Leptophascum leptophyllum (Müll.Hal.) J.Guerra & M.J.Cano.

Taha, Mai A., Shabbara, Hanaa M. & Aseeri, Manal M., 2020, New Pottiaceae genera to the moss flora of Saudi Arabia and the Arabian Peninsula, Cryptogamie, Bryologie 20 (1), pp. 1-9 : 4-8

Leptophascum leptophyllum (Müll.Hal.) J.Guerra & M.J.Cano.

( Fig. 3 )

In Journal oF Bryology 22: 92 (2000). — Chenia leptophylla (Müll. Hal.) R.H.Zander , Bulletin oF the Buffalo Society oF Natural Sciences 32: 258 (1993).

Phascum leptophyllum Müll.Hal. , Flora 71: 6 (1888).

Physcomitrium rhizophyllum (Sakurai) , Botanical Magazine, Tokyo 52: 469 (1938).

Tortula rhizophylla (Sakurai) Z.Iwats. & K.Saito , Miscellanea Bryologica et Lichenologica 6: 59 (1972).

Tortula evanescens Broth., Proceedings oF the Linnean Society oF New South Wales 41: 582 (1916).

SPECIMEN EXAMINED. — Saudi Arabia. Asir region, Bariq governorate, Athrb mountain; 18°57’860’’N, 41°59’947’’E; 1232 m a.s.l.; grow on soil between the rocks of high mountains around it short shrubs; soil thickness 1.3 cm; slope slop; 29.X.2011, 27.I.2012,

A B F C D E G H J I

26.IV.2012, 29.VI.2012; air moisture 57, 56, 30, 35 respectively; leg. Manal Aseeri; 171Ma-d (CAIA).

DISTRIBUTION. — In Africa; Botswana, Canary Islands, Cape Verde, Kenya, Lesotho, Malawi, Mauritania, South Africa, Tanzania, Zimbabwe, in Asia; China: Yuannan, India, Japan, in Australia; New Zealand, in Europe; Azores, France, Germany, Italy, Madeira, Reunion, Portugal, Sardinia, Spain, in North America; Hawaiian Islands, United Kingdom, United States: Alabama; louisiana; New Mexico and in South America; Bolivia, Brazil, Chile, Ecuador, Paraguay ( Magill 1981; Arts & Sollman 1991; Crum & Eckel 1994; Lüth 2006; O’Shea 2006; Ros et al. 2013; www.tropicos.org 2019). New to the Arabian Peninsula

FLORISTIC ELEMENT. — Sub-cosmopolitan element.

DESCRIPTION

Plants

Green above, yellowish brown below, up to 5-8 (-9) mm long.

Stem

Branched or simple, oval to round in cross section, central strand absent, sclerodermis more or less developed.

Leaves

Appressed when dry, patent to open spreading with reflex apex when moist, obovate to spathulate, 1.3-1.7 mm long,

0.6-1 mm wide; apex acute to acuminate; margins plane usually crenulate, rarely serrate above, entire below; costa excurrent in short reflexed apiculus, stereid bands absent, with two guide cells in one layer; rhizoids shown from the back of the costa at leaf tips or along the leaf; upper lamina cells hexagonal, quadrate to short rectangular, incrassate, usually bulging on both surface, smooth, (15-) 20-25 µm long × 20-25 µm wide, smooth to bulging; basal lamina cells quadrate to short rectangular, 30-45 µm long × 20-25(-30) µm wide, smooth, thinner.

Propagules

Present on rhizoids, varied in shapes, multicellular, 40-80 µm in diameter.

Comment

Although the studied samples oF Leptophascum leptophyllum have the same range of leaf length, width and cell dimensions of those reported in most floras which described this taxon but the studied samples are taller than others in different areas (see: Crum & Anderson 1981; Magill 1981; Crum & Eckel 1994; Casas et al. 2006; Guerra et al. 2006). This may be attributed to high soil thickness which indicates more humidity and minerals for nutrition, beside its long duration in the region ( Kürschner 1984).

Figures

FIG. 3. — Leptophascum leptophyllum (Müll.Hal.) J.Guerra & M.J.Cano.: A, dry plant; B, wet plant; C, wet plant with rhizoids from the back of the costa at leaf tips or along the leaf; D-G, leaves;H, I, upper part of leaves; J, basal part of leaf; K, leaf cross section;L, stem cross section; M, rhizoidal propagule. Scale bars: A, 1 mm; B, 2 mm; C-G, 0.5 mm; H-J, 200 μm; K, 50 μm; L, M, 100 μm.