Trachyxiphium guadalupense (Brid.) W.R.Buck

  • Authority

    Buck, William R. 1998. Pleurocarpous mosses of the West Indies. Mem. New York Bot. Gard. 82: 1-400.

  • Family

    Pilotrichaceae

  • Scientific Name

    Trachyxiphium guadalupense (Brid.) W.R.Buck

  • Description

    Species Description - Plants small and slender, in ± lustrous, whitish green to golden, mostly thin mats. Stems creeping, to ca. 4 cm long, red, irregularly but freely branched, sometimes ± pinnate, ± densely foliate, sometimes complanate-foliate; in cross-section without a hyalodermis, over 1-2(-3) rows of small firm- to thick-walled cells surrounding several large thin-walled cells, central strand none; pseudoparaphyllia small, foliose; axillary hairs 2-celled, with a short brown basal cell and an elongate hyaline distal cell. Leaves sometimes ± contorted when dry, sometimes falcate-secund, flaccid when moist, erect to wide-spreading, lanceolate to ovate-lanceolate to oblong-lanceolate, 0.85-1.4(-2) mm long, gradually long-acuminate, the apex sometimes flexuose, ± plicate, shallowly concave, the apical cell often 2-pronged, narrowed to but not rounded at the insertion; margins not bordered, usually coarsely serrate in the acumen, all upper marginal cells forming bifid, ± swollen teeth, subentire to serrulate below, plane or erect near midleaf; costa double, ending 2/3-3/4 the leaf length, ± parallel, subequal, toothed, the teeth often bifid, ± crested in upper 1/2; cells long-hexagonal to linear, smooth or prorulose (especially above), thin- to firm-walled, ± porose, scarcely differentiated toward the leaf base except in 2(-3) rows across the insertion where shorter, broader, and colored; alar cells not differentiated. Asexual propagula none. Polyoicous, but mostly autoicous. Peri-chaetia small, inconspicuous; leaves ± erect with spreading, often flexuose apices, lanceolate to oblong-lanceolate, 1-1.7 mm long, gradually or ± abruptly long-acuminate; margins coarsely serrate in the acumen, the teeth often bifid, entire below, plane; costa double, ending 1/5-1/4 the leaf length, rarely absent, not projecting at apex; cells linear above, smooth, thin- to firm-walled, porose, becoming long-rectangular and lax below. Setae elongate, smooth or more often slightly roughened below urn, reddish, 0.7-2 cm long, ± flexuose, curved at apex; capsules inclined to pendent, short-cylindric, 0.5-1.4 mm long, with a well-defined neck; exothecial cells subquadrate to rectangular, collenchymatous; annulus of 5-8 rows of small subquadrate thin-walled cells, often remaining attached to mouth of urn, tardily deciduous; operculum rostrate from a high-conic base; exostome teeth yellow-brown, narrowly triangular, not or scarcely bordered, on the front surface with a median furrow with a zig-zag line down it, the plates cross-striolate below, coarsely papillose above shoulder, not or slightly trabeculate at back, finely papillose; endostome with a medium-high, smooth to finely papillose basal membrane, segments papillose-spiculose, keeled, narrowly perforate, with baffle-like crosswalls, cilia none. Spores spherical, finely papillose, 11-15 µm diam. Calyptrae mitrate, shallowly lobed at base, naked or with a few scattered hairs, usually roughened above, occasionally smooth.

  • Discussion

    1. Trachyxiphium guadalupense (Brid.) W. R. Buck, Brit-tonia 39: 220. 1987; Hypnum guadalupense Brid., Muscol. Recent. Suppl. 2: 96. 1812; Hookeria guadalupensis (Brid.) Miill. Hal., Syn. Muse. Frond. 2: 212. 1851; Hookeriopsis guadalupensis (Brid.) A. Jaeger, Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1875-76: 362. 1877. Plate 27, figures 1-8 Hookeria falcata Hook., Musci Exot. 1: 54. 1818; Pterygophyllum falcatum (Hook.) Brid., Bryol. Univ. 2: 353. 1827; Hookeriopsis falcata (Hook.) A. Jaeger, Ber. Thátigk. St. Gallischen Naturwiss. Ges. 1875-76: 363. 1877. Hookeria repens Hook. & Grev., Edinburgh J. Sci. 2: 231. 1825. Hookeria falcatula Schimp. ex Besch., Ann. Sci. Nat. Bot. VI, 3: 237. 1876; Hookeriopsis falcatula (Besch.) A. Jaeger, Ber. Thätigk. St. Gallischen Naturwiss. Ges. 1875-76: 363. 1877. Hookeria guadalupensis var. longifolia Besch., Ann. Sci. Nat. Bot. VI, 3: 238. 1876. Hookeria hypniformis Besch., Ann. Sci. Nat. Bot. VI, 3: 237. 1876; Hookeriopsis hypniformis (Besch.) A. Jaeger, Ber. Thátigk. St. Gallischen Naturwiss. Ges. 1875-76: 362. 1877. Hookeria rufa Schimp. ex Besch., Ann. Sci. Nat. Bot. VI, 3: 237. 1876; Hookeriopsis rufa (Besch.) A. Jaeger, Ber. Thátigk. St. Gallischen Naturwiss. Ges. 1875-76: 363. 1877. Hookeria tenella Schimp. ex Besch., Ann. Sci. Nat. Bot. VI, 3: 237. 1876, nom. nud. in syn. Hookeria versicolor Schimp. ex Besch., Ann. Sci. Nat. Bot. VI, 3: 238. 1876; Hookeriopsis versicolor (Besch.) A. Jaeger, Ber. Thátigk. St. Gallischen Naturwiss. Ges. 1875-76: 362. 1877. Hookeria dimorpha Müll. Hal., Bull. Herb. Boissier 5: 564. 1897; Hookeriopsis dimorpha (Müll. Hal.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 939. 1907. Hookeria harrisii Müll. Hal., Bull. Herb. Boissier 5: 564. 1897; Hookeriopsis harrisii (Müll. Hal.) Broth. in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 940. 1907. Discussion. Trachyxiphium guadalupense is characterized by slender plants with lanceolate to ovate-lanceolate leaves, often somewhat falcate-secund, with long-acuminate apices. The upper leaf margins are typically coarsely serrate, with bifid, swollen teeth. It is distinguished from T. vagum by its more diminutive stature and smaller leaves. More significantly, in T. guadalupense the marginal teeth are mostly swollen and often bifid, whereas in T. vagum, when teeth are present, they are small, not swollen, and never bifid. I have interpreted this extraordinarily common species very broadly after examination of numerous specimens. “Hookeriopsis” falcata is only an ecotype of T. guadalupense. Indeed, in several specimens the middle of the colony was typical ‘falcata,” but the margins, growing in a more shaded or protected regime, were typical guadalupense. Even if one were to recognize two species, only falcate rather than straight leaves is available as a differentia. There is a form of T. guadalupense in the Lesser Antilles in which the majority of leaves on each stem are somewhat broader than usual, and in these broader leaves the costa is weaker. This form is represented by the types ot Hookeriopsis hypniformis, H. rufa, and H. falcatula. However, in these forms some typically narrower leaves are always present and in typical 7. guadalupense a few broader leaves can often be found. The type of Hookeriopsis dimorpha has somewhat more oblong leaves than is typical, but this is a commonly encountered phenomenon in the Greater Antilles. When plants are somewhat more robust, the leaves are often more oblong and the stems, but not the branches, sometimes have slightly enlarged stem epidermal cells. The type of Hookeriopsis harrisii is depauperate and the marginal teeth on the leaves are poorly developed.

  • Distribution

    Range. Mexico to Panama, Venezuela to Bolivia, Trinidad; Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico, St. Kitts, Guadeloupe, Dominica, Martinique, St. Lucia, St. Vincent; growing most often on soil or clay, also on rotten logs, humus, and bases of trees, rarely on rock, in humid forests, usually below 1500 m.

    Mexico North America| Central America| Venezuela South America| Colombia South America| Ecuador South America| Peru South America| Bolivia South America| Brazil South America| Trinidad and Tobago South America| Cuba South America| Jamaica South America| Haiti South America| Dominican Republic South America| Puerto Rico South America| Saint Kitts and Nevis South America| Guadeloupe South America| Dominica South America| Martinique South America| Saint Lucia South America| Saint Vincent and the Grenadines South America|