11. Calymperes tenerum C. Müll., Linnaea. 37:174. 1872.
Plants small, pale, compact, in low turfs. Stems short, forked; rhizoids brown. Leaves only somewhat dimorphic, 2–3 mm long, not much contorted when dry, usually secund, straight and erect-spreading when wet, vegetative leaves oblong, gemmiferous leaves oblong or acuminate, axillary hairs inconspicuous; costa excurrent in gemmiferous leaves; cells of upper laminae isodiametric, smooth to unipapillose abaxially, mammillose-papillose adaxially; margins unistratose or slightly thickened, entire throughout; teniolae lacking; cancellinae narrow, typically truncate distally. Gemmae common, in pale spherical clusters all around on tip of excurrent costa. Sporophytes not seen.
Type. India: Bengalia, Calcutta, S. Kurz s.n. (isotype BM).
Chinese specimens examined: GUANGDONG: Xi-sha Island, S.-H. Li 474 (IBSC, LAF). HAINAN: Chang-jiang Co., C. Gao et al. 3112 (IBSC, IFP, LAF). TAIWAN: Botel Tobago, Schwabe 90 (NICH); Kao-hsiung Co., C.-C. Chuang 1147 (UBC).
Habitat: rare; on tree trunks in humid forests at low elevations; Distribution: often very common and abundant in much of the Palaeotropics but very rare in the neotropics.
This little moss is very well marked by its lack of teniolae, pale spherical clusters of gemmae all around on the tips of the excurrent costa of gemmiferous leaves, and distally truncate cancellinae. See discussion under C. graeffeanum for differentiation from that species, which is the only other Chinese Calymperes with which it could be confused.
Illustrations: Reese & P.-J. Lin 1991 (figs. 53–58).