Palynology of Middle Tertiary lacustrine deposits

224 K. TAKAHASHI & U. jux
,urn) have an extrapunctate composition and are grouped in a distance of O. 5- 1 ,urn
parallel or almost meridionally to each other.
Measurements: 55 -70 ,urn in length.
31-50 ,urn in width.
Width / length ratio: 0.56-0.71.
Holotype: PI. 23, fig. l; 60 X 35 ,urn in size; outer layer l,um thick; ribs (striae)
with extrapunctate sculpture, extending from pole to pole, ca. l,um wide, ca. 0.5
,urn apart from each other; width/length ratio: 0.58; no. of specimen: Jos 1 - 4 (GN
5324) .
Name derivation: From the Federal Republic of Nigeria.
Remarks: The new species is similar to Striatopollis bellus Sah 0967, pI. V, figs. 15,
17) and Striatopollis (ai. Striatricolpites) catatumbus Gonzalez Guzman n. comb.
(Gonzalez Guzman, 1967, p. 30, pI. VIII, figs. 7 - 7 d), but differs from S. bellus
in having longer colpi and coarser ribs and from S. catatumbus in the more slender
shape and the coarse ribs.
Van der Hammen (956) described Tricolpites (Striatricolpites) virgulatus as a
subgenotype, indicating the pollen of recent Acer platanoides L. (Aceraceae) as type
specimen. Gonzalz Guzman (1967) raised this subgenus to generic rank by acquisition
of the nomenclatural type Striatricolpites catatumbus Gonzalez Guzman 0967, p.
30, pI. VIII, figs. 7 - 7 d). Nevertheless, the genus Styz'atricolpites was not validly
published.
Botanical affinity: Sah (967) suggested a solanaceous affinity,
but Solanaceae
pollen are furnished with three- (four) -colporate furrows. Germeraad, Hopping &
Muller (968) suggested closer affinity with the genus Crudia (Fabaceae).
Striatopollis variabilis n. sp.
PI. 24, figs. I - 3, 7, 9 - 10;
pI. 25, fig. I.
Diagnosis: Tricolpate pollen grains. Figura ellipsoidal or prolate with pointed or
hemispherical poles in equatorial view. Three colpi rather slender, radially symmetrical,
converging towards poles. Exine finely striate; striae in wavy or vortical
patterns arranged; columellae simple or with tectate and baculate muri,
high.
Measurements: 42-58 ,urn in length.
23-36 ,urn width.
1 -1. 5 ,urn
Width / length ratio: 0.54 -0.74
Holotype: PI. 24, fig. 2; 53 X 34 ,urn in size; exine finely striate, tectate or baculate,