Ptychostomum warneum

(Röhling) J. R. Spence

Phytologia 87: 22. 2005.

Basionym: Mnium caespiticium var. warneum Röhling Deutschl. Fl. ed. 2, 3: 94. 1813
Synonyms: Bryum warneum
Treatment appears in FNA Volume 28. Treatment on page 174. Mentioned on page 167.

Plants in dense or open turfs, red, green, or yellow-green. Stems 0.5–2(–3) cm, fertile stems comose, innovations evenly foliate. Leaves yellow-green to red, crowded, strongly contorted to shrunken when dry, ovate-lanceolate, flat, 0.5–2 mm, often gradually enlarged toward stem apex; base usually green, not decurrent; margins revolute proximally, limbidium strong, in 2 or 3 rows; apex acuminate; costa short-excurrent, awn slender; proximal laminal cells rectangular, 3–4:1; medial and distal cells 18–22 µm wide, 2–3:1, walls thin. Specialized asexual reproduction absent. Sexual condition usually polyoicous, sometimes autoicous. Seta purple or red, 2–4(–5) cm, stout, straight to somewhat flexuose. Capsule yellow-brown or brown, pyriform, symmetric, 2–4 mm, mouth yellow; hypophysis slender; operculum long-conic; peristome reduced; exostome teeth yellow or brown basally, pale yellow to hyaline distally, lamellae straight, pores absent near base along mid line; endostome weakly adherent to exostome, basal membrane 1/2 exostome height, segments narrowly perforate, cilia absent or rudimentary. Spores with size variable in same capsule, (32–)36–48(–50) µm, pale green or yellow.


Phenology: Capsules mature Jul–Aug.
Habitat: Damp soil
Elevation: low elevations (0-50 m)

Distribution

V28 278-distribution-map.gif

Greenland, Que., n Eurasia (Himalayan Nepal).

Discussion

Ptychostomum warneum is an arctic-boreal species that is distinguished from the related P. calophyllum by its pyriform brown capsule with a slender neck, generally larger spores, and acuminate leaves. The stems are sparsely radiculose; the costal awns are smooth. The species is known from only one location in Quebec, in the Mingan Islands. Capsules are needed for identification.

Selected References

None.

Lower Taxa

None.