Syntrichia amphidiacea (Müller Hal.) R. H. Zander
Family: Pottiaceae
Synonyms
Barbula amphidiacea Müller Hal.
Tortula amphidiacea (Müller Hal.) Brotherus
NatureServe Conservation Status
G3G5
Distribution
North America. U.S.A. (North Carolina, Tennessee, Virginia). Mexico. Central America. South America. Africa, Asia (Daniels et al. 2016, Mishler 2007).
Habitat
In mixed hardwood forests and wooded lawns of human habitation in mountainous terrain. Occurring on acidic and basic rocks and on mortar of stonework, on bark of standing hardwoods, rarely on logs or soil. Regionally, moderate elevations (1800-4300 ft).
Brief Description and Tips for Identification
The following was compiled from Crum and Anderson (1981) and Mishler (2007).
Loosely tufted on rock or bark, stems erect, 2 -15 (-25) mm tall. Dry plants green to brown; new growth green when moist. Leaves keeled, incurved, twisted, and only slightly contorted when dry, flat and wide-spreading when moist, narrowly or broadly spatulate. Leaves costate, costa ending a few cells before the apex or percurrent (extending to the apex), costa smooth at back. Leaf laminal cells pluripapillose. Leaf margins revolute in lower ½ - ¾, entire. Cylindrical propagula common on adaxial and especially abaxial leaf surfaces.
Dioicous. Sporophytes unknown in the Southern Appalachians.
Regionally, Syntrichia amphidiacea is similar to Syntrichia ammonsiana and Syntrichia papillosa, yet distinctions between these are obvious once characters are understood. S. ammonsiana stands apart in its leaflike propagula and leaf margins that are plane, not revolute. S. papillosa bears spherical to ovoid propagula on the adaxial surface of the costa, leaf cells are unipapillose on the lower surface, and leaves end in an awn.
Salient Features
- Propagula cylindrical, borne on the abaxial and adaxial leaf surfaces
- Leaf margins revolute in lower portion of leaf
- Costa ending a few cells before the leaf apex, or costa percurrent
- Costa smooth at back
- Leaves spatulate
References
Crum, H. A., and L. E. Anderson (1981). Mosses of Eastern North America (Vol. 1). Columbia University Press
Daniels, A. E. D., Sreebha, R., and Kariyappa, K. C. 2016. Syntrichia amphidiacea (Pottiaceae)—new to India from the Western Ghats. Lindbergia, 39, 35-38.
Mishler, B.D. 2007. Syntrichia. In: Flora of North America, North of Mexico 27: 618-627.
Habitat
Syntrichia amphidiacea
While searching unsuccessfully for S. ammonsiana, S. amphidiacea was discovered. Lab verification was required for proper identification.
Syntrichia amphidiacea
This outcrop has scattered patches of S. amphidiacea.
Syntrichia amphidiacea
Closeup of previous outcrop with a green leaf used to point to a line of tufted plants of S. amphidiacea.
Habit
Syntrichia amphidiacea
Several dark tufts of S. amphidiacea are indicated.
Syntrichia amphidiacea
An outcrop supporting small tufts of S. amphidiacea (invisible at this scale where other mosses dominate).
Syntrichia amphidiacea
Yellow arrows indicate tufts of S. amphidiacea growing in bark crevices of a roadside black locust tree at Winding Stair Gap, SW of Franklin, NC.
Habit
Syntrichia amphidiacea
The numerous, globular and cylindrical speckles over the leaf surfaces are immature and mature propagula, respectively. Hydrated plants at right.
Syntrichia amphidiacea
Enlarge the image and note the labels in yellow indicating propagula borne on abaxial and adaxial leaf surfaces.
Syntrichia amphidiacea
The back of the costa is prominent in dried plants.
Habit
Syntrichia amphidiacea
While their size ranges overlap, S. amphidiacea is generally larger than S. ammonsiana with which it may co-occur on rock.
Morphology
Syntrichia amphidiacea
Arrows indicate revolute leaf margins.
Syntrichia amphidiacea
The costa is smooth at back.
Syntrichia amphidiacea
The costa ends a few cells before the leaf apex or extends to the leaf apex, not beyond. The circular areas are points of propagula production.
Morphology
Syntrichia amphidiacea
Arrows point to propagula in formation; mature propagula (2) in the insets at right.
Syntrichia amphidiacea
Leaf laminal cells are pluripapillose. Arrows indicate individual papillae of one cell.
Similar Taxon
Syntrichia ammonsiana
Given that S. ammonsiana may co-occur on the same rock with S. amphidiacea, the above image compares the two as they may be seen in the dried state with a hand lens in the field.