Pleurozia subinflata (Austin) Austin (1874: 16)

Sukkharak, Phiangphak, 2017, A revision of the genus Pleurozia (Marchantiophyta: Pleuroziaceae) in Thailand and little known morphological features of the genus, Phytotaxa 309 (3), pp. 201-216 : 206-211

2. Pleurozia subinflata (Austin) Austin (1874: 16) .

Basionym:— Physiotium subinflatum Austin (1869: 224) . Type: U.S.A. Hawaii: Oahu, Mann & Brigham s.n. (lectotype, designated by Thiers 1993, MANCH; isolectotypes, BM, FH-general herb., FH-James herb., G, H, NY; syntypes, Sandwich Is., ex herb. Aust., Baldwin s.n., G, Baldwin 47, BM, MANCH, NY-3) ( Thiers 1993).

= Physiotium pacificum Carring. ex Gott. & Rabenh. in Rabenhorst & Gottsche (1877: -) ( Thiers 1993).

= Physiotium wilkesii Gott. & Jack in Jack (1886: 75), nom. inval. ( Thiers 1993).

= Physiotium acutifolium Jack (1886: 75) ( Thiers 1993).

= Pleurozia evoluta (Mitt.) Steph. in Schinz (1897: 843). Physiotium evolutum Mitt. in Seemann (1873: 407) ( Thiers 1993).

= Pleurozia microcarpa (Jack) Stephani (1910: 238) . Physiotiumm icrocarpum Jack (1886: 71) ( Thiers 1993).

= Eopleurozia giganteoides (Horik.) Inoue (1976: 181) . Pleurozia giganteoides Horikawa (1934: 229) ( Thiers 1993).

Description:—( Figs. 4−7 ). Plants autoicous ( Thiers 1993), pendent, prostrate stems dominant, sparsely branched, with stems bearing sterile gynoecia or fertile gynoecia scattered along main stems; up to 1.3 cm long, 0.4−4.5 mm wide. Simple leaves on bases of upright branches, ovate to orbicular, concave, 1.5−4.6 × 1.4−2.5 mm, apex acute to rounded, margins entire, base auriculate. Explanate-lobuled leaves dominant on main stem; ventral lobes ovate to lanceolate, 4.4−6.3 × 1.8−2.6 mm, strongly concave, apex acuminate, margins entire or with 1−2 teeth near apex, incurved, base auriculate; apical cells quadrate to rectangular, 36−83 × 36−50 μm, marginal cells quadrate to rectangular, 41−66 × 33−55 μm, median cells quadrate to rectangular, 55−83 × 36−47 μm, basal cells rectangular, 77−138 × 27−41 μm; dorsal lobules ovate to lanceolate, 1.7−3.3 × 0.30−0.5 mm, concave, apex acuminate, margins entire, incurved, base auriculate, basal flaps variable in shape and size; keel with appendages on both sides of stem, appendage margin with triangular tooth. Saccate-lobuled leaves restricted to innovations; ventral lobes ovate, 2−2.2 × 1−1.1 mm, strongly concave, apex acute to rounded, margins entire, incurved, base auriculate; cells similar in shape and size to those of ventral lobes of leaves with explanate lobuled leaves; dorsal lobules elliptical, 1.6−1.8 × 0.6−0.7 mm, aperture complex acinosa - type (subapical, basin oblong, lip discontinuous, overarching basin on proximal side); keel with appendages on both sides of stem. Androecia not seen. Fertile gynoecia terminal, bracts 6−7 × 3.5−3.8 mm, trilobed, lobes extending 1/3× bract length, lobes ovate, apices acuminate, margins laciniate; perianths oblong, 9−11 × 1.75−2.0 mm, plicate in the upper 1/3−1/2, mouth ciliate. Sterile gynoecia lateral; bracts 7−8 × 4−6 mm, trilobed, lobes extending 1/3× bract length, lobes ovate, apices acuminate, margins laciniate; perianths oblong, 12−13 × 2−2.6 mm, mouth entire.

Additional illustrations:— Jack (1886: Tab. VI. Figs. 1 −17 as Physiotium subinflatum ); Thiers (1993: Figs. 84– 94); Bai & Li (1998: Fig. 2 : 1–7).

Ecology:— 2500–2590 m; on twigs, branches, bark, in Sphagnum bogs, and in evergreen forests.

Representative specimens:— Chiang Mai. INTHANON MT.: summit region, 18°35’ N 98°30’ E, Touw 9798 ( BKF), Chantanaorrapint & Inuthai 316 ( PSU) ; Ang Ka, Thaithong 894 ( BCU), Printarakul 3629 (2 packets) ( CMUB), Sukkharak 5023, 5024, 5025, 5026, 5027 (Hb. Burapha Univ.) .

Distribution:— U.S.A. (Hawaii), Sri Lanka, China, Japan, Taiwan, Vietnam, Thailand ( Thiers 1993).

Taxonomic notes:— The outstanding characters of Pleurozia subinflata are (1) dominant explanate-lobuled leaves on main stem, (2) presence of appendages with one triangular tooth on the keel of the dorsal lobule, and (3) laciniate gynoecial bract margins. Pleurozia subinflata was reported in Thailand as P. giganteoides ( Lai et al. 2008) .

Figures

FIGURE 1. Pleurozia acinosa. A. Branch with saccate-lobuled leaves, dorsal view. B. Branch with saccate-lobuled leaves, ventral view. C. Saccate-lobuled leaves. D. Branch with simple leaves and gynoecium, dorsal view. E. Branch with simple leaves and gynoecium, ventral view. F. Simple leaves. [All from Touw 11765 (BKF)].

FIGURE 2. Pleurozia acinosa. A. Branch with sterile gynoecia, dorsal view. B. Branch with sterile gynoecia, ventral view. C. Bract of sterile perianth. D. Sterile perianth, dorsal view. E. Sterile perianth, ventral view. [All from Touw 11765 (BKF)].

FIGURE 4. Pleurozia subinflata. A. Branch with explanate-lobuled leaves, dorsal view: a = appendage.B. Branch with explanate-lobuled leaves, ventral view. C. Explanate-lobuled leaves: a = appendage. [All from Chantanaorrapint & Inuthai 316 (PSU)].

FIGURE 5. Pleurozia subinflata. A. Branch with saccate-lobuled leaves, dorsal view. B. Branch with saccate-lobuled leaves, ventral view. C. Saccate-lobuled leaves: a = appendage. D. Branch with sterile gynoecia, dorsal view. E. Branch with sterile gynoecia, ventral view. F. Simple leaves. [All from Chantanaorrapint & Inuthai 316 (PSU)].

FIGURE 6. Pleurozia subinflata. A. Fertile gynoecium, dorsal view. B. Fertile gynoecium, ventral view. C. Bract of fertile perianth, dorsal view. D. Bract of fertile perianth, ventral view. E. Fertile perianth, dorsal view. F. Fertile perianth, ventral view. G. Stertile gynoecium, dorsal view. H. Stertile gynoecium, ventral view. I. Bract of sterile perianth, dorsal view. J. Bract of sterile perianth, ventral view. K. Stertile perianth, dorsal view. L. Stertile perianth, ventral view [All from Chantanaorrapint & Inuthai 316 (PSU)].

FIGURE 7. Pleurozia subinflata. A. Apical cells of ventral lobe. B. Appendage of keel of dorsal lobule. C. Marginal cells of ventral lobe. D. Median cells of ventral lobe. E. Basal cells of ventral lobe. [All from Chantanaorrapint & Inuthai 316 (PSU)].