Palynology of Middle Tertiary lacustrine deposits

248 K. TAKAHASHI & U. lux
Botanical affinity: Unknown (Dicotyledonopsida).
Genus Favitricolporites Sah 1967.
Type species: Favitricolporites eminens Sah 1967.
Favitricolporites cf. retiformis Sah
PI. 31, figs. 4 a-b.
1967 Favitricolporites retiformis Sah, Mus. Roy. l'Afrique Cent. -Terv., Be1g. Ann., Ser.
in 8 0 , Sci. GeoI., no. 57, p. 87, pI. X, fig. 14.
Diagnostic characters: Trico1porate pollen grain. Figura suboblate or broadly triangular
in polar view. Three conspicuous co1pi with lalongate ora, enuimarginate, radially
symmetrical, converging towards the poles. Exine reticulate; lumina
1 + pm in
diameter; murus or tectum 1.5 pm high; endexine O. 7 pm thick.
Mesaurements: 25 X 22 pm in size.
Remarks: The specimen is quite referable to Favitricolporites retiformis Sah from the
Late Neogene of the Rusizi valley (Burundi).
Botanical affinity: Unknown.
Subturma Ptychopolyporines Naumova 1937 emend. Potonie 1960.
Genus Tetracolporites Couper 1953.
Type species: Tetracolporites oamaruensis Couper 1953.
Tetracolporites cf. kivuensis Sah
PI. 5, fig. 3.
1967 Tetracolporites kivuensis Sah, Mus. Roy. l'Afrique Cent., Terv., Be1g. Ann., Ser. in
8 0 , Sci. GeoI., no. 57, pp. 97-98, pI. IX, fig. 8 - 9; Fig. 31.
Diagnostic characters: Tetracolporate pollen of quadrangular contour and straight or
slightly convex sides in polar sight. Four fairly long colpi with distinctly lalongate
ora. Exine two-layered, 4 pm thick, smooth.
Measurements: 68 X 67 pm in equatorial diameter.
Previous record: Burundi (Africa): Late Neogene.
Remarks: The only specimen observed is a large species of the genus Tetracolporites
Couper 1953 which closely resembles T. kivuensis Sah from the Late Neogene of
Burundi.
Botanical affinity: Unknown (? Guttiferae).