – Costa single and narrow; leaves with distinct decurrencies (Sub-Guide)

Group P15 – Costa single and narrow; leaves with a distinct marginal border (Sub-Guide)

Group P16 – Costa single and narrow; leaves with distinct alar cells (Sub-Guide)

Group P17 – Costa short and double or none; leaves withdistinct decurrencies (Sub-Guide)

Group P18 – Costa short and double, or none; leaves bordered (Sub-Guide)

Group P19 – Costa short and double, or none; leaves with distinct alar cells (Sub-Guide)

Group P20 – Costa of uncommon or variable form (Sub-Guide)

Group P21 – Cells long (>8:1); distinctly papillose or prorulose (Sub-Guide)

Group P22 – Cells long; smooth or indistinctly ornamented#;costa single (long and narrow) (Sub-Guide)

Group P23 – Cells long; smooth or indistinctly ornamented#; costa double (long or short) or none (Sub-Guide)

Group P24 – Cells intermediate (3-8:1); distinctly papillose or prorulose (Sub-Guide)

Papillose

Prorulose

Group P25 – Cells intermediate; smooth or indistinctly ornamented#; costa single (wide or narrow) (Sub-Guide)

Costa wide

Costa narrow

Group P26 – Cells intermediate; smooth or indistinctly ornamented#; costa double (long or short) or none (Sub-Guide)

Costa long & double

Costa short & double, or none

Group P27 – Cells short (<3:1); distinctly papillose or prorulose (Sub-Guide)

Papillose

Prorulose

Group P28 – Cells short; smooth or indistinctly ornamented# (Sub-Guide)

Costa single, long & narrow.

Costa short & double, or none.

Group P2 – Shoots julaceous (both wet and dry) - shoots round with
crowded, overlapping & appressed leaves (Sub-Guide)

Group P22 – Cells long; smooth or indistinctly ornamented^#;
costa single (long and narrow) (Sub-Guide)

Group P23 – Cells long; smooth or indistinctly ornamented^#;
costa double (long or short) or none (Sub-Guide)

Group P25 – Cells intermediate; smooth or indistinctly ornamented^#;
costa single (wide or narrow) (Sub-Guide)

Group P26 – Cells intermediate; smooth or indistinctly ornamented^#;
costa double (long or short) or none (Sub-Guide)

Group P28 – Cells short; smooth or indistinctly ornamented^# (Sub-Guide)