Schwetschkeopsis fabronia (Schwägr.) Broth.

Authority

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

Family

Myriniaceae

Scientific Name

Schwetschkeopsis fabronia (Schwägr.) Broth.

Description

Species Description - Plants small, in mostly ± lustrous, green to golden, soft, dense, flat, often extensive mats. Stems creeping, to ca. 3 cm long, but mostly ca. 1 cm, freely and irregularly branched, the branches horizontal, often attenuate, terete-foliate or ± complánate; in cross-section with 4-5 rows of small thick-walled cells surrounding larger thinner-walled cells, central strand none; pseudoparaphyllia folióse; axillary hairs with 1-2 short brown basal cells and a single somewhat elongate hyaline distal cell. Stem and branch leaves similar, crowded, appressed when dry, erect to erect-spreading when moist, sometimes ± complanate, ovate-lanceolate, 0.5-0.7 mm long, ± abruptly acuminate, concave, sometimes short-decurrent; margins serrulate almost to base, plane; costa none; cells long-hexagonal, (2-)3-7:1, prorulose at upper cell ends at back, firm-walled; alar cells quadrate to subquadrate to oblate in sizable groups, extending up the margins by 15-20 cells, not or barely reaching midinsertion, decurrencies, when present, of 2-3 elongate cells. Asexual propagula none. Phyllodioicous. [Sporophytes not known from the West Indies; description based on Florida material.] Perichaetial leaves sheathing, lanceolate to long-triangular, gradually acuminate; margins serrulate above, subentire below, plane; costa none; cells smooth or obscurely prorulose, short-linear, thick-walled and porose in the acumen, becoming broader, short and nonporose below, quadrate all across the insertion. Setae elongate, smooth, reddish, ca. 1 cm long, flexuose; capsules erect to suberect, symmetric, cylindric, yellowish, 1-1.25 mm long; exothecial cells short-rectangular, thin-walled; annulus not differentiated; operculum not seen; exostome teeth narrowly triangular, shouldered, bordered, on the front surface with a zig-zag median line, cross-striolate below, papillose above, trabeculate at back; endostome finely papillose throughout, with a moderately high basal membrane, segments keeled, perforate, ca. as long as the teeth, cilia none. Spores spherical, finely papillose, 16-20 µm diam. Calyptrae not seen.

Discussion

1. Schwetschkeopsis fabronia (Schwãgr.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 878. 1907; Helicodontium fabronia Schwãgr., Sp. Musc. Frond. Suppl. 3(2): 294. 1830; Leskea fabronia Hook, ex Schwãgr., Sp. Musc. Frond. Suppl. 3(2): 294. 1830, nom. nud. in syn.; Hypnum fabronia (Schwãgr.) Harv., J. Bot. (Hooker) 2: 17. 1840; Stereodon fabronia (Schwãgr.) Mitt., J. Proc. Linn. Soc., Bot. Suppl. 1: 99. 1859; Microthamnium fabronia (Schwãgr.) A. Jaeger, Ber. Thãtigk. St. Gallischen Naturwiss. Ges. 1876-77: 426. 1878. Plate 108, figures 8-13 Leskea denticulata Sulk, Musci Allegh. 19(no. 62). 1845 [1846]; Hypnum fabroniaefolium Müll. Hal., Syn. Musc. Frond. 2: 271. 1851, non H. denticulatum Hedw., Sp. Musc. Frond. 237. 1801 [= Plagiothec-ium denticulatum (Hedw.) Schimp.]; Schwetschkeopsis denticulata (Sull.) Broth, in Engl. & Prantl, Nat. Pflanzenfam. 1(3): 878. 1907. Discussion. Schwetschkeopsis fabronia is characterized by small plants in mostly dense, extensive mats. The mostly ecostate leaves with prorulose upper cells and well-developed alar cells are diagnostic. Plants are rarely fertile but, when present, capsules are mostly erect. The illustration of sporophytes in Crum and Anderson (1981: 835, figs. 399C, F, G) is in error, and probably drawn from another genus. However, Sullivant (1864, tab. 78) provided a handsome, accurate drawing. Iwatsuki and Sharp (1967), in a bryogeographical study of the mosses of eastern Asia and eastern North America, were the first to document that Asian and American material of Schwetschkeopsis is the same species. The species has not previously been reported from the West Indies, and my report is based on two collections (Acuña 405 and Pócs & Borhidi 9010/ AH, both at NY).

Distribution

Range. Eastern United States, Nepal, Japan, Korea, northeastern China; Cuba; growing on tree trunks, in Cuba in humid forests, at 700-1000 m, in Florida in open forests at low elevations.

United States of America North America| Nepal Asia| Japan Asia| North Korea Asia| South Korea Asia| China Asia| Cuba South America|