taxonID	type	description	language	source
88F3FD8C84375B1A876BB9D3797EDBA3.taxon	description	Figs 1, 2	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
88F3FD8C84375B1A876BB9D3797EDBA3.taxon	description	Description. Plants whitish-green or light green when fresh, yellowish-brown or light brown in dry condition; shoots 0.9 – 1.5 mm wide, usually scarcely and irregularly branched; branches Lejeunea - type. Stems 100 – 130 µm diameter, in transverse section with 9 (– 10) epidermal cells, surrounding 14 – 18 medullary cells, epidermal cells larger than medullary cells; cell walls pale brown or yellowish-brown, thick-walled, with triangular to bulging trigones, wall between trigones with thin to rather thick continuous thickenings; ventral merophyte 2 cells wide. Rhizoids at base of underleaves, few, tufted, usually hyaline, rhizoid disc not seen. Leaves closely imbricate, when moist, wide-spreading. Leaf lobes ovate to oblong-ovate, rarely falcate-ovate, 725 – 827 µm long, 544 – 617 µm wide, dorsal margin arched, ventral margin arched, margin entire to slightly crenulate with projecting cells, apex rounded, incurved. Lobe cells convex or weakly mammillose on dorsal side, thin-walled, with small to large triangular trigones, intermediate thickenings absent or occasionally seen in the basal cells; marginal cells rectangular or quadrate, 16.5 – 20.8 × 15.0 – 23.7 µm; median cells hexagonal to rounded, 22.5 – 37.0 × 21.5 – 38.5 µm, basal cells hexagonal to rectangular, 22.0 – 45.8 × 20.0 – 30.0 µm; ocelli rectangular to long hexagonal, 47 – 65 × 25 – 40 µm, (0 –) 1 – 5 per leaf lobe, basal, aggregated or isolated; oil bodies 3 – 5 per cell, long ellipsoidal to ovoid-cylindrical, 10.4 – 19.8 × 3.7 – 5.1 µm, Calypogeia - type, coarsely granular. Lobules small, ovate, 152 – 182 µm long, 120 – 135 µm wide, inflated, 0.2 – 0.3 of lobe length, free margin slightly involute, formed by 5 – 7 elongated cells, apex semicircular, apical tooth short, 1 - celled, obtuse, keel arched or nearly straight, lobule cells smooth or slightly convex. Underleaves imbricate, rarely contiguous, suborbicular to reniform, 287 – 330 µm long, 416 – 458 µm wide, wider than long, 3 – 5 of stem width, bifid to 1 / 2 of its length, lobes triangular with acute to obtuse apex, margin nearly entire or bluntly toothed at side, sinus V-shaped, bases rounded to cuneate, insertion line arched. Asexual reproduction by unmodified caducous leaves, lobules remain attached to the stem; or modified caducous leaves arising from upright flagelliform shoots on branch apices, smaller than ordinary leaves, margins usually with 1 - celled rhizoids. Sexuality autoicous. Androecia, gynoecia and sporophytes not seen.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
88F3FD8C84375B1A876BB9D3797EDBA3.taxon	distribution	Distribution, habitat and ecology. Pantropical (He 1999; Bastos et al. 2020). In Thailand, Pycnolejeunea contigua was found on tree trunks and branches in forest gaps, along forest margins or open habitats in coastal sand dune and tropical lowland forests, ranging from sea level to 480 m above sea level.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
5BFF33BB3C9E53E0A0F361966E331D60.taxon	description	Figs 3, 4	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
5BFF33BB3C9E53E0A0F361966E331D60.taxon	description	Description. Plants whitish-green or light green when fresh, yellowish-brown or light brown in dry condition; shoots 0.80 – 1.23 mm wide, usually scarcely and irregularly branched; branches Lejeunea - type. Stems 76 – 99 µm diameter, in transverse section with 8 – 11 epidermal cells, surrounding 9 – 14 medullary cells, epidermal cells larger than medullary cells; cell walls pale brown or yellowish-brown, thick-walled, with triangular to bulging trigones, wall between trigones with thin to rather thick continuous thickenings; ventral merophyte 2 cells wide. Rhizoids at base of underleaves, few, tufted, usually hyaline, rhizoid disc not seen. Leaves imbricate, wide-spreading when moist. Leaf lobes ovate, oblong-ovate to oblong, 468 – 680 µm long, 376 – 487 µm wide, dorsal margin broadly arched, ventral margin slightly to strongly arched, margin entire, apex rounded, incurved. Lobe cells convex or weakly mammillose on dorsal side, thin-walled, with small to large triangular trigones, intermediate thickenings absent or occasionally seen in the marginal and basal cells; marginal cells rectangular or quadrate, 18.0 – 22.8 × 11.3 – 23.0 µm, median cells hexagonal to rounded, 18.0 – 38.3 × 19 – 24.8 µm, basal cells hexagonal to rectangular, 25.0 – 41.5 × 20.0 – 26.0 µm; ocelli rectangular to long hexagonal, 39.5 – 63.5 × 21.0 – 36.5 µm, 4 – 15 per leaf lobe, suprabasal, commonly aggregated, confined from base to the ventral half of leaf lobe; oil bodies not seen. Lobules small, oblong, 132 – 178 µm long, 90 – 109 µm wide, inflated, 0.16 – 0.30 of lobe length, free margin slightly involute, formed by 5 – 7 (– 9) elongated cells, apex semicircular or rarely truncate, apical tooth short, 1 - celled, obtuse, keel arched or nearly straight, lobule cells smooth or slightly convex. Underleaves contiguous to imbricate, sometimes slightly remote, suborbicular to subreniform, 116 – 297 µm long, 206 – 363 µm wide, wider than long, ca. 3 of stem width, bifid to 1 / 3 – 1 / 2 of its length, lobes triangular with acute to obtuse apex, margin nearly entire or bluntly toothed at side, sinus V-shaped, bases rounded to cuneate, insertion line arched. Asexual reproduction by unmodified caducous leaves, lobule remain attached to the stem. Sexuality autoicous. Androecia on short branches, terminal or intercalary on branches, inflated, spicate, 407 – 663 µm long, 452 – 607 µm wide; bracts in 2 – 4 pairs, densely imbricate, isolobous; bracteole 1 – 2, restricted at the base of the branch, bifid. Gynoecia on short branches, with 1 (– 2) subfloral innovations; bracts in one pair, subequal in size, bract lobes obovate, 733 – 829 µm long, 286 – 563 µm wide, apex rounded, incurved, margin entire; ocelli 10 – 26 per lobe or numerous, aggregated from base to the middle of the lobe; bract lobules lingulate to narrowly oblong, 449 – 503 µm long, 126 – 157 µm wide, 0.5 – 0.8 of lobe length, ca. 2 / 3 of the bract-lobe area, apex acute to obtuse, keel slightly arched, short; bracteole shortly connate with the bracts at the base on one side or rarely on both sides, ovate to obovate, 479 – 602 µm long, 253 – 295 µm wide, apex usually emarginate or slightly bifid, lobe acute, margin entire; perianths obovate, ca. 0.5 emergent beyond bracts or sometimes almost entirely covered by bracts, 687 – 825 µm long, 380 – 488 µm wide, inflated, 5 - keeled, keels smooth or crenulate, apex usually truncate, beak short. Seta articulate. Capsule valves 4, broadly spreading after dehiscence. Elaters 30 per capsule, marginal elaters 22, upper ends attached to valve margins, inner elaters 8, usually rudimentary, both ends attached to valve surface. Spores not seen.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
5BFF33BB3C9E53E0A0F361966E331D60.taxon	distribution	Distribution, habitat and ecology. Tropical Asia, Australia and Oceanic Islands (He 1999; Yang and Lin 2011). In Thailand, Pycnolejeunea grandiocellata was found growing on tree trunks and branches in tropical lowland and submontane forests at 65 – 1200 m in elevation.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
89C57BD5CCB9501A856F0CE66FBC350A.taxon	description	Figs 5, 6, 7	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
89C57BD5CCB9501A856F0CE66FBC350A.taxon	diagnosis	Diagnosis. Pycnolejeunea zhuiana similar to P. papillosa, but differs in having 1 – 8 ocelli per leaf lobe, stems in transverse section composed of 9 – 11 epidermal cells surrounding 13 – 15 medullary cells and male bracteoles occurring along nearly the whole of the androecial branch length.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
89C57BD5CCB9501A856F0CE66FBC350A.taxon	description	Description. Plants whitish-green or light green when fresh, yellowish-brown or light brown in dry condition; shoots with leaves 0.71 – 1.32 mm wide; usually scarcely and irregularly branched; branches Lejeunea - type. Stems 117 – 132 µm diameter, in transverse section with 9 – 11 epidermal cells, surrounding 13 – 15 medullary cells, epidermal cells larger than medullary cells; cell walls pale brown or yellowish-brown, thick-walled, with triangular to bulging trigones, wall between trigones with thin to rather thick continuous thickenings; ventral merophyte 2 cells wide. Rhizoids at base of underleaves, few, tufted, usually hyaline, rhizoid disc not seen. Leaves imbricate, wide-spreading when moist. Leaf lobes ovate to oblong-ovate, occasionally falcate-ovate, 563 – 698 µm long, 429 – 512 µm wide, dorsal margin broadly arched, ventral margin slightly to strongly arched, margin entire or conspicuously crenulate with projecting cells, apex rounded, incurved. Lobe cells strongly mammillose on dorsal side, thin-walled, with small to large triangular trigones, intermediate thickenings absent or occasionally seen in the basal cells; marginal cells rectangular or quadrate, 12.5 – 20.5 × 12 – 18 µm, median cells hexagonal to rounded, 20.5 – 34.0 × 19.0 – 27.5 µm, basal cells hexagonal to rectangular, 22.0 – 42.6 × 20.0 – 30.5 µm; ocelli rectangular to long hexagonal, 35.0 – 61.7 × 23.6 – 36.0 µm, 1 – 8 per leaf lobe, basal, aggregated or isolated; oil bodies 2 – 5 per cell, long ellipsoidal to ovoid-cylindrical, 7.0 – 19.0 × 4.0 – 7.0 µm, Calypogeia - type, coarsely granular. Lobule small, ovate, 138 – 170 µm long, 125 – 156 µm wide, strongly inflated, 0.20 – 0.25 of lobe length, free margin slightly involute, formed by 5 – 6 elongated cells, apex semicircular, apical tooth short, obtuse; keel strongly arched, papillose; lobule cells strongly unipapillose. Underleaves contiguous to imbricate, sometimes slightly remote, suborbicular to subreniform, 234 – 316 µm long, 257 – 360 µm wide, wider than long, 3.0 – 3.5 of stem width, bifid to 1 / 3 – 1 / 2 of its length, lobes triangular with acute to obtuse apex, margin nearly entire, rarely bluntly toothed at side, sinus V-shaped, bases rounded to cuneate, insertion line arched. Asexual reproduction by unmodified caducous leaves, lobules remain attached to the stem. Sexuality autoicous. Androecia on short branches, terminal or intercalary on branches, inflated, spicate, 515 – 913 µm long, 408 – 561 µm wide; bracts in 3 – 5 pairs, densely imbricate, isolobous; bracteoles occurring nearly throughout androecium, composed of 2 (– 3) bilobed bracteoles restricted at the base of the branch and 1 – 2 reduced once above. Gynoecia on short branches, with 1 subfloral innovation; bracts in one pair, subequal in size, bract lobe obovate, 526 – 822 µm long, 317 – 488 µm wide, apex rounded, incurved, margin entire, ocelli 0 – 14 per lobe, isolated; bract lobules lingulate, narrowly oblong to ovate, 330 – 442 µm long, 132 – 258 µm wide, 0.6 – 0.8 of lobe length, ca. 2 / 3 of the bract-lobe area, apex acute to broadly obtuse, keel slightly arched, short; bracteole shortly connate with the bracts at the base on one side or rarely on both sides, ovate to obovate, 418 – 587 µm long, 276 – 409 µm wide, apex usually emarginate or slightly bifid, lobe acute, margin entire; perianths obovate, ca. 0.5 emergent beyond bracts or sometimes almost entirely covered by bracts, 664 – 921 µm long, 464 – 624 µm wide, inflated, 5 - keeled, keels crenulate or rough from projecting cells, apex usually truncate, beak short. Sporophytes not seen.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
89C57BD5CCB9501A856F0CE66FBC350A.taxon	etymology	Etymology. The specific epithet “ zhuiana ” honours Prof. Dr. Rui-Liang Zhu of East China Normal University, Shanghai (China), who has dedicated his entire life to the study of bryophytes, particularly in the taxonomy and systematics of Lejeuneaceae and the advancement of liverwort research in Asia.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
89C57BD5CCB9501A856F0CE66FBC350A.taxon	distribution	Distribution, habitat and ecology. Endemic to peninsular Thailand. So far known only from its type locality at Khao Ngon Nak Mountain, Hat Noppharat Thara - Mu Ko Phi Phi National Park, Krabi Province; however, it may also occur in other areas in southern Thailand with a similar vegetation type. Pycnolejeunea zhuiana was found growing on tree trunks in tropical lowland forests dominated by Baeckea frutescens L., Podocarpus neriifolius D. Don. and Syzygium antisepticum (Blume) Merr. & L. M. Perry., at elevations of 380 – 480 m. It is often found growing in association with Lejeunea flava (Sw.) Nees and P. contigua.	en	Promma, Chatchaba, Chantanaorrapint, Sahut (2025): The genus Pycnolejeunea (Lejeuneaceae, Marchantiophyta) in Thailand, with the description of Pycnolejeunea zhuiana. PhytoKeys 259: 145-160, DOI: 10.3897/phytokeys.259.156710
