Cratoneuron filicinum
Cratoneuron
cratoneuron moss, fern-leaf hook-moss, fern-leaf rigid moss
cratoneuron moss
leaves gradually or suddenly narrowed to apex, plane or slightly concave;
alar cells usually many, region large, usually strongly widened marginally, reaching from margin to costa or almost so;
medial laminal cells 12–55 × 4–11 µm.
leaves not recurved or squarrose, straight or falcate, narrowly to broadly triangular or rounded-triangular, sometimes ovate, not plicate, longer than 1 mm;
base decurrent;
margins plane or near base slightly recurved, denticulate or serrulate almost throughout, limbidia absent;
apex acuminate, acumen plane or furrowed;
costa strong, single, usually percurrent or excurrent, sometimes ending well before apex;
alar cells differentiated, strongly inflated, hyaline, region well defined, transversely triangular;
medial laminal cells elongate-hexagonal, short-rectangular, rectangular, short-linear, or rarely linear, smooth;
marginal cells 1-stratose.
usually narrower, more strongly falcate.
dioicous.
horizontal, cylindric, curved;
peristome perfect;
exostome margins slightly dentate distally;
endostome cilia 2 or 3, well developed, nodose.
14–21(–25) µm.
with inner leaves gradually or suddenly narrowed to apex, plicate, margins denticulate or strongly so distally, apex acuminate, laminal cells smooth.
Cratoneuron filicinum
Cratoneuron
Strikingly rigid plants of Cratoneuron filicinum with extremely strong, often long-excurrent costae are sometimes found in streams or under heavily dripping water; these were sometimes recognized as Amblystegium tenax var. spinifolium in North America. Such plants have narrowly triangular or narrowly ovate-triangular leaves gradually narrowed to an acuminate or often obtuse point. Ordinary C. filicinum leaves are sometimes found in parts of such plants, or shoots on old plants of this kind may have a normal C. filicinum appearance. Molecular studies show that such plants likely represent habitat modifications and should therefore not be recognized taxonomically (L. Hedenäs 2011, 2012). Cratoneuron curvicaule (Juratzka) G. Roth was attributed to North America by H. A. Crum et al. (1973) as C. filicinum var. curvicaule (Juratzka) Mönkemeyer; the species has been considered a synonym of C. filicinum on several American web pages. However, as shown by Hedenäs (2003, 2011), this is a distinct species that differs both morphologically and molecularly from C. filicinum. The occurrence of C. curvicaule in North America has not been confirmed, and the only North American specimens referred to this species (H. G. Simmons 584 [in part] and 585, S) belong to C. filicinum.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Species 2 (1 in the flora).
Cratoneuron grows in slightly or strongly calcareous habitats that are at least periodically wet; plants have a strong leaf costa, relatively short, smooth laminal cells, and mostly lanceolate and leaflike paraphyllia. The differences between Cratoneuron and 2. Palustriella are described under the latter.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC - Local Web sites:
CalFlora, CalPhotos, 
Flora NW, 
IL Wildflowers, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
