Palynology of Middle Tertiary lacustrine deposits

204 K. TAKAHASHI & U. JUX
slightly chagrenate, very thin, less than 0.5 ,urn thick, one-layered, always strongly
folded.
Measurements: 15 - 19 ,urn X 13 - 17 JIm in diameter.
Holotype: PI. 7, fig. 6; size 19 X 17 JIm (diameter); exine more or less chagrenate,
thin, one-layered. No. of sample: Jos 1 - 2 (GN 5322).
Derivation of name: rugosus (lat.) = wrinkled.
Remarks: Such inaperturatepollen with these strongly folded exines were rarely encountered.
I. rugosus n. sp. is comparable with the smaller I. parvus Takahashi
from the Late Oligocene of St. Augustin (West-Germany) and the Miocene of West
Japan and Korea. The former differs from the latter in its delicate and strongly folded
exine.
Botancal affinity: Unknown.
lnaperturopolenites minimus n. sp.
PI. 7, figs. 17-23.
Diagnosis: Inaperturate pollen with approximately circular contour. Thin exine often
folded; more or less chagrenate or very fine punctate, 0.5- O. 8 JIm thick, onelayered.
Measurements: 12 - 17 JIm X 11 - 16 JIm in diameter.
Holotype: PI. 7, fig. 22; size 13 X 11 ,urn (diameter); exine slightly chagrenate, 0.7
,urn thick, one-layered, moderately folded; no. of sample: Jos 1 - 1 (GN 5321).
Name derivation: minimus Oat.) = the smallest.
Remarks: This new species is the smallest yet known among inaperturate pollen
grains with psilate exines. The difference in size separates from 1. parvus Takahashi
(963) .
Botanical affinity: Unknown.
Genus Psophosphaera Naumova 1937 ex Bolchovitina 1953.
Type species: Psophosphaera tenuis Naumova ex Bolchovitina 1953.
Psophosphaera pseudotsugoides Krutzsch
PI.
7, figs. 24a-b.
1971 Psophosphaera pseudotsugoides Krutzsch, Atlas, Lfg. VI, S. 192, Taf. 61, Fig. 1­
6.
1986 Psophosphaera psudotsugoides Krutzsch, Takahashi & lux, Bull. Fac. Liberal Arts,
Nagasaki Univ., Nat. Sci., Vol. 26, no. 2, pp. 77-78, Taf. 10, Fig. 17.