Koponobryum papillosum Printarakul & Chantanaorr., 2021

Printarakul, Narin, Jampeetong, Arunothai, Pongkawong, Udon, Sukkharak, Phiangphak, Kraichak, Ekaphan, Adulkittichai, Kanonrat & Chantanaorrapint, Sahut, 2021, Koponobryum papillosum Printarakul & Chantanaorr., sp. nov. (Pottiaceae, Bryophyta), a new moss species from northern Thailand, Cryptogamie, Bryologie 20 (9), pp. 143-148 : 144-148

Koponobryum papillosum Printarakul & Chantanaorr. , sp. nov.

( Figs 1-3 )

DIAGNOSIS. — Similar to K. bengalense (Gangulee) Arts , but differing in autoicous plants, papillose spores, and axillary hairs consisting of one short basal cell and 1-4(5) longer upper cells.

TYPE. — Thailand. Chiang Mai Province: Mae Rim District, Doi Suthep-Pui National Park, Mae Sa Falls, 18°54’25.7”N, 98°53’46.6”E, c. 420 m elev., 19.VII.2020, N. Printarakul & K. Adulkittichai 19072020_1 (holo-, CMUB!; iso-, BKF!, PSU!).

ADDITIONAL SPECIMENS EXAMINED. — Thailand. Chiang Mai Province: Mae Rim District, Doi Suthep-Pui National Park, Mae

Sa Falls, c. 420 m elev., on soil under granitic rock, 18°54’25.7”N, 98°53’46.60”E, 4.X.2013, N. Printarakul 6444 ( CMUB); Chiang Dao District, Doi Chang Dao Wildlife Sanctuary, Huay Sob On forest protection unit, c. 710 m elev., on soil under calcareous rocks, 19°21’33.7”N, 98°43’07.5”E, 19.VIII.2017, N. Printarakul 7280 ( CMUB, PSU). Lamphun Province: Sri Bua Ban District, the Hariphuchai Education Centre of Chiang Mai University, c. 500 m elev., on soil under calcareous-sandstones, 18°32’17.33”N, 99°07’28.10”E, 22.VIII.2020, N. Printarakul, A. Jampeetong & U. ongkawong 22082020_15 ( CMUB).

ETYMOLOGY. — The specific epithet “ papillosum ” refers to the papillose spores.

HABITAT AND DISTRIBUTION. — Koponobryum papillosum Printarakul & Chantanaorr. , sp. nov. is currently known only from northern Thailand. It grows on disturbed soils on a degraded calcareous substrate, sandstones and granitic rocks in deciduous, dipterocarp-oak, and also in mixed evergreen-deciduous seasonal forests at elevation of 420- 710 m.

CONSERVATION STATUS. — IUCN (2012) category Least concern (LC). Although only three locations were found in Thailand, they are within the well-protected areas. Therefore, this species is not under immediate threat.

DESCRIPTION

Plants

Up to 17 mm high (including sporophytes), pale to light green, forming loose turfs.

Rhizoids

Reddish to pale brown, clustered at stem base.

Stems

Erect, unbranched, dark green to reddish brown, in cross section 8-10 layers of cells across, 120-150 µm in diameter; outer cortical cells somewhat smaller with moderately thick-walled, inner cortical cells larger with thicker walls; central stand consisting of smaller and thin-walled cells.

Axillary hairs

Filiform, uniseriate, 2-5(-6) cells long, the basal cell shortest and yellowish to pale brown, the upper cells distinctly longer and colorless.

Leaves

Contorted when dry, erecto-patent to spreading when moist; lanceolate to oblong-lanceolate, 1.1-1.5 × 0.3-0.4 mm; apex acute to acuminate; base slightly decurrent; margins plane above, slightly revolute below, bordered throughout by 1-3 rows of elongate cells, remotely serrulate to denticulate above the midleaf; costa single, stout, short excurrent, ventral and dorsal surfaces smooth, not prominently bulging; costa cross section at midleaf semicircular to elliptic, with one stereid band; lamina unistratose, orange to red with KOH; upper laminal cells subquadrangular, polygonal to rounded-hexagonal, (20-) 25-30 µm in diameter, with a central papilla on both sides, firm to slightly thick-walled; basal marginal cells elongate rectangular, (35-) 40-80 × 12.5-15 µm wide, thin-walled; basal juxtacostal cells broader, rectangular, (37.5-)50-90 × 25-35 µm, thin-walled.

Asexual reproduction

Not seen.

Figures

FIG. 1. — Koponobryum papillosum Printarakul & Chantanaorr.,sp. nov.: A, plants in natural habitat;B, sporophyte bearing plants;C, leaves;D, leaf apex;E, upper laminal cells and marginal cells; F, leaf bases; G, sporophyte; H, capsule; I, peristome and spores; J, calyptra. Photos by N. Printarakul. All from N. Printarakul & K. Adulkittichai 19072020_1 (CMUB). Scales bars: A, G, H, 1 mm; B, 3 mm; C, J, 0.5 mm; D-F, I, 50 µm.

FIG. 2. – Koponobryum papillosum Printarakul & Chantanaorr., sp. nov.: A, KOH color reaction of plant; B, cross section of stem; C, vegetative leaf; D-G, cross sections of leaf from upper to base; H, perichaetium and perigonium; I-L, perichaetial leaves; M-O, perigonial leaves; P, axillary hair. Photos by N. Printarakul. All from N. Printarakul & K. Adulkittichai 19072020_1 (CMUB). Scale bars: A, 1 mm; B, D-G, P, 25 µm; C, H-O, 0.5 mm.

FIG. 3. – Koponobryum papillosum Printarakul & Chantanaorr.,sp.nov.:A, plants with sporophytes;B, cross section of stem;C, variations of axillary hairs;D, leaves; E, cross section of midleaf; F, leaf apex; G, leaf base; H, peristome (SEM); I, spore (SEM). A-G. Drawn by N. Printarakul. All from N. Printarakul & K. Adulkittichai 19072020_1 (CMUB). Scale bars: A, 1 mm; B, C, F, G, 50 µm; D, 0.5 mm; E, 25 µm; H, 10 µm; I, 1 µm.