Sematophyllum subsimplex (Hedw.) Mitt.

Authority

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

Family

Sematophyllaceae

Scientific Name

Sematophyllum subsimplex (Hedw.) Mitt.

Description

Species Description - Plants slender, in ± lustrous, silky, pale-green to grayish green, often extensive, thin mats. Stems creeping, dark-red, to ca. 8 cm long but mostly ca. 3-4 cm, freely and often ± regularly pinnately branched, the branches wide-spreading, short, somewhat complanate-foliate; in cross-section with 2-4 rows of small thick-walled cells surrounding large thin-walled cells, central strand absent; pseudoparaphyllia foliose; axillary hairs with 2 short brown basal cells and 2-3 elongate hyaline distal cells. Stem and branch leaves similar, erect- to wide-spreading, not at all homomallous, lanceolate-ovate to ovate, stem leaves 0.65-1.3 mm long, branch leaves 0.55-0.95 mm long, gradually acuminate, occasionally the apices twisted in stem leaves, somewhat concave; margins entire or serrulate above, entire below, plane or recurved; costa short and double or absent; cells linear to linear-flexuose, 10-20:1, usually smooth, rarely unipapillose, thick-walled, often porose, not shorter in the acumen; alar cells enlarged, inflated, usually deeply colored across the insertion, oval to oblong, 5-10 X as large as the subquadrate cells above them. Asexual propagula none. Autoicous. Perichaetial leaves erect, oblong-ovate, 0.95-1.4 mm long, gradually to ± abruptly acuminate; margins subentire to serrulate, plane or recurved; costa mostly none; cells long-rhomboidal to linear-flexuose, smooth, thick-walled, somewhat porose, becoming subquadrate to long-rectangular and colored toward the insertion; alar cells not differentiated. Setae elongate, smooth, reddish, 1-1.8 cm long; capsules horizontal to pendent, asymmetric, ovoid, 0.81.3 mm long; exothecial cells subquadrate, ± collenchymatous, becoming smaller, oblate, and evenly thin-walled in 1-2 rows at the mouth; annulus not differentiated; operculum obliquely long-rostrate; exostome teeth triangular, strongly shouldered, strongly bordered, on the front surface with a zig-zag median line, cross-striolate below, coarsely papillose above, trabeculate at back; en-dostome with a high basal membrane, segments papillose, keeled, narrowly perforate, almost as long as the teeth, cilia single or in pairs, shorter than the segments. Spores spherical, finely papillose, 14-24 µm diam. Calyptrae cucullate, naked, finely roughened above.

Discussion

6. Sematophyllum subsimplex (Hedw.) Mitt., J. Linn. Soc., Bot. 12: 494. 1869; Hypnum subsimplex Hedw., Sp. Musc. Frond. 270. 1801; Isothecium subsimplex (Hedw.) Brid., Bryol. Univ. 2: 357. 1827; Microcalpe subsimplex (Hedw.) Spruce, Cat. Musc. 13. 1867, comb, inval; Plagiothecium subsimplex (Hedw.) Besch., Mém. Soc. Sci. Nat. Cherbourg 16: 251. 1872 & in E. Fourn., Pl. Mex. 1 (Crypt.): 53. 1872; Rhaphidostegium subsimplex (Hedw.) Besch., Ann. Sci. Nat. Bot. VI, 3: 254. 1878; Rhaphidorrhynchium subsimplex (Hedw.) Broth. in Engl., Nat. Pflanzenfam., ed. 2, 11: 426. 1925. Plate 149, figures 1-10 Hypnum simplicissimum Brid., Muscol. Recent. 2(2): 189. 1801, non Warnst., Allg. Bot. Z. Syst. 5(Beih. 1): 39. 1899, hom, illeg. [= Drepanocladus aduncus (Hedw.) Warnst.]. Hypnum richardii Schwägr., Sp. Musc. Frond. Suppl. 1(2): 204. 1816, hom, illeg., non P. Beauv., Prodr. Aethéogam. 69. 1805, “Richardi” [= Pylaisiadelpha recurvans (Michx.) W. R. Buck]; Isothecium richardii Brid., Bryol. Univ. 2: 358. 1827; Microcalpe richardii (Brid.) Spruce, Cat. Musc. 13. 1867, comb, inval.; Rhaphidostegium richardii (Brid.) A. Jaeger, Ber. Thãtigk. St. Gallischen Naturwiss. Ges. 187677: 409. 1878. Taxicaulis inclinatus Müll. Hal., Hedwigia 35: 255. 1896; Isopterygium inclinatum (Müll. Hal.) Paris, Index Bryol. Suppl. 219. 1900; Rhaphidostegium inclinatum (Müll. Hal.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 1109. 1908; Rhaphidorrhynchium inclinatum (Müll. Hal.) Broth, in Engl., Nat. Pflanzenfam., ed. 2, 11: 426. 1925. Taxicaulis flavens Müll. Hal., Hedwigia 37: 256. 1898; Isopterygium flavens (Müll. Hal.) Paris, Index Bryol. Suppl. 219. 1900; Rhaphidostegium flavens (Müll. Hal.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 1109. 1908; Rhaphidorrhynchium flavens (Miill. Hal.) Broth, in Engl., Nat. Pflanzenfam., ed. 2, 11:426. 1925. ? Taxicaulis crossomitrii Müll. Hal., Hedwigia 37: 255. 1898 (fide Crum & Steere, 1957: 569); Isopterygium crossomitrii (Miill. Hal.) Paris, Index Bryol. Suppl. 218. 1900; Rhaphidostegium crossomitrii (Müll. Hal.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 1109. 1908; Rhaphidorrhynchium crossomitrii (Müll. Hal.) Broth, in Engl., Nat. Pflanzenfam., ed. 2, 11: 426. 1925. Discussion. Sematophyllum subsimplex is not as widespread and weedy in the West Indies as it is in northern South America. Once known, it is easily recognized by the pale-green or grayish green plants that are, at best development, regularly pinnate. The dark-red stems, seen through the translucent leaves when moist, and the relatively large alar cells are also helpful features. The species is perhaps only confused with Acroporium longirostre because of a similar leaf shape and large alar cells. However, in S. subsimplex the leaves are broader and not concave in the acumen as they are in A. longirostre. Certainly S. subsimplex belongs in a very different assemblage of species than either those species that precede or follow it in this treatment. Not only does it have a very different aspect but rarely the cells can be unipapillose and the calyptrae are roughened. In those latter features it is like Trichosteleum but does not seem to have a relationship with any of our species of that genus and thus, by default, is left in Sematophyllum.

Distribution

Range. Mexico, Central America, northern South America, tropical Africa; Cuba, Jamaica, Hispaniola (Haiti and Dominican Republic), Puerto Rico, Guadeloupe, St. Lucia, Barbados; usually growing on rotten logs and less often on limestone or the bases of trees, in moist forests, from near sea level to ca. 1200 m.

Mexico North America| Central America| Brazil South America| Colombia South America| French Guiana South America| Ecuador South America| Guyana South America| Peru South America| Suriname South America| Venezuela South America| Africa| Cuba South America| Jamaica South America| Haiti South America| Dominican Republic South America| Puerto Rico South America| Guadeloupe South America| Saint Lucia South America| Barbados South America|