Bryhnia

Plants small to medium-sized, in moderately loose to dense tufts, green or yellowish to brownish. Stems creeping to ascending, not attenuate, unevenly foliate, julaceous or not, irregularly to regularly pinnate, branches moderately densely terete- to complanate-foliate, sometimes julaceous; central strand present; pseudoparaphyllia acute; axillary hairs of 3 or 4 cells. Stem leaves erect, patent, or rigidly spreading, imbricate-appressed, ovate, ovate-triangular, or lanceolate, moderately to strongly concave, not or slightly plicate; base decurrent; margins serrulate proximally, serrate distally; apex gradually tapered, acute, acuminate, truncate, apiculate, or cucullate; costa to 40–80% leaf length, broad throughout, terminal abaxial spine present or absent; alar cells subquadrate to short-rectangular, large; laminal cells elongate-flexuose, walls moderately to strongly thick, prorate; basal cells shorter, wider. Branch leaves smaller, narrower; apex acute to acuminate (sharper than stem leaves); costal abaxial surface more strongly serrate; laminal cells more strongly prorate. Sexual condition dioicous; perichaetial leaf acumen reflexed. Seta brownish orange to red-brown, rough. Capsule inclined to horizontal, brownish orange to red-brown, cylindric, not or slightly curved; annulus separating by fragments; operculum long-conic, broadly rostrate; peristome xerocastique, perfect. Calyptra naked. Spores 13–18 µm.

Distribution

North America, Eurasia.

Discussion

Species 5–7 (3 in the flora).

The circumscription of Bryhnia needs a re-evaluation with DNA markers since morphology seems to be misleading. In Japan and adjacent areas, N. Takaki (1956) accepted 15 species within Bryhnia, but only six survived the revision by A. Noguchi and Z. Iwatsuki (1987+); most were synonymized with B. novae-angliae. Among North American species, B. graminicolor is not closely related to the core group and possibly should be segregated in its own genus.

Selected References

None.

Lower Taxa

Bryhnia graminicolor, Bryhnia hultenii, Bryhnia novae-angliae

Key

1	Plants small; stems to 2 cm; stem leaves narrowly ovate to lanceolate, 0.6-1.1 × 0.2-0.5 mm.	Bryhnia graminicolor
1	Plants medium-sized; stems 2.5-10 cm; stem leaves broadly ovate-triangular to ovate, 0.7-1.3(-1.6) × 0.7-1.2 mm	> 2
2	Stem leaves ovate-triangular to ovate, 1-1.3(-1.6) × 0.7-1.1 mm, longer than broad; apices acute or acuminate, rarely cucullate; stems rarely julaceous along some portions; alar regions gradually differentiated; e North America.	Bryhnia novae-angliae
2	Stem leaves broadly ovate-triangular, 0.7-1.2 × 0.8-1.2 mm, often shorter than broad; apices broadly acute to rounded-truncate and short-apiculate, often cucullate; stems julaceous; alar regions abruptly differentiated; Alaska, British Columbia.	Bryhnia hultenii