Revision Of The Early Oligocene Flora Of Hrazený Hill (Formerly Pirskenberg) In Knížecí Near Šluknov, North Bohemia
Author
Kvaček, Zlatko
Charles University in Prague, Faculty of Science, Albertov 6, CZ - 128 43 Praha 2, the Czech Republic; e-mail: kvacek @ natur. cuni. cz;
Author
Teodoridis, Vasilis
Charles University in Prague, Faculty of Education, Magdalény Rettigové 4, CZ - 116 39 Praha 1, the Czech Republic; e-mail: vasilis. teodoridis @ pedf. cuni. cz;
Author
Zajícová, Jana
Charles University in Prague, Faculty of Science, Albertov 6, CZ - 128 43 Praha 2, the Czech Republic; e-mail: jana. zajicova @ natur. cuni. cz.
text
Acta Musei Nationalis Pragae Series B
2015
2015-10-31
71
1 - 2
55
102
http://dx.doi.org/10.14446/amnp.2015.55
journal article
10.14446/AMNP.2015.55
2533-4069
13182943
Liriodendron haueri
ETTINGSHAUSEN
Pl. 3, Fig. 1–4, Pl. 6, Fig. 1
1869
Liriodendron haueri
ETTINGSHAUSEN
, p. 9, pl. 41, fig. 10–10b.
1961
Liriodendron procaccinii
UNGER
; Knobloch, p. 273, pl. 7, fig. 1, 3.
1961
Styrax
sp.
; Knobloch, p. 288, pl. 14, fig. 4.
Leaves broadly ovate with four lobes arising from a point one third of the blade width or only shallowly bilobate, leaf blade
41–82 mm
long and 21 – ca.
90 mm
wide, base widely cuneate, petiolate, petiole maximum
50 mm
long. Midrib strong and straight, secondary veins arising at an angle of 40–50°, opposite or alternate, every second joined by a broken tertiary vein to the next vein above and then looping. Lowermost pairs sending fine outer loops towards the margin. Tertiary venation forms polygonal fields. Mesophyll tissue with small lens-shaped secretory cells, cuticles smooth, the abaxial surface with scattered stomata openings, otherwise cell structure poorly preserved.
D i s c u s s i o n. One aberrant leaf impression with only two shallow lobes was referred to
Styrax
by
Knobloch (1961)
but a similar leaf impression from Markvartice was assigned to
Liriodendron
on account of its epidermal anatomy (
Bůžek et al. 1976
, pl. 3, fig. 8). Of the available names for fossil species of
Liriodendron
(see e.g.
Archenegg 1894
) we prefer here
Liriodendron haueri
ETTINGSHAUSEN
rather than
L. procaccinii
UNGER
(selected by
Knobloch 1958
,
1961
) because the former name is based on a leaf impression from the Oligocene of North
Bohemia
(see
Hably et al. 2001
, p. 27, pl. 20, fig. 2,
Akhmetiev et al. 2009
, pl. 13, fig. 3) and was accepted by the previous authors dealing with other Palaeogene occurrences of Tulip tree foliage in this region (see e.g.
Bůžek et al. 1976
,
Walther 1998
).
L. procaccinii
is a common designation for fossil foliage of
Liriodendron
distributed mainly in Europe during the late Neogene (see
Saporta and Marion 1876
– Meximieux,
Knobloch 1998
– Willershausen).
L. haueri
differs from
L. procaccinii
in acute lobes contrary to mostly rounded lobes in the Italian Neogene populations (
Knobloch 1998
, p. 14). Revision of the latter species
type
material from Senigallia,
Italy
(
Massalongo and Scarabelli 1859
, Kustatcher et al. 2014) is required. Two extant species differ in the surface sculpture of the abaxial cuticle. The leaves in
L. tulipifera
L. from E and SE North America are abaxially smooth, in
L. chinense
(
HEMSLEY
)
SARGENT
from eastern
China
and
Vietnam
are papillate. In this respect our material looks to be similar to
L. tulipifera
.
It is noteworthy that in living species of Tulip tree the fruitlets survive in large quantities after the season under the trees while foliage readily decomposes over the winter. This is perhaps a reason why leaf impressions are less common than fruitlets in the fossil state (e.g., at Markvartice –
Bůžek et al. 1976
, Roudníky –
Kvaček et al. 2014
). This is however not the case at the Knížecí site, where no fruitlets have yet been recovered.
M a t e r i a l. Leaf impressions, NM-G2856a–f with cuticle, NM-G2859, NM-G2997, NM-G8591.