Desmids from Thailand and Malaysia

50 M. HIRANO
5a. var. mintLs W.West
West 1905, 2,53; Krieger 1937, 552, Pl.75, f.17.
L. 11.4 #m, B. 9.7 ptm, and I. 4 #m. St. 1. Europe, U.S.A.
5b. var. papilliferum Gutw. Pl.27, f.4.
Krieger 1937, 553, Pl.75, f.18-20.
L. 26.4 ptm, B. 20.7 ptm, and I. 4.5 #m. St. 40. Europe. New to Thailand.
6. Ebipartitum Krieger Pl.23, f.14; Pl.27,f.12.
Krieger 1932, Arch. Hydrobiol. Suppl.11, 211, Pl.20, f.16; Krieger 1937, 570, Pl.77,
f.28-30.
L. 22-24 ptm, B. 17.5-20 ptm, and I. 5.7-6.5 ptm. Cells small, approximately 1.3
times longer than the breadth, deeply constricted at the middle, sinus narrowly linear
and outer part slightly open; semicells 3-lobed, polar lobe transversely rectangular and
slightly dilated upward, apical angles with 2-3 minute denticulations, apex widely re-
tuse, lateral lobes rectangular, margin convex with 3 denticulations at and incide the
margin, with a ring of 5 granules in the centre of a semicell. Sts. 1,28,35,37. Indonesia
(Sumatra). New to Thailand.
7. E. boldtii Schmidle Pl.23,f.4,5.
Krieger 1937, Krypt. Pl. 13:1, 563, Pl.77, f.5-7.
L. 24 Ltm, B. 20 ptm, and I. 5.7 Ltm. Cells small, approximately 1.3 times longer
than the breadth, deeply constricted at the middle, sinus narrowly linear; semicells 3-
lobed, polar lobe transversely rectangular, apex retuse at the middle, apical angles with
a short spine, side of polar lobe convex, incision between polar and lateral lobes retuse,
lower lateral margin convex and divergent. The specimens examined from Thailand are
slightly different from the typical form of E. boldtii. This species resembles both E.
sibiricum f. fennica and E. sibiricum f. exsecta. However, it is different from these two
forms by the lack of granules or denticulations described by Gr6nblad 1921 (Pl.3, f.16-
19). It is also different from E. gayanum by a small size. Sts. 36,39. Europe. New to
Thailand.
8. E. ceylanicum (W.&G.S.West) Krieger Pl.25,f.2.
Krieger 1937, Krypt. Fl. 13:1, 627, Pl.90, f.16,17; Scott & Prescott 1961, 24, Pl.11,
f.3-5; Hirano 1967, Nature and Life Southeast Asia 5, 57.
L. 73.5 ptm, B. 66 ptm, and I. 13 "m. Cells fairly large, slightly longer than the
breadth, sinus narrowly linear; semicells 3-lobed, polar lobe obcuneate, lateral lobes
horizontal, polar and lateral lobes furnished with sharp denticulations, central part of a
semicell with a cycle of denticulations. St. 24. Ceylon, Indonesia (Sumatra, Borneo),
Cambodia, Japan. New to Thailand.
9. E. crameri Racib. PL25,f.3.
Krieger 1932, 211, Pl.20, f.12 (forma); Krieger 1937, 620, Pl.90, f.1-3; Ruzicka 1:2,
504, Pl.82, f.20-22.
L. 88 pt m, B. 53 pm, and I. 11 um. St. 26. Europe, Japan. New to Thailand.