Thalli prostrate to suberect, in loosely or densely over-lying and intricately intertwining mats, rather light green, sometimes at maturity cell walls brown, opaque, with narrow, translucent margins; when dry, dark green; medium-sized to large, flat and flabellate above. Main axis dorsally plane to convex or slightly concave, often retaining its dominance, up to 27 mm long, 0.82-1.05 mm wide, apically rounded or slightly emarginate, eventually narrowing somewhat toward base, margins acute and unistratose for a width of 1 or 2 cells. Primary branches lateral, opposite or subopposite, 0.8-1.4 mm between successive ones, obliquely spreading, often overlapping, regularly pinnate with pinnae well developed, linear, distally with 2 or 3 paired pinnules, proximally with 4 or some-times even 5 paired pinnules, older, primary branches/pinnae up to 4.7 mm long, 590-650 µm wide, secondary branches/pinnules 0.75-1.6 mm long, 475-530 µm wide; from base of main axis or from apices of secondary branches, flagelliform branches sometimes produced. Dorsal epidermal cells in median part of apical segment of main axis, from above 5-7-sided, thin-walled, 105.0 x 25.0-37.5(-55.0) µm, subdorsal cells larger, 4-7-sided, 155.0-262.5 x 62.5-87.5 µm, subventral cells 170.0-237.5 x 60-85 µm, ventral epidermal cells 75-100 x 30.0-47.5 µm. Oil bodies rare or absent in dorsal and ventral epidermal cells, absent in up to 70% of marginal cells, present in internal cells, 1 or occasionally 2 per cell, 15-25 x 7.5-12.5 µm, subspherical, ellipsoidal or ovoid, with rounded ends, light brown, opaque, composed of numerous small globules. Margins of ultimate pinnules crenulate, outer cells smaller than intramarginal ones, from above 35-55 x 35.0-47.5 µm, ± subquadrate, with free walls bulging, intramarginal cells often obliquely orientated, polygonal, 72.5-100.0 x 52.5 µm, generally with 1 oil body each. Cross section of main axis at middle of ultimate segment plano-convex, or weakly concavo-convex, sometimes biconvex, 180 µm or 6(7) cell rows thick medianly, gradually tapering to unistratose margins, 1 or 2 cells wide, dorsal cells ± 27.5 µm thick, internal cells 37.5-50.0 µm thick; cross section of ultimate pinnule of primary branch, 100 µm or 3 or 4 cells thick medianly, pellucid, unistratose margins 2 or 3 cells wide. Mucilage papillae ventral, clustered at slightly emarginate apex of branch and in 2 spaced, acropetal rows, one on either side of midline, 300-360 µm between successive ones, reddish, club-shaped, 2-celled, above 45.0-62.5 x 25.0-32.5 µm, narrowing to inconspicuous basal cell, non-persistent. Rhizoids ventral on axes, sometimes also on pinnae, hyaline, 7.5-15.0 µm wide. Asexual reproduction by gemmae seemingly absent. Heteroicous, with male, female and rarely synoicous branches. Antheridial branches lateral, near base of primary pinnae, on one or both sides, occasionally at tips of secondary pinnules, oblong-linear, ± 700 µm long, 350 µm wide, in cross section 240 µm high, margins crenulate, with single, erect layer of swollen cells, 62.5-77.5 x 45-50 µm, bearing 5 or more pairs of antheridia, separated by unistratose cell layer; very rarely synoicous, basally with paired antheridia and apically with a few archegonia and short, laciniate cilia at tip. Gynoecial branches short, arising opposite base of primary branch on main axis, or toward base of main axis, sometimes toward middle of primary branch, between pinnae of 1st and 2nd orders, or between pinnae of 2nd and 3rd orders; paraphyses between and surrounding archegonia, up to 437.5 µm long, composed of single strands of 9 or more cells, joined end to end; sometimes up to 3 female branches in a sympodial cluster. Calyptra clavate, 3.2-5.3 x 0.7-1.1 mm, cross section of wall up to 225 µm or 4-6 cells thick, outermost row with scattered, thick-walled papillae, 65-90x 25-65 µm, extending upwards to apex, where they are grouped together, forming a corona. Seta ± 12 mm long, ± 280 µm wide, with 4 inner and 12 outer cell rows, i.e. 4 cells diam. Capsule ± cylindrical, 1200-1450 µm long, with 4 dehisced valves 320-375 µm or 12-15 cells wide, bistratose; cells of epidermal layer in external longitudinal view 100.0-142.5 x 25-35 µm, with straight or oblique end walls, and strong nodular thickenings; in cross section cells ± rectangular in shape, thickenings on adaxial radial walls sometimes extending slightly to outer tangential walls, mostly bands on one side of median wall alternating with those on the other side, i.e. forming a mirror image; inner cells in internal longitudinal view, 112.5-132.5 x 25-35 µm. Spores 15-20 µm diam., translucent. Finely scabrate. pinkish, with inner, irregularly shaped, green areas. Elaters 245-390 µm long, 10-14 µm wide, with single spiral band, tapering to unspiralled tips. Elaterophores at valve apices, in persistent tufts.
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