31. CROSSIDIUM Juratzka, Laubm.-Fl

Crossidium · POTTIACEAE 611

GYMNOSTOMIELLA ° CROSSIDIUM

31. CROSSIDIUM Juratzka, Laubm.-Fl. Oesterr.-Ung., 127. 1882, name conserved · [Greek krossos, fringe or tassel, and -idion, diminutive, alluding to tassel-like fringe on adaxial surface of costa]

Claudio Delgadillo M.

Plants in thin turfs or small cushions. Stem 1–10 mm, central strand present. Leaves evenly distributed or crowded, imbricate to slightly twisted when dry, lingulate, lanceolate to deltoid, 0.5–2.0 mm, 1-stratose, concave in distal half, base rectangular to ovate, margins entire, plane to recurved, apex obtuse, rounded or emarginate; costa excurrent as a whitish hair, in section hydroids present between the stereid and the guide cells, stereid band abaxial, filaments restricted to adaxial surface of costa, filament cells cylindric to subspheric, usually thin-walled, terminal cell cylindric to conic to subspheric, generally thin-walled, often papillose; cells of leaf base rectangular, firm-walled; medial and distal leaf cells quadrate to rectangular, firm-walled, sometimes thick-walled, smooth or with 1 to 8 papillae on either surface. Sexual condition dioicous or monoicous; perigonia budlike, leaves short and broad; perichaetia little or not differentiated. Seta 5–20 mm. Capsule cylindric to ovoid-cylindric, erect; annulus of 1–2 rows of vesiculose cells; operculum conic to rostrate, erect or inclined; peristome short and cribrose to long and twisted. Calyptra cucullate. Spores finely papillose, 9–22 µm. Species 11 (4 in the flora): North America, Mexico, South America, s Europe, n, s Africa, Pacific Islands (New Zealand), Australia. 612 POTTIACEAE · Crossidium Crossidium rosei R. S. Williams, described from Peru, was reported from North America by T. T. McIntosh (1989) from a specimen collected in British Columbia. This is a small sample containing plants of at least three pottiaceous species, including a fertile plant of Pterygoneurum. The type from Peru shows no relationship to the Canadian plants; i.e., Crossidium rosei is not part of the North American flora. Application of the name C. davidai Catcheside by M. J. Cano et al. (1992, 1993) to the Canadian specimen does not account for the lingulate and piliferous leaves of the American material.

SELECTED REFERENCES Delgadillo M., C. 1973. A new species, nomenclatural changes, and generic limits in Aloina, Aloinella, and Crossidium. Bryologist 76: 271–277. Delgadillo M., C. 1975. Taxonomic revision of Aloina, Aloinella and Crossidium (Musci). Bryologist 78: 245–303. Cano, M. J., J. Guerra and R. M. Ros. 1993. A revision of the moss genus Crossidium (Pottiaceae) with the description of the new genus Microcrossidium. Pl. Syst. Evol. 188: 213–235.

1. Terminal cell of filaments subspheric, leaf cells papillose. 2. Cells of distal leaf smooth or with 1(–2) papilla on either exposed surface . . . . . 1. Crossidium aberrans 2. Cells of distal and mid-leaf pluripapillose ...... 2. Crossidium seriatum 1. Terminal cell of filaments cylindric or conic, leaf cells usually smooth. 3. Leaves lanceolate to lingulate-ovate; filament cells thin-walled; cells of distal leaf with firm walls; dioicous or cladautoicous ...... 3. Crossidium crassinervium 3. Leaves broadly deltoid to oblong-ovate; filament cells thick-walled; cells of distal leaf thick-walled, with lumen nearly obliterated; gonioautoicous ...... 4. Crossidium squamiferum

1. Crossidium aberrans Holzinger & E. B. Bartram, 2. Crossidium seriatum H. A. Crum & Steere, SouthW. Bryologist 27: 4, plate 2. 1924 Naturalist 3: 117, figs. 1–7. 1959 Crossidium spatulifolium Holzinger Plants 1–1.5 mm. Leaves lingulate & E. B. Bartram to oblong-ovate, 0.6–1.3 mm, Plants 2–3.5 mm. Leaves margins revolute from near apex lingulate, lanceolate or ovate, 0.7– to near base, smooth-celled in the 5 1.4 mm, margins recurved from middle and base, apex round to slightly emarginate; costa 5 5 5 5 5 near apex to near base, apex 5

5 5 5 5 excurrent, with an abaxial 5 rounded or emarginate, piliferous; costa excurrent, with an abaxial epidermis, filaments of 2–6 cells, epidermis, filaments of 1–4 cells, cells subspheric, with several cells subspheric, with several papillae per cell, terminal papillae per cell, terminal cell subspheric; cells of leaf cell subspheric; cells of leaf base 13–51 µm, medial and base 24–66 µm, medial and distal cells 13–26 µm, with distal cells 11–20 µm, smooth, with 1–2 abaxial papillae several papillae on either side of distal and median cells. or on either side in distal cells. Sexual condition dioicous Sexual condition cladautoicous. Seta 9–13 mm. Capsule or cladautoicous. Seta 8–16 mm. Capsule urn ovoid- urn oblong-cylindric, 1.5–2.3 mm; operculum 0.7–1.1 cylindric, 1.3–2 mm; operculum 0.5–1 mm; peristome mm; peristome strongly twisted, 1015–1100 µm. Spores strongly twisted, 650–980 µm. Spores spheric, ovoid or spheric, finely papillose, 11–13 µm. oblong, finely papillose, 9–13 µm. Capsules mature Jan–Jul. Sandy soil or rocks, along Capsule mature Jan–Jun(–Aug). Soil and rocks under dry washes, in open or shaded places in deserts; moderate shrubs, shaded banks or in open sites in dry washes; elevations (400–600 m); B.C.; Ariz., Calif., Nev., N.Mex.; moderate elevations (600–1500 m); Ariz., Calif., Colo., Mexico (Baja California); Europe (France, Spain, Nev., N.Mex., Tex., Utah; Mexico (Baja California, Switzerland). Sonora); n Africa. The leaf cells with several papillae on either free surface Crossidium aberrans is easily distinguished by the distinguish Crossidium seriatum from C. aberrans. A smooth or 1-papillose cells of the distal leaf blade and by poorly preserved specimen from Kansas is perhaps a the low filaments with subglobose-papillose terminal cells. juvenile form with awned leaves and reduced filaments. Crossidium · POTTIACEAE 613

3. Crossidium crassinervium (De Notaris) Juratzka, filaments of 4–10 cells, cells cylindric to subspheric, Laubm.-Fl. Oesterr.-Ung., 128. 1882 [thick-walled, terminal cell rectangular, subspheric or Tortula crassinervia De Notaris, Mem. Reale Accad. Sci. conic with 2–5 solid papillae; cells of leaf base 11–70 Torino 40: 303. 1838 µm, medial and distal cells 9–33 µm, smooth, thick- walled. Sexual condition gonioautoicous. Seta 5–20 mm. Varieties 2 (1 in the flora): North America, Europe, Capsule urn short-cylindric to ovoid-cylindric, 1–2.7 mm; n Africa, Asia (China, India), Atlantic Islands (Canary operculum 0.6–1.1 mm; peristome short, nearly straight, Islands). cribose at base to long and strongly twisted, 198–1160 µm. Spores spheric, 9–22 µm. Varieties 2 (2 in the flora): North America, nw Mexico, 3a. Crossidium crassinervium (De Notaris) Juratzka) Europe, Asia (India), n Africa, Atlantic Islands (Canary var. crassinervium Islands). Crossidium desertorum Holzinger & Crossidium squamiferum is a distinctive species E. B. Bartram; C. erosum Holzinger characterized by a whitish marginal area on the distal & E. B. Bartram half of the leaves, thick-walled distal leaf cells, a long Plants 1–5 mm. Leaves lanceolate, hyaline hair point, thick-walled filaments ending in a lingulate to lingulate-ovate, 0.5– papillose terminal cell, and the gonioautoicous sexual 1.3 mm, margins recurved to condition. North American specimens without 5

5 5 sporophytes from Arizona, California, Colorado, and

5 revolute from near apex to near base, apex obtuse, rounded or Utah have been studied, but these cannot be satisfactorily emarginate, piliferous; costa referred to an infraspecific category. The type specimen excurrent, with an abaxial epidermis, filaments 2–12 cells, of C. succulentum is also sterile. cells cylindric, thin-walled, with 2–4 hollow papillae on 1. Capsule ovoid-cylindric with a long and twisted apical cell, terminal cell cylindric or conic; cells of leaf peristome; operculum long-rostrate ...... base 7–58 µm, medial and distal cells 7–22 µm, smooth...... 4a. Crossidium squamiferum var. squamiferum Sexual condition dioicous or cladautoicous. Seta 6–13 1. Capsule cylindric with a short, cribrose peristome; mm. Capsule urn ovoid-cylindric, 0.9–2.2 mm; operculum conic ...... operculum 0.6–1 mm; peristome strongly twisted, 400– ...... 4b. Crossidium squamiferum var. pottioideum 900 µm. Spores spheric, nearly smooth to conspicuously papillose, 9–15 µm. 4a. Crossidium squamiferum (Viviani) Juratzka var. Capsule mature Dec–Jul. Soil and rocks, on banks squamiferum and dry washes, under shrubs in desert areas; moderate Crossidium succulentum Holzinger to high elevations (500–1700 m); Ariz., N.Mex., Tex., & E. B. Bartram Utah; Mexico; Europe; Asia (China, India); n Africa; Leaves with margins recurved to Atlantic Islands (Canary Islands). erect distally, undifferentiated in Crossidium crassinervium is characterized by the North American plants. Seta 7– smooth-walled leaf cells and long, thin-walled filaments 20 mm, urn ovoid-cylindric, 1.7– 5 with cylindric to conic terminal cells. Papillae are present 5 2.7 mm; operculum 0.7–1.1 mm; on the apex of the terminal cell and, occasionally, on the peristome long, strongly twisted, distal leaf cells. sometimes cribrose at base, 250– 1160 µm. 4. Crossidium squamiferum (Viviani) Juratzka, Laubm.- Capsules mature (Aug–)Dec–Mar. Soil, sandy soil or Fl. Oesterr.-Ung., 127. 1882 (as squamigerum) rocks, dry washes; moderate elevations (800–1000 m); Barbula squamifera Viviani, Ann. Ariz., Calif.; Europe; Asia (India); n Africa; Atlantic Bot. (Genoa) 1(2): 191. 1804; Islands (Canary Islands). Tortula squamifera (Viviani) De North American specimens of var. squamiferum lack Notaris the differentiated border at the leaf base that is distinctive Plants 6–10 mm. Leaves deltoid- of the taxon elsewhere. Some specimens may show an indistinct proximal leaf border or a peristome somewhat 5 5 5 ovate, oblong-ovate or lanceolate, 5 5 0.6–2 mm, margins recurved to cribrose at base, indicating intergradation with var. erect distally, usually undiffer- pottioideum. Despite this, var. squamiferum is recognized entiated, apex obtuse or rounded, in North America by long setae, ovoid-cylindric capsules, serrulate, with abaxial papillae, piliferous; costa and a long and twisted peristome. excurrent, with an inconspicuous abaxial epidermis, 614 POTTIACEAE · Crossidium · Aloina

CROSSIDIUM ° ALOINA

4b. Crossidium squamiferum var. pottioideum Capsule mature May–Aug(–Dec). Banks, sandy soil (Notaris) Mönkemeyer, Laubm. Eur., 315. 1927 or rocks along dry washes; 1000–1500 m; Ariz., Calif., Tortula squamifera var. pottioidea Colo., Nev., Utah; Mexico (Baja California); Europe; De Notaris, Musci Ital., 22. 1862; Asia; n Africa; Atlantic Islands (Canary Islands). Crossidium griseum (Juratzka) M. J. Cano et al. (1993) did not recognize var. Juratzka pottioideum as a distinct taxon. However, the character states given in the key offer good reasons to retain it, Leaves with margins recurved to despite some intergradation with var. squamiferum.

5 5 5 erect and whitish distally, 5 5 undifferentiated proximally. Seta 5–8 mm. Capsule urn short- cylindric, 1–2.1 mm; operculum 0.6–1.1 mm; peristome short, nearly straight, cribrose, 198–520 µm.

32. ALOINA (Müller Hal.) Kindberg, Bih. Kongl. Svenska Venensk.-Akad. Handl. 6(19): 22. 1882, name conserved · [Genus Aloë and Latin -ina, resembling, alluding to fleshy leaves]

Claudio Delgadillo M.

Barbula sect. Aloina Müller Hal., Syn. 1: 596. 1849

Plants in thin turfs or scattered. Stem 0.5–6 mm, central strand present. Leaves forming a rosette, lingulate, suborbicular or deltoid, deeply concave, 0.5–2.8 mm, infolded, partly 2- stratose, base auriculate, sheathing, margins entire to irregularly crenulate distally, apex cucullate, Aloina · POTTIACEAE 615 mucronate or piliferous; costa broad, percurrent to long-excurrent, in section hydroids absent, stereid band abaxial, occasionally wanting, filaments present on costa and adjacent 2-stratose area of leaf blade, filament cells cylindrical to subspheric, thin-walled, terminal cell subspheric to nearly conic, with an apical thickening; cells of leaf base thin-walled, rectangular, sometimes differentiated marginally, medial and distal leaf cells thick-walled, mostly transversely elongated, smooth. Sexual condition monoicous or dioicous, perigonia distinct, with noncucullate unfolded leaves, perichaetia sometimes partly differentiated, the inner leaves with unfolded blades. Seta 4.5–17 mm. Capsule cylindric to ovoid-cylindric, erect or slightly inclined, annulus of 1–2 rows of vesiculose cells, deciduous or persistent, operculum conic to long-rostrate, erect or inclined, peristome generally long and twisted, papillose, with a basal membrane. Calyptra cucullate. Spores spheric, finely papillose, 9–25 µm. Species 9 (5 in the flora): North America, Mexico, Central America, South America, Mediterranean Basin, s Africa, Pacific Islands (New Zealand), Australia. Aloina is sparsely distributed in the New World. It is generally a very distinct genus characterized by differentiated leaf bases, infolded partly 2-stratose laminae, broad costae, and filaments ending in a terminal cell with an apical thickening; the filaments cover the costa and part of the lamina. Plants of Aloina sometimes resemble Indusiella (Grimmiaceae) in habit and general leaf structure although no filaments are found on the leaves of the latter.

1. Leaf apex piliferous; costa undifferentiated in the distal two thirds, in section with no stereid band, but with a few stereid or substereid cells in mid-costal region ...... 1. Aloina bifrons 1. Leaf apex muticous; costa percurrent to subpercurrent, in section with 1–7 stereid layers. 2. Leaf base without a differentiated margin of thin-walled hyaline cells. 3. Costa with strong solid papillae on the abaxial side at and near the apex; capsule ovoid-cylindric, peristome short (to 900 µm), nearly straight ...... 2. Aloina hamulus 3. Costa smooth abaxially; capsule cylindric, peristome long (600–1200 µm) and twisted ...... 3. Aloina aloides 2. Leaf base with a marginal area of narrow thin-walled hyaline cells. 4. Leaves suborbicular to short-lingulate; synoicous (or dioicous); capsule cylindric, operculum conic to short-rostrate ...... 4. Aloina brevirostris 4. Leaves ligulate; dioicous; capsule ovoid-cylindrical, operculum long-rostrate ...... 5. Aloina rigida

1. Aloina bifrons (De Notaris) Delgadillo, Bryologist 76: Sexual condition dioicous. Seta 6–14 mm. Capsule urn 273. 1973 cylindric to ovoid cylindric, 1.7–3.2 mm; operculum Tortula bifrons De Notaris, Mem. conical, rostrate, erect or slightly inclined, 0.9–1.4 mm; Reale Accad. Sci. Torino 40: 305. peristome 800–1230 µm, strongly twisted; spores 9–24 1838; Aloina pilifera (De Notaris) µm. H. A. Crum & Steere; A. rigida var. Capsules mature Jan–Jul(–Aug). Sunny sandy soil or pilifera (De Notaris) Limpricht soil over limestone in dry areas; moderate elevations (300–800 m); Ariz., Calif., Idaho; Mexico (Baja 5 5 Plants to 3 mm. Leaves lingulate California, San Luis Potosí, Nuevo León, Puebla and 5 to ovate-lingulate, 1–2.5 mm, Zacatecas); s South America; s Europe; sw Asia (Jordan); margins entire to serrulate, Africa (Egypt, South Africa); Pacific Islands (New undifferentiated at base, apex Zealand); Australia. piliferous, open, broadly obtuse or rounded; costa Aloina bifrons is readily identified by the hyaline hair undifferentiated, with few or no stereid cells, filaments of the leaf apex and the poorly developed costa that is of 4–8 cells, cells subspheric to cylindric; cells of leaf base only evident toward the leaf base, but inconspicuous in 18–37 µm, medial and distal cells 9–22 µm, papillae none. the distal half of the leaf. No other North American species of the genus exhibits a piliferous leaf apex. 616 POTTIACEAE · Aloina

2. Aloina hamulus (Müller Hal.) Brotherus in H. G. A. 3a. Aloina aloides var. ambigua (Bruch & Schimper) Engler and K. Prantl, Nat. Pflanzenfam. 214[I,3]: 428. E. J. Craig in A. J. Grout, Moss Fl. N. Amer. 1: 214. 1902 1939 Barbula hamulus Müller Hal., Bull. Barbula ambigua Bruch & Schimper, Herb. Boissier 5: 192. 1897 Bryol. Europ. 2: 76, plate 139. 1842

5 Plants to 6 mm. Leaves lingulate, 5 Plants to 2.5 mm. Leaves ligulate 0.6–2 mm, margins entire to to lingulate, 1–2.8 mm, margins 5 5

5 irregularly crenulate, undifferen- 5 5 entire, undifferentiated at base, 5

5 5 5 5 tiated at base, apex cucullate; 5 apex cucullate to nearly open; 5 5 5 5

5 5 5 5 costa subpercurrent to percurrent, 5 costa subpercurrent to percurrent, filaments of 3–7 cells, cells filaments of 3–6 cells, cells cylindric to subspheric; cells of leaf subspheric; cells of leaf base 15– base 13–59 µm, medial and distal cells 9–26 µm, large 64 µm, medial and distal cells 11–24 µm, occasionally solid papillae on abaxial surface distally. Sexual condition with large solid papillae at leaf tip. Sexual condition dioicous. Seta 7–16 mm. Capsule urn ovoid-cylindric, dioicous or rhizoautoicous. Seta 5.5–12.5 mm. Capsule 1.1–3 mm; operculum conical to long rostrate, erect or urn cylindric, 1.5–3 mm; operculum campanulate, 1–1.4 inclined, 0.5–1.2 mm; peristome to 900 µm, twisted to mm; peristome 600–1200 µm, strongly twisted. Spores nearly straight. Spores 9–13 µm. 13–24 µm. Sporophytes unknown in flora area. Sandstone or Capsules mature Jan–May. Low, desert areas, banks calcareous rocks, sandy soil in dry sunny sites; moderate and dry washes, soil and limestone; moderate elevations to high elevations (700–1800 m); Colo., Ill., Kans., La., (400–800 m); Ariz., Calif.; Mexico (Baja California); Nebr., Okla., Tex.; Mexico; Central America (El Salvador, Europe; Asia (India, Israel, Jordan, Lebanon, Turkey); Guatemala). n Africa; Australia. The undifferentiated marginal cells of the leaf base In var. ambigua, the cylindric capsules with a long and and the large abaxial solid papillae near the leaf tip twisted peristome are distinctive. Forms with short- distinguish Aloina hamulus from A. rigida, which, in lingulate leaves may be confused with Aloina hamulus addition, has a strongly twisted and longer peristome. when sterile. Outside North America, var. ambigua may The ovoid-cylindric capsule and abaxially papillose leaves occur as high as 2100 m. distinguish this species from A. aloides var. ambigua. Young leaves should be checked when papillae are not 4. Aloina brevirostris (Hooker & Greville) Kindberg, evident in mature leaves. Bih. Kongl. Svenska Vetensk.-Akad. Handl. 7(9): 137. 1883 3. Aloina aloides (Schultz) Kindberg, Bih. Kongl. Svensk. Tortula brevirostris Hooker & Vetensk.-Akad. Handl. 7: 136. 1883 5 Greville, Edinburgh J. Sci. 1: 289, Trichostomum aloides Schultz, Nova Acta Phys.-Med. Acad. 5 plate 12. 1824 5 5 5 Caes. Leop.-Carol. Nat. Cur. 11: 197. 1823; Barbula aloides Plants 0.5–2 mm. Leaves lingulate 5 5 (Schultz) Bruch; Tortula aloides (Schultz) De Notaris 5 5 to suborbicular, 0.5–1.5 mm, 5 Varieties 2 (1 in the flora): sw United States, Mexico, margins entire, undulate-dentic- Europe, n Africa, Asia, Atlantic Islands (Canary Islands), ulate distally, differentiated at Australia. base, apex cucullate to nearly open; costa subpercurrent, filaments of 2–5 cells, cells subspheric to cylindric; cells of leaf base 13–66 µm, medial and distal cells 13–40 µm, papillae none. Sexual condition synoicous or dioicous. Seta 6–17 mm. Capsule urn cylindric, 1–2 mm; operculum conic, short-rostrate, erect or inclined, 0.5–1 mm; peristome 250–900 µm, twisted. Spores 15–25 µm. Capsules mature (Mar–)May–Aug. Bare or disturbed soil or silt, roadside banks, calcareous boulders or gravel; low to moderate elevations (100–1500 m); Greenland; Alta., B.C., Man., N.W.T., Nunavut, Ont., Yukon; Alaska, Mont.; Europe; Asia (Siberia). Aloina · POTTIACEAE 617

ALOINA ° SYNTRICHIA

The leaves of Aloina brevirostris are usually short, and 5a. Aloina rigida (Hedwig) Limpricht var. rigida cucullate with a reduced lamina; forms with larger Plants to 2.5 mm. Leaves short- laminae may be confused with A. rigida, but the synoicous lingulate to ligulate, 0.5–2.5 mm, condition and the cylindric capsules with a conical margins entire to irregularly 5 5 operculum are diagnostic. The latter species is dioicous, denticulate, differentiated at base,

5 and has ovoid-cylindrical capsules with a long-rostrate 5 5 apex cucullate; costa subpercur- 5 5 operculum. 5 rent to percurrent, filaments of 3– 5 5 5 5 5 5 9 cells, cells cylindric to spheric; 5 5. Aloina rigida (Hedwig) Limpricht, Laubm. Deutschl. cells of leaf base 11–88 µm, medial 1: 637. 1888 and distal cells 9–40 µm, papillae Barbula rigida Hedwig, Sp. Musc. Frond., 115. 1801 none. Sexual condition dioicous. Seta 4.5–17 mm. Varieties 3 (1 in the flora): North America, Mexico, South Capsule urn ovoid-cylindric, 1.7–3.4 mm; operculum America, Europe, Asia, Africa. conical to subulate, long-rostrate, 1.2–1.9 mm; peristome 1200–1750 µm, strongly twisted. Spores 11–22 µm. Capsules mature Jun–Aug(–Oct). Rocks, banks, clay, sandy or gravelly soil in deserts, plains or conifer forests; moderate to high elevations (1000–3000 m); Alta., B.C., N.B., N.S., Nunavut, Ont., Yukon; Colo., Ill., Iowa, Kans., Mont., Nebr., N.Mex., Tex.; Mexico (Nuevo León, Querétaro, Zacatecas); South America; Europe; Asia; Africa. The ovoid-cylindrical capsule with a long peristome and long-rostrate operculum as well as the differentiated basal leaf margins are the distinguishing features of var. rigida. Despite recent reports from California, this species has not been confirmed from that state. 618 POTTIACEAE · Syntrichia 33. SYNTRICHIA Bridel, J. Bot. (Schrader) 1801(1): 299. 1801 · [Greek syn, plus, and trichos, hair, alluding to twisted peristome united by a basal membrane]

Brent D. Mishler

Plants small to large tufts, green to yellow- or red-brown. Stems simple or forked, epidermal cells differentiated in 1–3 layers, central strand usually present. Leaves appressed and variously twisted when dry, erect-spreading to squarrose when moist, obovate, spatulate, or lingulate, rarely broadly oblong-lanceolate; margins plane or revolute, usually entire; apices acute to truncate or emarginate, and often apiculate; costa generally strong, percurrent to long-excurrent as a hyaline or colored awn, usually rounded abaxailly, in section showing 1 median layer of large guide cells, 1–3 layers of smaller adaxial cells, a weak or strong abaxial stereid band, and sometimes a group of hydroids, but no abaxial epidermis of larger cells; basal cells abruptly differentiated, large and rectangular, smooth, hyaline, thin-walled, often lax; distal cells quadrate or sometimes slightly longer than wide, small and obscure to large and lax, usually pluripapillose on both surfaces, rarely 1-papillose only on the abaxial surface; marginal cells sometimes differentiated, thicker-walled and colored or pale. Specialized asexual reproduction often present, propagula borne on the lamina or costa, in leaf axils, or on rhizoids, in shape leaflike, spherical, or cylindric. Sexual condition dioicous, autoicous, or synoicous; perigonial bracts often short, ovate or oblong-lingulate, blunt, with costa often ending before the apex, perichaetia terminal, the bracts not differentiated. Seta red or brown, elongate, smooth. Capsule erect, straight or slightly curved, red or brown, cylindric, sometimes with a distinct neck, usually striolate when dry; operculum conic, straight or slightly oblique, shorter than the urn; peristome consisting of 32 filiform, reddish, papillose divisions slightly to strongly twisted together above a pale, tessellated basal membrane 1/6–2/3 the total length of the peristome. Calyptra long-cucullate, acute, yellow or brown. Spores finely to strongly papillose. KOH laminal color reaction brick- red. Species ca. 80 (17 in the flora): North America, Mexico, Central America, South America, Europe, Asia, Africa, Atlantic Islands, Pacific Islands (Hawaii, New Zealand), Australia, Antarctica. Syntrichia appears to be a monophyletic group, segregated from Tortula by synapomorphic leaf characters, in particular the large basal cells abruptly differentiated from the small distal cells, usually forming an inverted U-shaped group on each side of the costa. Also, the costal cross section of Syntrichia lacks an abaxial epidermis, unlike the case in Tortula. The high basal membrane of the peristome, while responsible for the name of the genus, is not diagnostic for Syntrichia since an equally high basal membrane has evolved in Tortula as well.

SELECTED REFERENCES Mishler, B. D. 1994. Tortula. In: A. J. Sharp et al., eds. The moss flora of Mexico. Mem. New York Bot. Gard. 69: 319–350. Steere, W. C. 1939c. Tortula. In: A. J. Grout. 1928–1940. Moss Flora of North America, North of Mexico. 3 vols. in 12 parts. Newfane, Vt. and New York. Vol. 1, pp. 228–246.

1. Costa percurrent or short-excurrent into a mucro or apiculus. 2. Laminal cells collenchymatous (sometimes weakly so; often best observed in the region where the basal and distal cells meet). 3. Leaves strongly bordered by thicker-walled, often colored cells; propagula present, cylindric ...... 1. Syntrichia amphidiacea 3. Leaves not bordered; propagula absent ...... 3. Syntrichia cainii 2. Laminal cells with evenly thickened walls, not collenchymatous. 4. Propagula present, leaflike, papillose, borne on stalks in leaf axils 5. Leaves 2-stratose ...... 7. Syntrichia chisosa 5. Leaves 1-stratose ...... 8. Syntrichia ammonsiana 4. Propagula absent or, if present, cylindric, smooth, borne on leaf surface. Syntrichia · POTTIACEAE 619

6. Leaves not fragile; propagula present ...... 4. Syntrichia latifolia 6. Leaves fragile, often broken and appearing eroded; propagula absent . . . . . 9. Syntrichia fragilis 1. Costa excurrent as an awn. 7. Laminal cells collenchymatous, with single papilla on abaxial surfaces ...... 2. Syntrichia papillosa 7. Laminal cells with evenly thickened walls, not collenchymatous, with multiple papillae on both surfaces. 8. Leaf margins plane or slightly recurved at mid leaf. 9. Plants sometimes bearing green, fusiform, axillary propagula; costa smooth abaxially; awn smooth or with a few short teeth ...... 5. Syntrichia laevipila 9. Plants without propagula; costa strongly papillose abaxially; awn serrulate ...... 6. Syntrichia bartramii 8. Leaf margins strongly revolute at least in proximal part of leaf. 10. Leaf 2-stratose or thicker ...... 14. Syntrichia caninervis 10. Leaf 1-stratose. 11. Costa lacking hydroids but having a row of large-lumined cells abaxial to guide cells; stem lacking a central strand; basal leaf cells 11–23 µm wide; leaves tapered to the apex from their widest point about one-third the way up from the base, without a constriction near mid leaf. 12. Distal cells with tall, bulging mammillae, 11–14 µm high, as high as the thickness of the lamina, sometimes higher, also bearing 1–2 papillae per cell ...... 15. Syntrichia papillosissima 12. Distal cells with mammillae much lower than thickness of the lamina. 13. Leaf margins plane in the distal 1/4; distal cells 13–18 µm ...... 16. Syntrichia norvegica 13. Leaf margins recurved nearly to the apex; distal cells 8–12 µm ...... 17. Syntrichia ruralis 11. Costa with hydroids; stem with a central strand; basal leaf cells 20–40 µm wide; leaves constricted near mid leaf. 14. Awns short, to 0.5 mm, smooth or with a few short teeth ...... 10. Syntrichia sinensis 14. Awns long, 0.5–3 mm, serrate. 15. Distal laminal cells 8–12 µm ...... 11. Syntrichia montana 15. Distal laminal cells 12–23 µm. 16. Leaf apex truncate, retuse, or emarginate; costa yellowish to brownish, not serrulate near the apex because of projecting cell ends; distal cells 15–23 µm; autoicous ...... 12. Syntrichia obtusissima 16. Leaves acute (or sometimes truncate); costa reddish and serrulate near the apex because of projecting cell ends; distal cells 12–17 µm; synoicous ...... 13. Syntrichia princeps

1. Syntrichia amphidiacea (Müller Hal.) R. H. Zander, smooth; basal cells abruptly differentiated, narrower Bull. Buffalo Soc. Nat. Sci. 32: 267. 1993 toward the margins; distal cells rounded, polygonal, or Barbula amphidiacea Müller Hal., quadrate, 11–14 µm (or slightly elongate and 13–22 µm), Linnaea 38: 639. 1874; Tortula with 3–6 low or high papillae per cell, thick-walled and amphidiacea (Müller Hal.) collenchymatous; marginal cells in several rows smaller Brotherus; T. caroliniana L. E. and smoother with thicker, often colored walls. Andrews Specialized asexual reproduction as gemmae on the adaxial or occasionally the abaxial leaf surface of leaves, Stems 2–15(–25) mm. Leaves 5 cylindric, rounded at the ends, up to 50 (rarely 200) µm, 5 5 infolded, twisted, and only slightly brown when mature, multicellular. Sexual condition contorted when dry, erect- dioicous. [Seta red, 6–8(–10) mm. Capsule red, 2–3 spreading when moist, variable in (–3.5) mm, straight or slightly curved, with a distinct shape and size, narrowly or broadly spatulate, (1.5–)2– neck; operculum 1–1.5 mm; peristome 0.5–1 mm, basal 3(–4) × 0.75–1.5 mm; margins revolute in the proximal membrane 1/6–1/5 the total length, teeth irregularly twisted 1 3 /2– /4, entire; apices acute to acuminate; costa ending a and contorted (crumpled) when dry, widely spreading or few cells before the apex or percurrent, yellow or brown, 620 POTTIACEAE · Syntrichia reflexed when moist, red. Spores 18–22 µm, strongly the costa distinguish S. papillosa, even with a hand lens. papillose.] Sporophytes are known only from Australia, Tasmania, Bark of trees, logs, acidic and basic rocks, occasionally and New Zealand. soil; low to high elevations (to 3000 m); N.C., Tenn., Va.; Mexico; Central America; n South America. 3. Syntrichia cainii (H. A. Crum & L. E. Anderson) The peristome of Syntrichia amphidiacea is unusual, R. H. Zander, Bull. Buffalo Soc. Nat. Sci. 32: 267. 1993 being irregularly twisted and crumpled when dry but widely spreading or reflexed when moist. The species Tortula cainii H. A. Crum & L. E. has a distribution disjunct between the southern Anderson, J. Elisha Mitchell Sci. Soc. Appalachians and Mexico, similar to that of a number 74: 35, figs. 10–17. 1958 of other mosses (including S. fragilis) and flowering plants that appear to be relicts of an ancient tropical flora. Stems 10–20 mm. Leaves Sporophytes are known only from southern Mexico and 5 infolded, twisted, and slightly southwards. Syntrichia amphidiacea is a rare species in contorted when dry, erect- the southeastern United States but common in Mexico. spreading with recurved tips when moist, variable in shape and size, 2. Syntrichia papillosa (Wilson) Juratska, Laubm.-Fl. usually oblong-ovate, 1.5–2 × 1 2 Oestrr.-Ung., 141. 1882 0.75–1.5 mm; margins revolute in the proximal /2– /3, entire; apices obtuse but abruptly narrowed to a blunt Tortula papillosa Wilson, London J. tip; costa ending well before the apex, brown, smooth; Bot. 4: 193. 1845 basal cells abruptly differentiated, narrower toward the Stems 1–4(–8) mm. Leaves margins; distal cells rounded, polygonal, or quadrate, 12– incurved and slightly twisted when 18 µm, with 3–5 papillae per cell, thick-walled and

5 5 5 dry, erect to wide-spreading when collenchymatous. Specialized asexual reproduction 5

5 5 5 5 5 5 5 5 5 moist, spatulate, (1.5–)2–3 × absent. Sexual condition dioicous (perigonia and 5 5 5 5 5 5 5 5 5 5 0.75–1.25 mm; margins incurved sporophytes unknown). when dry, plane to erect when Limestone; moderate elevations; Ont. moist, entire or occasionally Plants identified as Syntrichia cainii from elsewhere serrulate near the apex; apices acute; costa excurrent into in North America (e.g., Kansas, Colorado, and a short, smooth or serrulate, yellowish or hyaline awn California) are probably incorrectly identified. The 1/8–1/5 the leaf length, yellow or red, rounded and sharply difficulty comes from several other species (especially S. papillose-serrate abaxially, smooth on the adaxial surface; norvegica) having scattered neotenic races in which the basal cells gradually differentiated; distal cells mature leaves lack awns and thus appear superficially isodiametric, rounded-hexagonal, 14–22 µm, papillae similar to S. cainii. More detailed research, including abaxial, single, simple, rarely forked near the costa, cells culture studies, is needed to better understand and rather thick-walled, collenchymatous; cells elongate near distinguish these forms. leaf apex. Specialized asexual reproduction by gemmae borne on the adaxial surface of the costa, spherical or 4. Syntrichia latifolia (Bruch ex Hartman) Huebener, ovoid, 4–10-celled, brown when mature, smooth. Sexual Muscol. Germ., 342. 1833 condition reportedly dioicous. Sporophytes not known Tortula latifolia Bruch ex Hartman, from the flora region. Handb. Skand. Fl. ed. 2, 322. 1832 Bark of trees or in rock crevices; low to high elevations; N.S., Ont.; Ariz., Calif., Colo., Conn., Ga., Ill., Maine, Stems 4–12 mm. Leaves infolded, twisted, and slightly contorted Mass., Mich., Mo., Nev., N.J., N.Mex., N.Y., N.C., Ohio, 5

5 when dry, erect-spreading when

Pa., Tenn., Tex., Utah, Wash.; Mexico; South America 5 moist, narrowly or broadly (Brazil, Colombia, Ecuador); Europe; s Africa; Atlantic 5 5 Islands (Falkland Islands); Pacific Islands (New Zealand); spatulate, 1.8–2.8 × 0.6–0.8 mm; Australia. margins revolute in the proximal 1 The leaves of Syntrichia papillosa have unipapillose /2, entire; apices obtuse; costa cells, with the papillae only on the abaxial surface, ending a few cells before the apex or percurrent, brown, strongly papillose-serrate costae, and small, smooth, smooth; basal cells abruptly differentiated, narrower brown propagula borne on the adaxial surface of the toward the margins; distal cells rounded, polygonal, or costa. The plants superficially resemble S. laevipila in quadrate, 12–18 µm, with 4–6 papillae per cell. the field, but the position and nature of the propagula as Specialized asexual reproduction by gemmae on the well as the incurved leaf margins and roughened back of adaxial or occasionally the abaxial leaf surface of leaves, Syntrichia · POTTIACEAE 621 ovoid and rounded, 25–45 µm in diameter, green to complex of small, corticolous plants. These plants might brown, multicellular. Sexual condition dioicous. Seta be confused superfically with S. papillosa, but the leaf red, 6 mm. Capsule red, 3 mm, straight, with a distinct margins are plane, the abaxial surface of the costa is neck; operculum 1.5–2mm, red; peristome 1 mm, basal smooth and shiny, the propagula are leaf-like, and the membrane 1/2–2/3 the total length, red. Spores 10–15 µm, leaf cells are pluripapillose in S. laevipila. The other taxa papillose. with leaf-like propagula, S. chisosa and S. ammonsiana, Bark of trees, rarely on rocks; low to high elevations; are never corticolous. B.C.; Ariz., Calif., Oreg., Wash.; Europe. 6. Syntrichia bartramii (Steere) R. H. Zander, Bull. 5. Syntrichia laevipila Bridel, Muscol. Recent., suppl. 4: Buffalo Soc. Nat. Sci. 32: 267. 1993 98. 1818 Tortula bartramii Steere in A. J. Syntrichia pagorum (Milde) J. J. Grout, Moss Fl. N. Amer. 1: 241, Amann; Tortula laevipila var. plate 115, fig. B. 1939 meridionalis (Schimper) Wijk & Stems 2–10 mm. Leaves infolded Margadant; T. pagorum (Milde) De and spirally twisted around the 5 Notaris 5

5 5 stem when dry, wide-spreading 5 5 5 5 5 5 5 5 5 5 Stems 1–3(–5) mm. Leaves 5 when moist, lingulate to spatulate, 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 infolded and somewhat twisted 1.25–2 × 0.5–0.75 mm; margins when dry, erect-spreading when plane, entire, except for papillose moist, spatulate, 1–1.75 × 0.5– crenulations, not bordered; apices acute to truncate or 0.75 mm; margins plane (or somewhat erect), crenulate; occasionally emarginate; costa excurrent into a apices obtuse, blunt, or emarginate; costa excurrent into conspicuously tapered, serrate awn 0.1–0.6 mm, red or a conspicuously tapered, smooth, yellowish or hyaline yellow, sparsely to densely spinulose abaxially; basal cells awn 1/5–1/2 the length of the leaf, yellow or red, rounded abruptly differentiated, with somewhat thickened cross and smooth on abaxial surface; basal cells rather abruptly walls, those at the margins narrower; distal cells differentiated, often with thickened cross-walls, usually irregularly polygonal, isodiametric, 9–13 µm, obscure, extending slightly farther up the margin than near the bulging and densely papillose, with 4–6 papillae per cell, costa; distal cells quadrate to hexagonal, 10–15 µm, moderately thick-walled and not collenchymatous. bulging, with about 4 papillae per cell, the outermost Specialized asexual reproduction absent. Sexual row of cells less papillose. Specialized asexual condition dioicous (perigonia and sporophytes reproduction as propagula borne at the tip of the stem unknown). and in axils of distal leaves, fusiform, green, ecostate, Dry soil and rocks; moderate to high elevations; Ariz., papillose, with an elongate terminal cell, occasionally as Calif., Colo., Idaho, N.Mex., Tex.; Mexico (Baja several cells. Sexual condition dioicous or autoicous. Seta California). red, 5–15 mm. Capsule red, 3–5 mm, straight, with a Diagnostic features of the rare Syntrichia bartramii distinct neck; operculum 1–2 mm, red; peristome 0.5–1 include plane leaf margins and the costa excurrent into a mm, basal membrane 1/2 the total length, red. Spores tapered, serrate awn. In contrast with those of S. fragilis, 10–16 µm, papillose. the leaves of S. bartramii are not fragile and have awns, Occasional on bark of trees, rarely on rock; low to somewhat smaller, more obscure distal cells, less well- high elevations; B.C.; Ala., Ariz., Ark., Calif., Colo., defined groups of basal cells, and plane margins. Without Conn., Ga., Kans., Ky., La., Md., Mo., Nebr., Nev., propagula, plants of S. laevipila can be separated from N.Mex., N.C., Ohio, Okla., Oreg., S.C., S.Dak., Tenn., S. bartramii by the abaxially smooth costae and smooth Tex., Va., Wash., W.Va.; Mexico; South America (Chile); awns, and also by larger and less obscure leaf cells. It s Europe; e Asia (Japan); s Africa; Pacific Islands (New should be noted that leaves of S. bartramii sometimes Zealand); Australia. show 2-stratose patches (one or a few cells in width). In This treatment follows M. T. Gallego et al. (2006) in contrast, S. chisosa has leaves that are almost completely including Syntrichia pagorum with forms of S. laevipila 2-stratose distally, less twisted when dry, and merely reported in the literature from North America, but this mucronate at the apex. is tentative pending a careful reexamination of this 622 POTTIACEAE · Syntrichia

SYNTRICHIA

7. Syntrichia chisosa (Magill, Delgadillo & L. R. Stark) squarrose-recurved, 0.25–0.45 mm, green, papillose, R. H. Zander, Bull. Buffalo Soc. Nat. Sci. 32: 269. 1993 costate, with an apiculus of 1-several elongate, smooth cells. Sexual condition dioicous (perigonia and Tortula chisosa Magill, Delgadillo & sporophytes unknown). L. R. Stark, Ann. Missouri Bot. Locally common in desert scrub, thin soil in crevices Gard. 70: 200, figs. 1–9. 1983 of rocks, soil around bases of shrubs and boulders; moderate to high elevations (about 1500–2700 m); Stems 2–6 mm. Leaves infolded N.Mex., Okla., Tex.; Mexico; s Africa. and spirally twisted around the Distinguishing features of Syntrichia chisosa include stem when dry, wide-spreading to the 2-stratose laminae, strongly serrate abaxial surface 5 5 5 squarrose-recurved when moist, of the costa, plane leaf margins, mucronate apex, and spatulate, 1.5–2.5 × 0.6–0.8(–1) costate, foliose propagula. In the northern part of its mm, distally 2-stratose, occasion- range, the species frequently occurs with S. bartramii (see ally with 1-stratose patches; margins plane, entire; apices comments thereunder). Syntrichia chisosa also occurs acute to truncate; costa excurrent into a short, 0.02–0.1 with S. fragilis, and the two may be confused because of mm mucro, red, rounded and sharply serrate with hyaline a superficially similar habit, color, and dry leaf stance, teeth abaxially; basal cells abruptly differentiated, those but S. chisosa can be distinguished with a handlens by near the margin smaller, short-rectangular; distal cells non-fragile leaves, a fuzzy appearance of the back of the hexagonal to irregularly polygonal, or isodiametric, 8– costa, and usually abundant propagula, and, under a 12(–13) µm, densely papillose with 3–5 papillae per cell, compound microscope, by smaller, 2-stratose, and bulging, moderately thick-walled, not collenchymatous, relatively obscure laminal cells. obscure. Specialized asexual reproduction by propagula borne on stalks in axils of distal leaves, leaf-like, Syntrichia · POTTIACEAE 623

8. Syntrichia ammonsiana (H. A. Crum & L. E. distinct neck; operculum 1–1.5 mm, red; peristome 1– Anderson) Ochyra, Fragm. Florist. Geobot. 37: 212. 1.5 mm, teeth twisted about 1/2 turn, the distal divisions 1992 yellow, the basal membrane pale, about 1/4 the total Tortula ammonsiana H. A. Crum & length. Spores 13–20 µm, densely papillose. L. E. Anderson, Bryologist 82: 469. Bark of trees, rock (usually calcareous), occasionally figs. 3–5. 1979 soil; low to high elevations; Ariz., N.Mex., N.C., Okla., Tenn., Tex., Va., W.Va.; Mexico; Central America; South Stems 5–10 mm. Leaves infolded America; Europe; Asia (China, Iran); Pacific Islands and twisted when dry, recurved (Hawaii). when moist, broadly spatulate, 5 5 Syntrichia fragilis shows considerable variability in size 5 1.5–2.5 × 0.6–0.8 mm; margins and leaf shape (apparently correlated with habitat plane, entire before but with a few conditions). In some small, corticolous plants, extreme teeth near the apex; apices acute; fragmentation is evident, with an abnormal development costa percurrent, yellow or brown, smooth; basal cells of the lamina beyond the usual outline of the leaf. In abruptly differentiated, narrower toward the margins; such plants, several regions of each leaf seem to remain distal cells quadrate to hexagonal, 10–15 µm, bulging, meristematic and produce scalloped or ruffled extensions with about 4 papillae per cell. Specialized asexual that eventually break off. Fragility of leaves should not reproduction propagula borne on stalks in axils of distal be considered an infallibly diagnostic character, however, leaves, leaf-like, 0.25–0.45 mm, green, papillose, costate. since some plants of S. fragilis have quite firm leaves, Sexual condition dioicous (perigonia and sporophytes and the leaves of some other species, particularly when unknown). old, may become broken. Sandstone in deep shade; moderate elevations; N.C., Tenn., W.Va.; South America (Peru); Africa (South 10. Syntrichia sinensis (Müller Hal.) Ochyra, Fragm. Africa). Florist. Geobot. 37: 213. 1992 Syntrichia ammonsiana can easily be distinguished from S. chisosa by its 1-stratose laminae. Barbula sinensis Müller Hal., Nuovo Giorn. Bot. Ital., n. s. 3: 100. 1896; 9. Syntrichia fragilis (Taylor) Ochyra, Fragm. Florist. Tortula sinensis (Müller Hal.) Geobot. 37: 212. 1992 Brotherus Tortula fragilis Taylor, London J. Stems 4–15 mm. Leaves longitudinally folded and spirally twisted Bot. 6: 333. 1847 5 5 around the stem but little crisped Stems (5–)10–25 mm. Leaves when dry, wide-spreading when crowded, longitudinally folded moist, oblong-lingulate to spatu- and spirally twisted around the late, 2–4.5 × 0.6–1.6 mm; margins revolute in the stem (but little crisped) when dry, 1 5 5 proximal /2, entire; apices acute; costa excurrent into a 5 5 5 5 5 5 wide-spreading when moist, smooth to slightly toothed, hyaline awn, brown or oblong-lingulate to spatulate, 2– reddish, smooth; basal cells abruptly differentiated, 3.5 × 0.75–1 mm, fragile, with narrower toward the margins; distal cells polygonal, or sheets of cells breaking off, sometimes along lines of quadrate, 12–20 µm, with 8–10 papillae per cell; marginal 1 weakness; margins revolute before to as much as /2 the cells not differentiated. Specialized asexual reproduction leaf length, to plane, entire or crenulate; apices truncate absent. Sexual condition autoicous. Seta red, 15–25 to acute; costa percurrent or slightly excurrent as a mucro mm. Capsule red, 3–3.8 mm, straight or slightly curved, 1–3(–5) cells long, yellow or red, finely to strongly with a distinct neck; operculum 1.2–1.5 mm, red; papillose abaxially, abruptly tapered; basal cells abruptly peristome 0.8–1.1 mm, red, the basal membrane pale, differentiated, becoming rather abruptly short- about 1/4 the total length. Spores 12–18 µm, papillose. rectangular near the margins; distal cells quadrate- Vertical limestone faces; high elevations; Colo., hexagonal, 9–15 µm, bulging, with 3–8 papillae per cell, N.Mex.; Europe; Asia; n Africa. with moderately thick walls, not particularly Only recently discovered in the Rocky Mountains, collenchymatous; distal marginal cells not or weakly to Syntrichia sinensis may have been overlooked elsewhere strongly differentiated as a border of brownish, thicker- in the flora area. For example, it is to be expected in the walled cells in about 2–3 rows. Specialized asexual northern part of the Sierra Nevada of California where reproduction absent. Sexual condition dioicous. Seta limestone is exposed. red, 10–15 mm. Capsule red, (1.5–)2–4 mm, slightly curved, rather gradually tapered to the seta or with a 624 POTTIACEAE · Syntrichia

11. Syntrichia montana Nees, Flora 2: 301. 1819 retuse, occasionally truncate or acute; costa excurrent Syntrichia intermedia Bridel; Tortula into a toothed, hyaline awn (often brown at base) usually intermedia (Bridel) De Notaris; longer than the leaf, yellow or brown, often minutely T. ruralis var. crinita De Notaris papillose abaxially (but not serrate because of projecting cell ends); basal cells abruptly differentiated, rectangular, Stems 2–10 mm. Leaves infolded 5 5 70–90(–100) × 22–40 µm, often with yellow walls,

5 and twisted when dry, erect- 5 5 5 narrowly rectangular at the margins; distal cells quadrate 5 5 5 spreading when moist, lingulate or 5 to polygonal, 15–23 µm, thin-walled, pellucid, bulging 5 5 spatulate, 1.5–3 × 0.5–1.5 mm; and bearing 4–7 papillae per cell. Specialized asexual margins revolute in the proximal reproduction absent. Sexual condition autoicous, 1 /2, entire; apices broadly acute or although perigonia often lacking, apparently sometimes obtuse, sometimes emarginate; costa excurrent into a dioicous. Seta red-brown, 10–15 mm. Capsule yellowish short, serrate, hyaline awn, brown or red, often papillose or reddish brown, 3–4.5 mm, straight or slightly curved, abaxially and serrulate near the apex because of with an abrupt neck; operculum 1.5–2 mm, reddish projecting cell ends; basal cells abruptly differentiated, brown; peristome ca. 1.5 mm, the distal divisions twisted narrower toward the margins; distal cells polygonal or ca. 2 turns, yellow or red, the basal membrane white, 1/3 quadrate, 8–12 µm, with 4–6 papillae per cell. Specialized the total length. Spores 9–16 µm, papillose. asexual reproduction absent. Sexual condition dioicous. Soil, rock, rarely the bases of trees; moderate to high Seta red, 8–14 mm. Capsule red, 2–3.5 mm, straight or elevations; Ariz., N.Mex., Tex.; Mexico; South America slightly curved; operculum 1.2–2 mm, red; peristome 0.5– (Bolivia, Peru). 1 1.3 mm, the basal membrane to /2 the total length, red. Syntrichia obtusissima, with a distinctive Southwest Spores 10–13 µm, papillose. and Mexican-Andean disjunction, has been much Widespread on soil and rock, occasionally on tree bark; confused with S. ruralis, leading to many misidentified moderate to high elevations; Alta., B.C.; Ariz., Calif., specimens in herbaria, but the large, pellucid leaf cells Idaho, Maine, Mont., Nev., N.Mex., N.Y., Oreg., Wash.; (about 15–23 µm) contrast with those of S. ruralis (about Europe; Asia. 8–12 µm), and the back of the costa lacks serrations from This treatment follows M. T. Gallego et al. (2006) in projecting cell ends. Furthermore, it has a clear central employing Syntrichia montana to encompass what has strand in the stem, and hydroids in the costa, neither of been called S. intermedia or S. ruralis var. crinita in North which is found in S. ruralis. America. This is, however, a tentative decision as there remains an incompletely understood complex of small, 13. Syntrichia princeps (De Notaris) Mitten, J. Proc. dioicous plants with hydroids in the costa, and some Linn. Soc., Bot., suppl. 1: 39. 1859 currently undescribed taxa may yet need to be recognized. One recently described species that falls in this complex Tortula princeps De Notaris, Mem. is S. rupicola B. H. Allen. Further field sampling, Reale Accad. Sci. Torino 40: 288. molecular characterization, and culture studies are 1838 necessary before these taxa are fully understood. Stems 5–20 mm. Leaves usually 5

5 in distinct whorls, infolded, 5 5 5

5 12. Syntrichia obtusissima (Müller Hal.) R. H. Zander, 5 somewhat contorted, and weakly 5 Bull. Buffalo Soc. Nat. Sci. 32: 269. 1993 5 to strongly twisted around the Barbula obtusissima Müller Hal., stem when dry, wide-spreading to Syn. Musc. Frond. 1: 640. 1849; slightly recurved when moist, Tortula obtusissima (Müller Hal.) concave, spatulate, 2–4 × 1–1.5 mm; margins revolute in 1 3 Mitten the proximal /2– /4, entire; apices acute or sometimes truncate; costa excurrent into a long, serrate, hyaline awn Stems (5–)10–20 mm. Leaves (reddish at base), often strongly papillose abaxially and clasping at base, infolded, and serrulate near the apex because of projecting cell ends, 5 5 5 twisted around the stem when dry, red; basal cells abruptly differentiated, long-rectangular, wide-spreading to squarrose when 45–80 × 20–30 µm, short-rectangular to quadrate at the moist, lingulate to spatulate, 3–4 margins; distal cells quadrate to hexagonal, 12–17 µm, × 1–1.5 mm, keeled; margins revolute in the proximal slightly bulging, bearing 4–6 papillae per cell. Specialized 3 7 /4– /8, entire, often laxly undulate; apices emarginate to asexual reproduction absent. Sexual condition synoicous Syntrichia · POTTIACEAE 625

SYNTRICHIA ° MICROBRYUM

(apparently rarely dioicous). Seta red, 10–18 mm. 14. Syntrichia caninervis Mitten, J. Proc. Linn. Soc., Capsule brownish red, 3–4 mm, slightly curved, with a Bot., suppl. 1: 39. 1859 distinct neck; operculum 1.5–2 mm, brown; peristome Tortula bistratosa Flowers; ca. 1.5 mm, the distal divisions twisted about 2 turns, T. caninervis (Mitten) Brotherus red, the basal membrane white, 1/2–2/3 the total length. Spores 9–13 µm, papillose. Stems 3–20 mm. Leaves infolded and imbricate, not to weakly 5 Humus, soil, rock, tree bark; low to moderate 5

5 twisted around stem when dry, 5 elevations; B.C.; Ariz., Calif., Idaho, Mont., Nev., Oreg., 5 5 5 5 5 erect-spreading when moist, Utah, Wash.; Mexico; w, s South America; Europe; 5 5 5 w Asia; Africa; Pacific Islands (Hawaii, New Zealand); 5 ovate-spatulate, 1–2.5 × 0.6–1.2 Australia; Antarctica. mm, 2-stratose or thicker, occa- The synoicous condition of Syntrichia princeps is sionally with scattered 1-stratose diagnostic if present, but otherwise one must rely on wider patches; margins revolute for the entire length of leaf, basal leaf cells, costal hydroids, and the stem central entire; apices acute to acuminate; costa excurrent into a strand to separate this species from S. ruralis, S. serrate, hyaline awn that is often broadly hyaline at base, papillosissima, and S. norvegica. The more acute leaves brown or blackish, strongly papillose; basal cells abruptly with cells generally smaller, and costa reddish and differentiated, narrower toward the margins; distal cells serrulate separate it from S. obtusissima. rounded, polygonal, or quadrate, 8–13 µm, with 4–6 low papillae per cell. Specialized asexual reproduction absent.