Grimmia hamulosa


Mem. Calif. Acad. Sci. 1: 14. 1868,.

Synonyms: Grimmia brevirostris R. S. Williams
Treatment appears in FNA Volume 27. Treatment on page 243. Mentioned on page 228, 244, 544.

Plants in flat patches, blackish green. Stems 1–1.5 cm. Leaves homomallous-falcate, oblong-lanceolate, from a clasping base tapering to a long, subulate uncinate point, 2–3.5 mm, margins plane, erect distally, intermarginal bands absent, usually muticous, occasionally short hyaline awns present, not decurrent, costa narrow proximally; basal juxtacostal laminal cells short-rectangular, straight to sinuose, thick-walled; basal marginal laminal cells quadrate to short-rectangular, thick-walled; medial laminal cells irregularly rounded to quadrate, sinuose, thick-walled; distal laminal cells 2-stratose, irregularly rounded to quadrate. Perichaetial leaves not enlarged. Seta straight, 2.5–3.5 mm. Capsule occasionally present, exserted, oblate, shiny, smooth, becoming striate when dry, stomata absent, annulus absent, operculum conical, peristome split in distal half, basal segments smooth, distal segments papillose. Calyptra unknown.

Habitat: Dry granitic rock and boulders
Elevation: moderate to high elevations (1500-3500 m)


Of conservation concern.

Few collections of Grimmia hamulosa exist, its habitat is not well defined, and it is a somewhat confusing species. The original description is incomplete and partly incorrect, e.g. it lacks discussion and comparison with related taxa, and the seta is straight, not bent, as stated in the protologue. The species is characterized by: (1) a glossy habit with long tapering, homomallous, muticous leaves with plane margins; (2) a broad, weakly outlined costa that fills the distal part of the 2-stratose lamina; and (3) a glossy exserted capsule that lacks an annulus. Despite its unique leaf characters and lack of an annulus, Hastings has put it in subg. Litoneuron based on its thick, concave leaves with plane margins, costa not projecting prominently from the lamina, and exserted capsule on a straight seta. In 1999, Greven found G. hamulosa richly fruiting in Yosemite National Park. Although isotypes studied by Greven have muticous leaves, in some of the plants from Yosemite the leaves have inconspicuous short awns. However, these plants do not deviate in other aspects from the type specimen. Small specimens of this species resemble G. fragilis Schimper, a form of G. montana described from southern Europe. These plants are characterized by long, glossy leaves usually with broken tips. In G. hamulosa, the leaf tips are also frequently broken; however, in G. montana the costa is clearly defined, and the distal leaf margins are incurved.

Selected References


Lower Taxa

... more about "Grimmia hamulosa"
deciduous +  and persistent +
well-defined +
differentiated +
Roxanne I. Hastings +  and Henk C. Greven +
Lesquereux +
only rarely longer +
not papillose +
not decurrent +
sinuous +  and straight to sometimes +
sinuose-nodulose;quadrate;elongate +
oblate;elongate +
tapering +
undifferentiated +
plicate +  and smooth +
less +  and 1/2 +
not papillose +
mitrate +  and cucullate +
small;medium +
sulcate +  and smooth +
pendent +  and erect +
striate +  and smooth +
thin +  and thick +
thick-walled +  and thin-walled +
quadrate +  and rectangular +
excurrent;percurrent;excurrent +
subpercurrent +
reniform +, elliptical +  and terete +
usually not markedly larger +
Calif. +, Oreg. +  and Wash. +
moderate to high elevations (1500-3500 m) +
reproduction +  and asexual +
dioicous +  and sexual +
Dry granitic rock and boulders +
papillose +, mammillose +  and smooth +
thick-walled +  and sinuose +
specialized +
dioicous +, autoicous +  and sexual +
oblong-lanceolate +  and homomallous-falcate +
1;multistratose +
thick-walled +  and sinuose +
irregularly rounded +  and quadrate +
thick-walled +  and sinuose +
thick-walled +  and sinuose +
not +  and differentiated +
lanceolate;linear +
uncinate +  and subulate +
0.2 cm2 mm <br />0.002 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Mem. Calif. Acad. Sci. +
straight +
sigmoid +  and arcuate +
papillose +  and smooth +
short to long +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
ornamented +  and smooth +
globose +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
muticous;long-awned +
Grimmia brevirostris +
Grimmia hamulosa +
Grimmia subg. Litoneuron +
species +