Diplazium simplicivenium Holttum Biosystematic Study Of The Fern Genus Diplazium In West Malesia

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53. Diplazium simplicivenium Holttum

Diplazium simplicivenium Holttum, Gard. Bull. S.S. 11: 100, 101. f.6. 1940. –Athyrium simplicivenium Holtt. Holttum, Fl. Malaya 2: 573. f. 340. 1966. ---TYPE: Malay Peninsula, Pahang, Frasser’s, R.E. Holttum 36507 holotype, SING. Rhizome short, erect. Stipe 100 cm or more long, 15 mm thick, rough near base, fallen scales at base; scales 2 cm long or more, 1-2 mm wide near base, dark brown, margin toothed, teeth simple not forked. Lamina bipinnate, 55-150 cm long, 50-100 cm wide, or larger; pinnae c.15 cm apart, oblique; 45-66 cm long, 17-24 cm wide, free pinnules 15-20 pairs below the lobed apex of pinna; largest pinnule stalked to 1.5 mm, 7.4-12 by 1.8-2.1 cm, upper pinnules sessile, base truncate, apex acuminate, margin lobed 15-¼ way towards costa; lobes 6-7 mm wide, slightly oblique; texture thin; veins distinct on both surface, upper surface hairy, pinnate, veinlets 4-5 pairs, all simple. Sori covered the basal 13-¾ or more of veinlets; indusia thin, firm, persistent. SPORE. Monolete, bilaterally symmetrical, heteropolar; polar outline elliptical, sides convex; equatorial longitudinal view plano-convex to concave- convex to plano-convex; equatorial transverse view, proximal face planar to concave, distal face hemispherical; perinate. E: 43.9950.6154.60±3.36, P: 23.3129.42 33.78±2.79. Laesure: concealed by perine ridge. Perine: alate to costae alate, irregular envelope separated from exine surrounds the spore in irregular and in continuous or discontinuous anastomosing wing, forming a loose reticulation; lacunae large irregular polygons, occasionally with granulate deposite within; thin wingilike muri projected 3-8µm, terminating margins are almost entire. Exine: smooth regulate under SEM. ANATOMY. Vascular bundle form an uninterrupted U-shaped with an angle about 90º; base flat inward, slightly ridges outward, angle ridges, end distinctly ridges to form an angle 100º. CHROMOSOMES. 2n = 123 Cytotype: T.Ng. Praptosuwiryo 1386, BO. DISTRIBUTION. Malay Peninsula, Sumatra, Java, Thailand. 259 ECOLOGY. Found in shady mountain valleys and occasionally in exposed places by roadside drains. 400 – 1600 m. SPECIMENS EXAMINED. --- JAVA: Koorders 23538B; T.Ng. Praptosuwiryo 1136, 1139, 1351, 1341, 1342, 1348, 1349, 1351, 1371, 1449, 1519, 1521, 1523, 1526, 1530, 1761, . --- SUMATRA: T.Ng. Praptosuwiryo 2512; 2535. --- MALAY PENINSULA. Pahang: C.E. Carrr 22388; R.E. Holttum 36507 27-12-1939 HOLOTYPE, R.E. Holtum 21636. Perak: King 2214; King 2346. Selangor: H.L. Hume 9110.

54. Diplazium sorzogonense C. Presl