Dicranum rhabdocarpum

Sullivant

Mem. Amer. Acad. Arts, n. s. 4: 172. 1849,.

Synonyms: Orthodicranum rhabdocarpum (Sullivant) Holzinger
Treatment appears in FNA Volume 27. Treatment on page 406. Mentioned on page 398, 399.

Plants in dense tufts, green to yellowish green or brownish, ± glossy. Stems 2–8 cm, tomentose with reddish-brown rhizoids. Leaves straight or nearly so, spreading, little changed when dry, smooth, 3–5.5 × 0.6–1.2 mm, concave or tubulose proximally, tubulose to slightly keeled above; ovatelanceolate, apex obtusely acute; margins serrate near apex; laminae 1-stratose; costa subpercurrent to percurrent, 1/10–1/8 the width of the leaves at base, smooth or weakly toothed on abaxial surface near apex, with a row of guide cells, two weak stereid bands, at least in basal part of leaf, adaxial and abaxial epidermal layers of cells not differentiated; cell-walls between lamina cells not bulging; leaf cells smooth; alar cells 1-stratose or 2-stratose in part, differentiated, not extending to costa; proximal laminal cells linear-rectangular, pitted, (45–) 65–120 (–150) × (13–) 16–17 (–19) µm; distal laminal cells shorter, narrow, pitted or with few pits, (20–) 30–45 (–60) × (5–) 8–10 (–13) µm. Sexual condition dioicous; male plants about as large as the female or slightly smaller; interior perichaetial leaves ± abruptly acuminate, convolute-sheathing. Seta 1.5–3 cm, solitary, rarely two per perichaetium, yellow to reddish-brown. Capsule 1.5–4 mm, erect, straight or nearly so, furrowed when dry, brown; operculum 1.6–2.8 mm. Spores 13–19 µm.


Phenology: Capsules mature summer.
Habitat: Soil, soil over rock, peaty soil or rotten wood
Elevation: 1600-3300 m

Distribution

V27 575-distribution-map.gif

Ariz., Colo., N.Mex., Wyo., Mexico (Chihuahua), Mexico (Tamaulipas), West Indies (Dominican Republic), Central America (Guatemala)

Discussion

Dicranum rhabdocarpum is an easily recognized species that occurs in the flora area only in the Rocky Mountains and the mountains of Arizona. It is the only species in the section Dicranum that has erect, straight to weakly arcuate capsules. Other important distinguishing features are the ovate-lanceolate, straight, obtusely acute, 1-stratose leaves with alar cells 1- or 2-stratose in part and the subpercurrent to percurrent costae that are smooth or weakly toothed on the abaxial surface near the leaf apex. Dicranum rhabdocarpum has been placed in the segregate genus Orthodicranum by J. M. Holzinger (1925b) and other bryologists mainly because of its straight and erect capsules. However, it differs from taxa commonly placed in that genus, i.e., D. flagellare, D. fulvum, D. montanum, D. strictum, and D. viride, by the elongate, pitted cells and the alar cells that are sometimes 2-stratose.

Selected References

None.

Lower Taxa

None.

... more about "Dicranum rhabdocarpum"
persistent +  and deciduous +
differentiated +
Robert R. Ireland Jr. +
Sullivant +
short to long +
differentiated +
microphyllous +
pseudomonoicous +, dioicous +, autoicous +  and sexual +
flagelliform +  and terete +
reproduction +  and asexual +
cucullate +
nearly +  and straight +
cylindric +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
2-stratose +  and 1-stratose +
generally orange +  and brown +
specialized +
papillose +  and mammillose +
pseudomonoicous +, dioicous +  and sexual +
inflated +
differentiated +
subpercurrent +
1/10 +  and 1/8 +
toothed +
with few pits +  and pitted +
dioicous +  and sexual +
spreading +, erect-patent +  and erect-appressed +
smooth +  and rugose +
Ariz. +, Colo. +, N.Mex. +, Wyo. +, Mexico (Chihuahua) +, Mexico (Tamaulipas) +, West Indies (Dominican Republic) +  and Central America (Guatemala) +
reddish-brown +  and pitted-striolate +
1600-3300 m +
Soil, soil over rock, peaty soil or rotten wood +
enlarged +
falcate-secund +
papillose +, mammillose +, nonpitted +  and pitted +
nearly +  and straight +
3mm;5.5mm +
ovatelanceolate +, tubulose +  and slightly keeled +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (?) +  and 0.12 cm1.2 mm <br />0.0012 m <br /> (?) +
arcuate +  and straight +
long-rostrate +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
nonpitted +  and pitted +
toothed +  and forked +
short-acuminate +, concave +  and ovate +
pitted-striolate +
16 +  and single +
papillose +  and striolate +
Capsules mature summer. +
8um;10um +
undifferentiated +
linear-rectangular +
Mem. Amer. Acad. Arts, n. s. +
reddish-brown +
smooth +  and papillose +
1 +  and 2 +
well-developed +
yellow;reddish-brown +
flexuose +  and straight +
elongate +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
1/3 +  and 1/2 +
spherical +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
superficial +
Orthodicranum rhabdocarpum +
Dicranum rhabdocarpum +
Dicranum +
species +
deciduous +
lanceolate +
green +  and yellowish green or brownish +