Plagiochila cuspidata Steph., Sp. Hepat.

Majumdar, Shuvadeep, 2021, Comments on the typification of Plagiochila cuspidata with a note on the morphology of Plagiochila cuspidata and Plagiochila parvifolia (Plagiochilaceae: Marchantiophyta), Phytotaxa 489 (1), pp. 94-98 : 97

Plagiochila cuspidata Steph., Sp. Hepat. 6: 144. 1918.

Plants 8–22 mm long, 2.0– 2.6 mm wide including leaves, light brown, rarely branched; branches lateral intercalary, in the older portion of shoot (only a single branched vegetative shoot is observed in the population). Stem broadly elliptical in outline in transverse section, 170–190 × 240–260 um, 15–20 cells across diameter, cortical cells in 2–3 cell layers, more or less rectangulate–subquadrate or polygonal, 5.0–12.5 × 7.5–17.5 um, thick-walled, reddish brown; medullary cells rectangulate–subquadrate or polygonal, 12.5–25.0 × 17.5–30.0 um thin-walled, hyaline; dorsal and ventral stem surfaces almost completely hidden. Paraphyllia absent. Rhizoids few, present on aerial shoots, scanty, also present at the branches. Leaves closely imbricate, horizontally spreading, moderately fragmenting, broad, triangular-ovate, 1.3–1.4 mm long, 1.3–1.4 (-1.6) mm wide at base, dorsal margin almost straight, entire, base moderately decurrent, apex truncate or rounded, teeth restricted towards the apex of leaves, ventral margin strongly ampliate at base, closely appressed to opposite leaf bases, base short-decurrent, margin with small undulation; teeth 0–5 (-6) per leaf, 1–5 (-7) cells long, 1–3 cells wide at base, 1–3 (-5) cells uniseriate towards apex, terminal leaf cells acute–acuminate, 25–35 (-40) × 7.5–20.0 µm, length:breadth ratio 1.7–3.3:1; apical and subapical leaf cells oval–subquadrate, 17.5–25.0 × 17.5–30.0 µm; median leaf cells oval–ellipsoidal, 25.0–37.5 × 20.0–27.5 µm, basal leaf cells slightly elongated, 35.0– 52.5 × 17.5–30.0 um, thin-walled, trigones large, nodulose, bulging, interrupted by intermediate thickenings, surface smooth. Underleaves vestigial.Asexual reproduction by fragmenting leaves, often breaking off at distal quarter. Fertile plants absent.