Richard H. Zander
Hennedia R. Br. bis [illegitimate homonym]
Plants growing in loose turf or cushions, green above, reddish brown below. Stems ca. 0.5--1 cm; hyalodermis absent or weakly developed, not collapsed, sclerodermis absent or substereid, central strand present; axillary hairs of ca. 5 cells, proximal 1--2 cells occasionally somewhat thick-walled. Stem leaves appressed or incurved when dry, spreading when moist; ovate to long-lanceolate, occasionally ligulate or spathulate, adaxial surface plane or broadly channeled across leaf, (1.5--)3--4(--7) mm; base not differentiated in shape or ovate and somewhat sheathing, proximal margins commonly bordered; distal margins plane, dentate above or less commonly entire, bordered (sometimes intramarginally) by short-rectangular to elongate cells, usually less papillose, occasionally thick-walled, rarely 2--3-stratose; apex acute or rarely obtuse; costa percurrent or short-excurrent as flat, denticulate mucro, rarely ending 3--4 cells below apes, adaxial cells quadrate to short-rectangular, in 4--5 rows; transverse section round to elliptic, adaxial epidermis present, adaxial stereid band absent, guide cells 2--4 per layer in (1-)2 layers, hydroid strand present, usually large, abaxial stereid band present, of substereid cells, elliptic or round in section, abaxial epidermis present (occasionally only lateral) or absent; proximal cells differentiated across leaf, rectangular, 18--30 µm wide, (2--)4--6:1, walls of proximal cells thin; distal medial cells relatively large, quadrate to hexagonal or short-rectangular, ca. 18--24 µm wide, 1--2:1, often marginally elongate and multistratose; papillae hollow, simple to 2-fid, usually 6--8 or more per lumen, cell walls thin to evenly thickened, flat to weakly convex. Specialized asexual reproduction absent. Sexual condition autoicous, cladautoicous or dioicous. Perichaetia terminal, leaves somewhat larger than the cauline leaves. Seta 0.05--2.5 cm. Capsule stegocarpous, theca ovate to cylindric, occasionally microstomous, 0.8--3.5 mm, annulus of 2--4 rows of vesiculose cells; operculum conic to rostrate, often narrowly so, occasionally systilious; peristome teeth absent, rudimentary or of 32 long, filamentous teeth, twisted counterclockwise, teeth when well developed to 1.5 mm. Calyptra cucullate, occasionally flaring below and not split. Spores 8--30 µm. KOH distal laminal color reaction red.
Species 20 (2 in the flora): soil and rock, commonly in wet areas, nearly worldwide, most diverse in austral temperate areas.
This genus was recently recognized as much larger than previously thought (T. L. Blockeel 1991; R. H. Zander 1989, 1993). The bordered, dentate, plane leaves with flat laminal cells, red in KOH, are distinctive. The sporophyte varies among the species from well developed to much reduced. The operculum is often long, (0.6--)1.2--1.8 mm.
Blockeel, T. L. 1991. The genus Hennediella Par.: a note on the affinities of Tortula brevis Whitehouse & Newton and T. stanfordensis W. C. Steere. J. Bryol.16: 187--192. Zander, R. H. 1989. Seven new genera in Pottiaceae (Musci) and a lectotype for Syntrichia. Phytologia 65: 424--436. Zander, R. H. 1993. Genera of the Pottiaceae: Mosses of Harsh Environments. Bull. Buffalo Soc. Nat. Sci. 32.
Long, D. G.1979. A reassessment of the systematic position of Tortula stanfordensis Steere and T. khartoumensis. J. Bryol.10: 377--381.
Flowers, S.1973. Mosses: Utah & the West. Brigham Young Univ. Press, Provo, Utah.
Smith, A. J. E. and H. L. K. Whitehouse.1974. The sporophyte and male plants of Tortula stanfordensis and the taxonomic position of this and T. khartoumensis Pettet and T. rhizophylla (Sakurai) Z. Iwatsuki & K. Saito. J. Bryol.8: 9--14.
Steere, W. C.1951. Tortula stanfordensis, a new species from California. Bryologist 54: 119--123.
Wareham, R. T. 1939. Pottia. In A. J. Grout, Moss Flora of North America North of Mexico.1(4): 197--208.
Whitehouse, H. L. K. 1975. How fast is Tortula stanfordensis spreading in Britain? Bull. Brit. Bryol. Soc.26: 23--24.