Palynology of Middle Tertiary lacustrine deposits

Palynology of Middle Tertiary lacustrine deposits 261
DiagnosIs: Tripoarte pollen garins. Figura circular to subcircular in outline. Exine
two-layered, weakly intrarugulate, O. 5-}' 5 ,urn thick; sculpture of exme
chagrenate or very finely punctate. Pores oval, 2 - 5 ,urn in diameter and provided
with both a weak annulus and costae pori, annulus 4 -
6 ,urn in diameter; one pore
is placed subequatorially.
Measurements: 19-28 ,urn X 19-21 ,urn in diameter.
Holotype: PI. 16, fig. 11; 23 X 21 ,urn in diameter; exine 0.5 ,urn thick, weakly intrarugulate;
surface of exine very finely punctate; annulus indistinct; pores 4 - 5
,urn in diameter; annulus 5 - 6,um in diameter; no. of specimen: los 1 - 4 (GN
5324) .
Name derivation: After the Federal Republic of Nigeria.
Remarks: The new species is somewhat alike Cricotriporites guianensis Leidelmeyer
from the Lower Eocene of British Guyana, although it has larger pores with less prominent
annuli.
Botanical affinity: Unknown.
Genus Trivestibulopollenites Pflug 1953.
Type species: Trivestibulopollenites butuloides Pflug 1953.
TrivestibulojJollenites sp.
PI. 16, figs.
9 a-b.
Description: Triporate pollen with a circular outline. Exine punctate, 1. 2 ,urn thick;
tectatum 0.5 ,urn thick; vestibulum developed but neither labrum nor annulus present.
Pores large and equatorially placed 3 - 4 ,urn in diameter.
Measurements: 28 X 27. 5 ,urn in equatorial diameter.
Remarks: The only specimen observed could not be identified specifically.
Botanical affinity: Unknown.
Genus Subtriporopollenites Pflug & Thomson 1953.
Type species: Subtriporopollenites anulatus Pflug & Thomson 1953.
Subtriporopollenites rotundiporifer n. sp.
PI. 16, figs. 1 - 2 .
Diagnosis: Triporate pollen of circular to oval outline. All pores except possibly one
are placed subequatorially, rather large, 4 - 7 ,urn in diameter. Exine two-layered,
1. 5- 2,urn thick, finely punctate to rugulate; ectexine intrabaculate; endexine