Palynology of Middle Tertiary lacustrine deposits

212 K. TAKAHASHI & U. jux
Holotype: PI. 6, fig. 3; 79 X 39 pm in size; sculpture of exine psilate-scabrate in optical
section, granulate or reticulate (lumina 0.5 ,urn) in surface view; columellae
digitate, 1. 5 pm long on the sides,
3 - 4 pm long in apocolpia; width / length ratio:
0.49; no. of specimen: los I - 3 (GN 5323).
Name derivation: From the shape of the pollen, lanceolatus (lat.)
= like the head of
a lance.
Remarks: Apparently the los specimens belong to the genus Perfotricolpites Gonzalez
Guzman 1967, but relationship on specific level is quite uncertain. They obviously
bear little resemblance to Perfotricolpites digitatus Gonzalez Guzman (1967, p. 34,
pI. VI, figs. I-If) from the Early-Middle Eocene in Columbia.
Botanical affinity: Refering to the genus Merremia (Convolvulaceae) is conceivably
possible.
Perfotricolpites nigerianus n. sp.
PI. 6, figs. I - 2 .
Diagnosis: Tricolpate pollen of ellipsoidal or fusiform shape exhibiting rounded
apices in equatorial view. Three long and radially symmetrical colpi are rather conspicuous,
as they gape widely ( 1 -1. 5 pm wide) and extend almost parallel to the
poles. Ectexine thicker than endexine. Endexine 1 pm thick; columellae digitate in
apocolpia (5.5-11 ,urn thick); intrabaculate on the sides (2.5 pm thick). Sculpture
of exine of psilate-scabrate structure in optical section, however, granulate or
reticulate on the outer surface; granule or lumina ca. l,um (or less) in diameter.
Areolate ornamentation is either irregularly arranged within the mesocolpia or in a
row along the inner borders of the colpi (3 - 6 pm in diameter) .
Measurements: 95-100 pm in length.
47-55 pm in width,
Width / length ratio: 0.47-0.58.
Holotype: PI. 6, figs. I a-c; 100 X 47 pm in size; columellae digitate, 9 -11 pm
long in the polar areas; intrabaculate, 2.5 pm thick on the sides. Sculpture of exine
psilate. Areolae lined up along the borders of the colpi, however rather irregularly
within the mesocolpia, 3 - 6 pm in diameter. No. of specimen: los 1 - 3 (GN
5323) .
Derivation of name: From the Federal Republic of Nigeria.
Remarks: A comparable species is unknown to the authors. Although the genus
Areolipollis displays an areolate ornamentation, it is structurally a two colporate to
two colpate (?) pollen grain.
Botanical affinity: Unknown.