Plants dark green to brownish, somewhat glossy, tightly affixed to substratum. Stems 0.5-1 mm, erect, strongly radiculose. Leaves 0.5-5 mm, and somewhat crisped when dry, apex acute, the most proximal leaves reduced, laminal cells smooth, margins entire. Perichaetial leaves with smooth awn, 9-12 mm, lamina at awn base lacerate but not membranaceous. Capsule narrowly ovoid, 2-3 mm, stomata absent, mature capsules sheathed in penicellate perichaetium, awns extending more than twice the length of the immersed capsule. Spores 9-12 µm.
6. Diphyscium mucronifolium Mitt. in Dozy & Molk. 卷叶短颈藓 juan ye duan jing xian Bryol. Jav. 1: 35. Pl. 26. 1855. Webera mucronifolia (Mitt.) Broth., Nat. Pflanzenfam. I(3): 664. 1904. Type: Borneo. Labuan, Motley 4 (holotype NY). Diphyscium involutum Mitt., J. Proc. Linn. Soc., Bot., Suppl. 1: 149. 1859. Webera involuta (Mitt.) Broth., Nat. Pflanzenfam. I(3): 664. 1904. Plants small to medium-sized, 5–24 mm high, often in clumps. Stems usually simple, rarely branched; in stem cross section a central strand present. Leaves curled when dry, erect-spreading when moist, 3–6 mm × 0.3–1.0 mm, oblong-lanceolate to ligulate, acute to broadly acute, mucronate to apiculate at apex; leaf margins entire throughout, 2–4 cells thick in cross section; costa percurrent or shortly excurrent, with two stereid bands; leaf cells unistratose at base, bistratose above; median cells rounded to quadrate, 5–12 µm in diameter, smooth; basal cells rectangular, 15–50 µm × 4–10 µm, hyaline, smooth. Axillary hairs 5–15 cells long. Dioicous. Male plants usually smaller than female plants. Perichaetia terminal; perichaetial leaves lanceolate, awn excurrent, smooth; margins dissected or laciniate above. Setae short, to 0.3 mm long; capsules oblong-ovoid, obliquely asymmetric, 3–5 mm × 1.0–2.5 mm, abruptly narrowed at base and mouth; exothecial cells collenchymatous; stomata absent; annuli well differentiated, consisting of 1–3 rows of thick-walled cells; opercula conic, to 1 mm long, obtuse; peristome present. Calyptrae conic, smooth. Spores spherical, 8–14 µm in diameter, papillose.