A Review Of The Early Miocene Mastixioid Flora Of The Kristina Mine At Hrádek Nad Nisou In North Bohemia (The Czech Republic)
Author
Dedicated in memory of the late FrantiŠek Holý (1935 - 1984), an eminent Czech palaeobotanist
Author
Holý, František
National Museum, Václavské nám. 68,115 79 Prague 1, the Czech Republic
Author
Kvaček, Zlatko
Institute of Geology and Palaeontology, Faculty of Science, Charles University in Prague, Albertov 6, 128 43 Prague 2, the Czech Republic, e-mail: kvacek @ natur. cuni. cz
Author
Teodoridis, Vasilis
Department of Biology and Environmental Studies, Faculty of Education, Charles University in Prague, M. D. Rettigové 4, 116 39 Prague 1, the Czech Republic, e-mail: vasilis. teodoridis @ pedf. cuni. cz
text
Acta Musei Nationalis Pragae Series B
2012
2012-12-31
68
3 - 4
53
118
journal article
10.5281/zenodo.13191145
2533-4069
13191145
Tetraclinis salicornioides
(
UNGER
)
KVAČEK
Pl. 1, fig. 6, pl. 4, fig. 12, pl. 10, fig. 6
1847
Thuites salicornioides
UNGER
, p. 11, pl. 2, figs 1-4, pl. 20, fig. 8 (Radoboj).
1977a
Tetraclinis
sp.
; Holý, p. 111 (Hrádek/N., Kristina Mine).
1989
Tetraclinis salicornioides
(
UNGER
)
KVAČEK
, p. 48, pl. 1, fig. 11, pl. 2, figs 2-14, pl. 3, figs 1-4, text-fig. 1 (Hrádek/N., Kristina Mine and many other sites, full synonymy).
Isolated cladode-like branch segments, up to
10 mm
long,
2–5 mm
wide, corresponding to pseudo-whorls, composed of pairs of dimorphic facial and lateral leaves with rounded to bluntly mucronate apices and rounded base, in each pseudo-whorl fused along most of their length to form a dorsoventrally flattened phylloclade-like segment, simple pseudo-whorls oval, triveined in surface view, wider pseudo-whorls at nodes of branching, expanded apically, showing five prominent longitudinal lines on either surface. Facial leaves adpressed, ob-triangular, with obvious central midvein, lateral leaves lanceolate to falcate, each folded along its midvein in the plane of compression, shorter than the facial, closely imbricate, more commonly fused to the margins of the facial leaves. Segments showing thickly cutinized epidermis with heavily papillate outer surface, non-modified cells irregularly disposed and stomata in irregular short rows, monocyclic to incompletely amphicyclic. A single incomplete seed cone with only three cone scales preserved was recovered in the Kristina Mine (
Holý 1975
, pl. 2, fig. 1, recorded as
Tetraclinis
sp.
and Kvaček 1989, pl. II(6), fig. 4, assigned to
Tetraclinis salicornioides
). The probably unripen cone is
8-10 mm
large, with decussately arranged cone scales of subtriangular outline, abaxially bearing a short mucro slightly below the middle of the scale length on radially striated bract area.
D i s c u s s i o n: The record does not deviate from the other of this species from Europe (see, e.g.,
Knobloch and Kvaček 1976
,
Walther and Kvaček 2007
) and stresses the difference in seed cones between
T. salicornioides
with the subcentral mucro and
T. brachyodon
with the subapical mucro (Kvaček et al. 2000). Impressions of sterile foliage of
Tetraclinis salicornioides
are almost indistinguishable from an unrelated extinct cupressoid conifer
Ditaxocladus
S.X.
GUO
et Z.H.
SUN
occurring in the Late Cretaceous and the Palaeocene in the Northern Hemisphere (
Guo et al. 2012
). The sprays of both conifers differ in the general form, which is slender elongate in
Ditaxocladus
and widely spread in
Tetraclinis salicornioides
. More pronounced differences are in the seed cones (subglobose in racemose fertile branches in
Ditaxocladus
vs quadrivalvate solitary, rarely paired in
Tetraclinis
) and leaf anatomy (non-papillate straight-walled stomatal zones with thin Florin rings in
Ditaxocladus
vs thick and papillate cuticles with undulate anticlines and strong Florin rings around the stomatal pits in
Tetraclinis salicornioides
- see
Guo et al. 2012
). According to
Kvaček et al. (2011)
,
T. salicornioides
may be better compared ecologically to
Calocedrus macrolepis
KURZ
distributed in SE
China
,
Myanmar
(
Burma
),
Thailand
and
Vietnam
based on its foliage physiognomy.
M a t e r i a l: Fragmentary branches isolated on slides, G 8874a-b, 8875a-b, 8876-78 (KR 238, 272, 323, 344, 345), a seed cone, G 4590.
Glyptrostrobus
ENDLICHER