(Last Modified On 11/4/2011)
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Acceptance
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Accepted
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(Last Modified On 11/4/2011)
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Nomenclature:
74. SYNTRICHIA Plates 105, 106, 107, 108, 109, 110– 111. Syntrichia Brid., J. Bot. (Schrader) 1(2): 299, 19 April 1801 (vide Sayre 1959). Type: Syntrichia ruralis (Hedw.) Web. & Mohr, lectotype fide Zander, Phytologia 65: 432, 1989. Tortula subg. Syntrichia (Brid.) Chev., Fl. Gén. Env. Paris 2: 52, 1827. Barbula subg. Syntrichia (Brid.) BSG, Bryol. Eur. 2:10, 1851 (fasc. 46–47 Consp. 2: III). Tortula sect. Syntrichia (Brid.) Lam. & Cand., Syn. 100, 1806. Tortula sect. Rurales De Not., Mem. R. Acc. Sc. Torino 40: 286, 1838. Type: Tortula ruralis (Hedw.) Gaetrn., Meyer & Scherb. Barbula sect. Rurales BSG, Bryol. Eur. 2: 101, 1842 (fasc. 13–15 Mon. 39). Barbula sect. Syntrichia (Brid.) C. Müll., Syn. 1: 632, 1849. Barbula sect. Vallidens C. Müll., Linnaea 42: 347, 1879, nom. inval. Type: Barbula percarnosa C. Müll. Barbula sect. Syntrichiae Lesq. & James, Man. N. Amer. Moss. 130, 1884, nom. illeg. Barbula sect. Ruraliformes Kindb., Eur. N. Amer. Bryin. 2: 245, 1897, nom. illeg. incl. sect. prior. Type: Barbula ruralis Hedw. Syntrichia sect. Eusyntrichia Moenk., Laubm. Eur. 306, 1927, nom. illeg.
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Habitat:
Found on rock, soil and bark on all continents, most commonly in temperate areas but also characteristic of dry climates.
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Notes:
Syntrichia is segregated from Tortula s. lat. by the combination of red KOH reaction of the upper laminal cells, lack of narrowly elongate upper laminal marginal cells, the crescent-shaped transverse section of the stereid band, and the general lack of differentiated dorsal costal epidermal cells. This concept is essentially that of Kramer (1980, 1988), who emphasized the exposed dorsal stereid band (Pl. 105, f. 7, 15), not covered dorsally by parenchymatous or otherwise differentiated epidermal cells. Recently Ochyra (1992) supported this concept (Zander 1989) as “a natural group that deserves recognition as a genus of its own” with a series of new combinations appropriate for the Polish flora. Syntrichia is distinguished from Hennediella (likewise KOH red) by the leaves ligulate to spathulate or very seldom lanceolate, margins usually recurved and seldom dentate or bordered, upper laminal cells smaller and superficially strongly convex, costa commonly excurrent as an awn, almost always lacking a dorsal costal epidermis, stereid band semicircular to crescent-shaped, and sporophytes not in a reduction series within the genus. Note that in some few species (e.g. S. brandisii) a dorsal epidermis is very weakly differentiated (seen as somewhat wider lumens in costal transverse section), but these species are placed here rather than with Hennediella because of their recurved, unbordered margins and small upper laminal cells. Syntrichia costesii (Pl. 107, f. 17–19), like certain species of Hennediella, has an intramarginal border of differentiated cells, but those cells are isodiametric and the costa lacks a differentiated dorsal epidermis. The existence of a weakly differentiated dorsal epidermis in some species may indicate a derivation of Syntrichia from Bryoerythrophyllum, which differs, in traditional characters, in the presence of a second stereid band and usually narrower (broadly lanceolate to ligulate) leaves. Most cladograms in the phylogenetic analysis show Syntrichia and Bryoerythrophyllum to be quite distant. A few species, like S. laevipila (Pl. 109, f. 4–5), may occasionally and perhaps abnormally have one or two stereid or substereid cells present ventrally between the guide cells and the ventral epidermis as a tiny second stereid band, while in the type (isotype, NY) of S. rubra (Pl. 111, f. 5–8) and a second specimen seen (as Tortula rubra var. subantarctica, Campbell I., Sorensen 1946, isotype, NY), the ventral stereid band is of several stereid cells, the ventral epidermis is lacking, and superficially, the ventral surface of the costa is similar to the dorsal surface, being of superficially elongate, simply papillose cells. Syntrichia percarnosa (Pl. 109, f. 20–22) has much the same leaf morphology as Trichostomum crispulum, and the former species may well belong with that genus; the substereid cells of the costa are, however, arranged more like those of Syntrichia. Certain species of Didymodon sect. Vineales (KOH red) may lack a ventral stereid band, but have lanceolate leaves and narrowly rectangular basal cells. Bryoerythrophyllum and Mironia species are also KOH red and may have long-ligulate leaves, but the transverse section of the costa is reniform in section and the stem has a sclerodermis. Syntrichia geheebiaeopsis (Pl. 108, f. 13–17, cf. discussion by Lightowlers 1985a as Tortula) has many of the characters of Bryoerythrophyllum and Mironia, including broadly lanceolate, dentate leaves with a sheathing leaf base, small upper laminal cells with low, crowded papillae. It further differs from Syntrichia by the very narrowly rectangular basal cells. Bryoerythrophyllum and Mironia have semicircular to reniform costal sections, however, with usually two distinct stereid bands and a differentiated dorsal epidermis, but S. geheebiaeopsis has the typical costal morphology of Syntrichia: a nearly circular costal section, with a single stereid band and no differentiated dorsal epidermal cells. It mayprove to be a good genus in the Merceyoideae apparently having lost, like Streptopogon, the ventral stereid band. Syntrichia cavallii (Pl. 107, f. 7–12) is unusual in its strongly differentiated perichaetial leaves that are similar to those of S. papillosa (sect. Collotortula); it is, however, apparently related to S. percarnosa, instead. Syntrichia cavallii differs from Calyptopogon, in which perichaetial leaves are differentiated, in that propagula are lacking and the upper laminal papillae are multiplex. Willia also has strongly differentiated perichaetial leaves, but these are usually somewhat secund, and the sporophyte is distinctively reduced in length and complexity. Syntrichia cavallii is here placed in sect. Syntrichia, not sect. Collotortula, because of the lack of collenchymatous thickenings in the upper laminal cell walls. Eventually, perhaps, further study may require that a separate section or genus be devised for S. cavallii (see also discussion under Willia). Syntrichia sect. Collotortula Zand., sect. nov. Type: Syntrichia andicola (Mont.) Zand. A sectione typica cellulis laminalibus in regione mediana superna plerumque distincte in angulis incrassatis vel tumescentitrigonis, marginibus folii plerumque recurvis, papillis interdum simplicibus, propagulis si effectis clavatis vel ellipticis differt. Differs from the typical section by the following combination of characters: medial upper laminal cells usually somewhat thickened at the corners or even trigonous (i.e. with bulging knots), leaf margins usually recurved, papillae sometimes simple, and propagula when present clavate or elliptical. Examination of transverse leaf sections indicates that the interior upper laminal cell walls may have large, round central pores (staining helps define this) in at least some species (Syntrichia aculeata, S. amphidiacea, S. andicola (Pl. 106, f. 19), S. bogotensis, S. gemmascens, S. gromschii and S. papillosa), while in other species, including those of other sections of Syntrichia, the pores are absent or what appear to be interior pores are occasional, irregular and possibly artifacts. Features correlated with laminal cell collenchymatous thickenings are the upper leaf margin usually serrate and the stem central strand often lacking, but these are not unique characters. The section may not be sharply distinct from sect. Syntrichia because certain species of that section may have weakly thickened cell corners (appearing as bright triangular points of light under high magnification). The counterclockwise-twisted seta of Syntrichia papillosa commented upon by Dixon (1923) as unusual is not taxonomically significant, since long setae in the Pottiaceae are generally twisted clockwise below and counterclockwise above, and short setae are untwisted or merely twisted clockwise. The seta of S. papillosa (Pl. 109, f. 19—from a specimen misidentified as Tortula panduraefolia, Tasmania, Weymouth 2821, NY) is only about 5 µm in length. Species (some surely synonyms of S. andicola) belonging to sect. Collotortula include: S. aculeata, S. alpestris, S. amphidiacea (Pl. 106, f. 1–8), S. andicola (Pl. 106, f. 14–20), S. antarctica (possibly belongs here, but laminal cell walls are only weakly collenchymatous), S. bogotensis, S. cainii (Pl. 107, f. 5–6), S. ciliata, S. conferta, S. fontana (laminal cells flat superficially, as in Hennediella), S. gemmascens (Pl. 106, f. 18–21), S. goudotii, S. gromschii, S. mollis, S. papillosa (Pl. 109, f. 14–19), S. rivularis (Pl. 109, f. 20–23), S. robusta (Pl. 111, f. 1–4), S. rubra (Pl. 111, f. 5–8), and S. subaristata. Curiously, S. rigescens has propagula (Pl. 110, f. 18–19) borne ventrally on the costa, as in sect. Collotortula, but is clearly in sect. Syntrichia near S. caninervis. Note also Syntrichia leucostega, not seen, for which ventral costal propagula are illustrated by Kramer (1988). Syntrichia sect. Aesiotortula Zand., sect. nov. Type: S. pagorum (Milde) Amann. A sectione typica plantis parvioribus quam congeneribus, foliis ligulatis vel spathulatis, marginibus omnino planis, papillis bifidis, propagulis si effectis foliaceis, in termino caulis vel in apicibus foliorum deciduis portatis, costa supra regione folii mediana perincrassata et in sectione transversalis semicircularibus differt. Differs from the typical section by the following combination of characters: plants rather small for the genus, leaves ligulate to spathulate, margins plane throughout, papillae bifid, and propagula when present leaf-like, borne terminally on the stem or as deciduous leaf apices. The costa is often very strongly thickened above midleaf and semicircular in transverse section. This group of species includes S. ammonsiana (Pl. 105, f. 12–16), S. baileyi, S. bartramii, S. chisosa (Pl. 107, f. 13–16), S. epilosa (Pl. 108, f. 1–9), S. pagorum (Pl. 109, f. 10–11), S. phaea (Pl. 109, f. 23–27) and S. pygmaea (Pl. 110, f. 10–16). Syntrichia papillosa, although here placed with sect. Collotortula because of the clearly trigonous upper laminal cells and clavate to spherical propagula, also has plane margins and a much thickened costa. Section Aesiotortula (as the “Tortula laevipila-Tortula pagorum-Gruppe”) was not dealt with by Kramer (1980), who viewed it as a complex requiring special study. Certain of the infraspecific taxa of S. laevipila may also belong here, but not var. laevipila (Pl. 109, f. 1–9) itself. Syntrichia pygmaea is only tentatively placed in this section; it is propaguliferous, however, by a deciduous leaf apex and has plane margins. On the other hand, species of similarly small stature in many genera have a tendency to lose or exhibit less distinctly some important characters, including recurvature of the lower margins. Syntrichia pygmaea is also unusual for its ventral leaf surface very narrowly grooved along the costa and ventral costal cells elongate, which may be an indication of a relationship with the Bryoerythrophylleae for this species. The upper laminal cells of the most highly derived of the species of sect. Aesiotortula are relatively large for the genus, generally 13–15 µm in diameter; species with upper laminal cells small (ca. 8–10 µm in diameter), such as S. bartramii and S. chisosa, are less distinctive. The cleistocarpous genus Phascopsis could be seen as having been derived from this section of Syntrichia, but is apparently a relict of a more primitive lineage (see Cladograms 13 and 14). The New World austral species Syntrichia epilosa is much the same as S. bartramii of western North America and maybe synonymous; a parallel southern South America and southwestern North America distribution is that of the austral Pseudocrossidium crinitum and its Arizona population previously known as Tortula aurea (see treatment of Pseudocrossidium).
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Literature:
Allorge (1938), Anderson (1943), Barkman (1963), Bartram (1924b, 1926b), Bewley (1972, 1973a,b), Bewley et al. (1974), Bizot (1954, 1956), Blomquist (1930), Boudier (1992), Casas de Puig (1975a), Casas de Puig and Molinas (1975), Catcheside (1980, 1992), Dedkov et al. (1989), Doei et al. (1985), El-Oqlah et al. (1988), Hedenäs (1989b), Kalenov (1977), Kramer (1978), Lazarenko (1959), Lightowlers (1985a, 1986a,b,c), Magill et al. (1983), Maya (1986), Mishler (1984a, 1985a,b, 1986a, 1987a, 1990), Mishler and Newton (1987, 1988), Mishler and Oliver (1991), Mishler and Scheirer (1983), Oliver and Mishler (1988, 1990), Ovezova (1989), Saito (1973a), Side and Whitehouse (1974), Steere (1939a, 1940), Stone (1971), Studlar et al. (1984), Toth (1987), Tuba (1984, 1985), Willis (1964), Zander (1989).
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Number of accepted species:
82
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Species Examined:
S. aculeata (BUF, NY), S. alpestris (BM), S. ammonsiana (BUF), S. amphidiaceus (BM, BUF, TENN), S. amplexa (CU), S. anderssonii (NY), S. andicola, S. antarctica (NY), S. baileyi (NY), S. bartramii (BUF), S. bipedicellata (NY), S. bogotensis (NY), S. bolanderi (BUF), S. brandisii (NY), S. cainii (BUF, TRTC), S. caninervis (BUF, H), S. cavallii (NY, US), S. chisosa (BUF), S. ciliata (H), S. conferta (NY), S. costesii (NY), S. didymodontoides (H), S. epilosa (COLO), S. filaris (H, US), S. flagellaris (BUF), S. fontana (S) as Tortula rivularis, S. fragilis, S. fuscoviridis (NY), S. geheebiaeopsis (NY), S. gemmascens (NY), S. gromschii (US), S. inermis, S. intermedia (BUF), S. jaffuelii (NY), S. lacerifolia (NY), S. laevipila (BUF), S. latifolia, S. limensis (NY), S. linguifolia (L), S. longimucronata (NY), S. mongolica (NY), S. mollis (US), S. norvegica, S. obtusissima (BM, BUF, TENN), S. papillosa (BUF, NY), S. percarnosa (BUF, H, US), S. phaea (BUF), S. pichinchensis (US), S. princeps, S. prostrata (US), S. pseudodesertorum (S), S. pseudorobusta (NY), S. pygmaea (BM, BUF, MICH, NY), S. ramosissima (NY), S. reflexa (NY), S. rigescens (FU), S. robusta (NY), S. rubella (NY), S. rubra (NY), S. ruralis, S. saxicola (NY), S. scabrella (NY), S. scabrinervis (US), S. schnyderi (NY), S. serrata (NY), S. serripungens (NY), S. sinensis (NY), S. socialis (S), S. subaristata (NY), S. virescens (BUF), S. viridula (NY).
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Plants usually coarse, forming often deep turf, green, occasionally reddish or blackish above, reddish brown below. Stems branching occasionally, 1–4(–12) cm in length, transverse section rounded-pentagonal, central strand present or absent, sclerodermis absent or occasionally of 1–2 layers of substereid cells, hyalodermis absent or present, sometimes collapsed; axillary hairs ca. 3–10 cells in length, basal 1–3 cells thicker walled or all hyaline; rhizoids common, often dense. Leaves appressed to weakly spreading when dry, spreading to squarrose when moist, narrowly ligulate to broadly spathulate, occasionally broadly lanceolate, (1.5–)4–7 µm (inclusive of awn) in length, upper lamina broadly channeled to keeled, often narrowly grooved along costa, margins plane to recurved, rarely broadly incurved, usually entire, occasionally serrulate to dentate above, occasionally bordered with thick-walled, less papillose cells, these occasionally intramarginal or rarely elongate; apex rounded to broadly acute, occasionally narrowly acute or cucullate; base not differentiated in shape to elliptical; costa often stout, commonly prominent dorsally, ending several cells before apex to excurrent as a long, often hyaline, often serrate, occasionally flattened awn, costa with lamina inserted at 45°,costal superficial cells rounded-quadrate, papillose, occasionally elongate and smooth near apex ventrally, dorsally elongate, papillose to denticulate or spinose, occasionally nearly smooth, 2–4 rows of cells across costa ventrally at midleaf, costal transverse section round, occasionally elliptical or semicircular, stereid bands ventrally absent or very rarely of a few substereid or stereid cells, dorsally present and crescent-shaped, occasionally semicircular, ventral epidermis present, the dorsal usually absent, guide cells 2–4 per layer in 1–4 layers, hydroid strand absent or present, occasionally multiple; upper laminal cells rounded-quadrate, ca. 11–15(–20) µm in width, 1(–2):1, occasionally bistratose entirely or in patches, walls thin or occasionally collenchymatous and interiorly porose, superficially strongly convex on both sides; papillae ca. (1–)4–8 per lumen, usually bifid, occasionally simple, solid or hollow, rarely simple; basal cells differentiated across base, rising higher medially, often sharply differentiated from the upper cells, occasionally inflated medially, 18–30 µm in width, 2–6:1, walls thin, sometimes irregularly porose, 3–6 rows of basal marginal cells usually narrowly rectangular and thicker walled. Propagula occasionally present, variously clusters of small, deciduous leaves; rhizoid-borne tubers; very fragile cauline leaves or leaf tips (rarely deciduous); obovate or clavate or raspberry-shaped propagula found on ventral surface of costa or medially or marginally on upper lamina. Dioicous or monoicous (then usually autoicous or synoicous). Perichaetia terminal, inner leaves usually little differentiated in size and shape, rarely enlarged and sheathing, lower cells rhomboidal, rarely throughout leaf. Perigonia gemmate, terminal or lateral as stalked buds, paraphyses often clavate. Seta elongate, (0.8–)1.0–3.0 cm in length, 1(–2) per perichaetium, reddish brown, twisted counterclockwise; theca 2–6 µm in length, reddish brown, cylindrical, commonly slightly curved, exothecial cells rectangular, 20–30 µm in width, ca. 4–6:1, walls thin to evenly thickened, capsule neck occasionally distinct, stomates phaneropore, at base of theca, annulus of 2–4 rows of vesiculose cells, persistent; peristome teeth 32, filamentous, densely spiculose, ca. 1000–2000 µm in length, with many articulations, twisted counterclockwise ca. once, basal membrane usually present, ca. 100–800 µm in height, papillose to spiculose. Operculum conic, rather large, 1.2–2.2 µm in length, cells twisted counterclockwise. Calyptra cucullate, smooth, rather large, 3.0–4.5 µm in length. Spores 8–15 µm in diameter, light brown, lightly papillose. Laminal KOH color reaction brick red. Reported chromosome number n = 6+m, 12, 12+m, 13, 13+m, 24, 24+2m, 26, 28, 32+2m, 48.
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