Chryso-hypnum salleanum (Besch.) W.R.Buck

Authority

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

Family

Hypnaceae

Scientific Name

Chryso-hypnum salleanum (Besch.) W.R.Buck

Description

Species Description - Plants medium-sized, in ± stiff, dull, dark-green (when living) to golden-brown, often extensive, dense mats. Stems creeping to somewhat arched, wiry, to ca. 5 cm long, subpinnately branched, the branches mostly simple, slender, to ca. 1 cm long, mostly attenuate but sometimes blunt, densely foliate; in cross-section with 3-5 rows of small thick-walled cells surrounding larger thin-to firm-walled cells, central strand small, of small thin-walled cells; pseudoparaphyllia foliose, large; axillary hairs small, with 2(-3) short brown or hyaline basal cells and 1(-2) short brown or less often hyaline distal cells. Stipe leaves poorly differentiated, often eroded, broadly ovate, broadly inserted, short-acuminate; stem leaves wide-spreading to spreading dry or moist, broadly ovate to ovate-triangular, ca. 0.75 mm long (apparently larger in extralimital populations), abruptly broadly acuminate, ± concave, subplicate, especially when dry; margins serrulate throughout, plane; costa short and double; cells long-hexagonal, ca. 4:1, sparsely prorulose at upper ends at back, firm-walled, becoming porose toward the insertion; alar cells few and quadrate in extreme basal angles. Branch leaves erect-spreading to spreading dry or moist, ovate-lanceolate, 0.43-1 mm long (apparently larger in extralimital populations), gradually or rarely ± abruptly short-acuminate, the apex sometimes obtuse, ± concave, ± plicate; margins serrulate throughout, plane; costa short and double, sometimes to 1/4 the leaf length; cells long-hexagonal, ca. 4:1, sparsely to densely prorulose at upper ends at back, firm-walled, becoming longer and thicker-walled toward the insertion; alar cells few and quadrate in extreme basal angles. Asexual propagula none. Dioicous. Perichaetia and sporophytes not seen. [Inner perichaetial leaves acuminate into a long, reflexed acumen. Setae up to 3 cm long, reddish brown; capsules suberect to horizontal, oblong-cylindric, 2-3 mm long, 0.9-1.1 mm broad; operculum conicrostellate. Spores unknown. Nishimura, in litt]

Discussion

2. Chryso-hypnum salleanum (Besch.) W. R. Buck, comb. nov.; Hypnum salleanum Besch., Mém. Soc. Sci. Nat. Cherbourg 16: 253. 1872; Microthamnium salleanum (Besch.) Besch. ex Paris, Index Bryol. 811. 1897; Mittenothamnium salleanum (Besch.) Cardot, Rev. Bryol. 40: 21. 1913. Plate 132, figures 9-19 Discussion. Chryso-hypnum salleanum is characterized by broadly ovate, abruptly broad-acuminate stem leaves and ovate-lanceolate, gradually short-acuminate branch leaves. It is unlikely to be confused with C. diminutivum on the basis of areolation alone: the cells are long-hexagonal and only about four times longer than wide, rather than linear. To some the areolation may suggest a different genus, but for the time being, it is best used as a distinctive species marker. In aspect C. salleanum is superficially more like a Chryso-hypnum than a Mittenothamnium, due to the often turgid, densely foliate branches. Because of the very different aspect between C. salleanum and the other species in Mittenothamnium, a relationship there is not very satisfying. Thus, a transfer is made. However, the axillary hairs of C. salleanum are more like those of M. reptans and M. substriatum than those of C. diminutivum. More study is needed.

Distribution

Range. Mexico, Belize, Honduras; Cuba; all 4 Cuban collections seen (and most of the Mexican ones) grew on limestone, near streams, below 1000 m.

Mexico North America| Belize Central America| Honduras Central America| Cuba South America|