Middle Miocene palynoflora of the Legnica lignite deposit complex ...

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in southern Africa and Europe, on the Atlantic
islands, in Asia Minor and Syria. The genus
Rhododendron (about 500–600 species) grows
in East Asia, North America, Caucasus and
Malaysia. Arbutus unedo is an evergreen tree
characteristic for the Mediterranean makhia
(Krüssmann 1976, 1977, 1978).
Familiae CLETHRACEAE,
CYRILLACEAE
(111) Tricolporopollenites exactus (Potonié
1931) Grabowska in Ziembińska-Tworzydło
et al. 1994
Pl. 13, fi g. 14
1931b Pollenites exactus n. sp., Potonié, p. 26, pl. 1,
fi g. V49b.
1953 Tricolporopollenites megaexactus (Potonié) n.
comb. subsp. exactus (Potonié) n. comb., Thomson
& Pfl ug, p. 101, pl. 12, fi gs 87–92.
1960 Cyrillaceaepollenites exactus (Potonié) n. comb.,
Potonié, p. 102.
1994b Tricolporopollenites exactus (Potonié) Grabowska
comb. nov.; Ziembińska-Tworzydło et al., p. 28,
pl. 16, fi gs 8–10.
R e m a r k s. This species occurs in the Eocene
to Miocene deposits. At Legnica these pollen
grains were encountered regularly, reaching
max. 20%.
(112) Tricolporopollenites megaexactus
(Potonié 1931) Thomson & Pfl ug 1953
Pl. 14, fi g. 1
1931b Pollenites megaexactus n. sp., Potonié, p. 26,
pl. 1, fi g. V42b.
1953 Tricolporopollenites megaexactus (Potonié) n.
comb., Thomson & Pfl ug, p. 100, pl. 12, fi gs
50–57, 74, 75.
1960 Cyrillaceaepollenites megaexactus (Potonié) n.
comb., Potonié, p. 102.
R e m a r k s. This species is known from the
Oligocene and Miocene deposits. In the studied
material these pollen grains were encountered
sporadically in samples with Tricolporopollenites
exactus, in quantities not exceeding 1%.
The two above-mentioned taxa (Tricolporopollenites
exactus and T. megaexactus) represent
subtropical (P2) element (Ziembińska-
Tworzydło et al. 1994b), and are similar to
pollen of the recent Cyrillaceae (genus Cyrilla
Gard.) and Clethraceae (genus Clethra L.).
The present-day genus Clethra (about 30
species of evergreen and deciduous trees and
shrubs) is distributed in subtropical zone of
South and North America, south-eastern Asia,
as well as in the mountains in tropical zone.
Clethra alnifolia L. is a shrub growing on
peat-bogs and in humid forests in the Atlantic
zone of North America. The monotypic genus
Cyrilla (C. racemifl ora L.) occurs on peat-bogs
in North America (Kearney 1901, Krüssmann
1976).
Familiae CYRILLACEAE,
CLETHRACEAE, ?ROSACEAE
(113) Tricolporopollenites bruhlensis
(Thomson 1950) Grabowska in Ziembińska-
Tworzydło et al. 1994
Pl. 13, fi g. 15
1950 Pollenites cingulum brühlensis n. spm. (Thomson);
Potonié, Thomson & Thiergart, p. 56, 63,
pl. B, fi gs 31–33.
1994b Tricolporopollenites brühlensis (Thomson)
Grabowska stat. nov.; Ziembińska-Tworzydło
et al., p. 27, pl. 16, fi gs 1–5.
R e m a r k s. Pollen grains of this species represent
subtropical element (P2), and occur in
the Eocene to Pliocene deposits (Ziembińska-
Tworzydło et al. 1994a, b). Several pollen
grains of this taxon were found in the studied
material.
Familia SAPOTACEAE
Tetracolporopollenites Thomson
& Pfl ug 1953
(114) Tetracolporopollenites andreanus
Bruch 1998
Pl. 14, fi g. 2a, b
1998 Tetracolporopollenites andreanus n. sp., Bruch,
p. 99, pl. 14, fi gs 20–22.
Pollen grains tetracolporate, in equatorial
view rectangular in outline, 25–30 × 20–22 μm
in size. Colpi diagonally crossed. Exine about
2 μm thick, surface very fi nely granulate.
R e m a r k s. This species was described from
the Upper Oligocene (?) deposits of Slovenia
(Bruch 1998). Its characteristic features are
diagonally crossed colpi. In the studied material
these pollen grains were encountered sporadically.