Desmids from Thailand and Malaysia

32 M. HIRANO
L. 28 ym, B. 26.4 ptm I. 8 ptm. Cells hexagonal in outline, a little longer than the
breadth, deeply constricted, sinus narrowly linear; semicells subtrapeziform, apex almost
straight, apical angles obtuse with a denticulation, lateral margin slightly convex and
with 3 marginal teeth, inner part of a semicell with a pair of large granules just below
the apex; with small granules irregularly disposed within the lateral margin and in some
specimens these small granules somewhat arcuately disposed. The size of the specimens
examined is smaller than the dimension given by Prescott et al. St. 53. Europe,
N.America. New to Thailand.
54. C iavanicum Nordst. var. iavanicum
Hirano 1957, Contr. Biol. Lab. Kyoto Univ. 4, 118, Pl.21, f.2; Krieger & Gerloff
1962, Gatt. Cosm. 1,88, Pl.19, f.14.
L. 114 ptm, B. 66 ptm, I. 48.5 Ltm. Sts. 44,51. Indonesia (Java, Sumatra), Ceylon, In-
dia, Australia.
54a. var. elongatum Krieger&Gerloff Pl.15, f.1.
Krieger & Gerloff 1962, Gatt. Cosm. 1, 88, Pl.19, f.15.
L. 163-198 Ltm, B. 77-88 xtm, I. 42-4Zl xtm. Sts. 21,25,26,43,51. Australia. New to
Thailand.
55. C. Iaeve Rabenh. var. messikommeri Croasd.
Prescott et al. 1981, 2:3, 168, Pl.293, f.21,22.
L. 18.5 ptm, B. 12.3 ptm, I. 4.5 ptm. St. 31. Europe. New to Thailand.
56. C. tunatum Wolle var. orientale Scott&Prescott Pl.17, f.7,8.
Scott & Prescott 1961, Hydrobiol. 17, 60, Pl.32, f.5.
L. 17-20.6 ptm, B. 22-26 "m, I. 8 gm. Sts. 3,39. Indonesia (Borneo). New to Thai-
land.
57. C. lundellii Delp. f. crassangulatum Scott&Prescott Pl.14, f.6.
Scott & Prescott 1961, 61., Pl.25, f.10.
L. 49-70.4 um, B. 48.4-70.4 ptm, I. 21-33 ptm. Cells as long as the breadth,
deeply constricted, sinus open outward but acuminate at the extremity; semicells irregu-
lar rhomboidal, lateral angles somewhat acutely rounded and thickened. Sts. 23,32,43.
Indonesia (Java). New to Thailand.
57a. var. circutare (Reinsch) Krieger Pl.14, f.5.
Krieger 1932, 178, Pl.9, f.21; Scott & Prescott 1961, Pl.25, f.7.
L 54-70 ptm, B. 44-57 ptm, I. 16.7-18.7 #m, Sts. 20,25,32,43,47,51,53. Indonesia
(Sumatra, Bali). New to Thailand.
57b. var. ellipticum W.West Pl.15, f.2.
Krieger 1932, 178, Pl.9, f.20; Scott & Prescott 1961, 61, Pl.25, f.8; Prescott et al.
1981, 2:3, 179, Pl.160, f.7.
L. 55-60 ptm, B. 42-48.5 ptm, I. 11-15 ptm. Sts. 31,44. Indonesia (Java), Japan,
Europe, Australia, New Zealand. New to Thailand.