Stomata in fossil Ceratozamia


Plate 2
1–8. Ceratozamia hofmannii Ettingsh., Osek, drill core Os 16, depth 79.2 m, North Bohemia, Czech Republic,uppermost lower Miocene (NM G 9465)
1. Outer surface of abaxial cuticle with openings of stomatal crypts, SEM micrograph, scale bar = 20 μm
2. Inner view of stoma, showing inner lamellae, subsidiary cells and adjacent cell pattern, scale bar = 20 μm
3. Inner view of stoma, showing inner lamellae, scale bar = 10 μm
4. Outer surface of adaxial cuticle, scale bar = 100 μm
5. Inner surface of abaxial cuticle with stomata and cell patterns over intercostal areas, scale bar = 100 μm
6. Adaxial cuticle in transmitted light, showing characteristic pattern of short and long cell structure,scale bar = 100 μm
7. Abaxial cuticle in transmitted light with stomata and rows of short cells, scale bar = 100 μm
8. Overall view of abaxial cuticle with distinctly demarcated costal and intercostal areas, scale bar = 300 μm
9. Ceratozamia hofmannii Ettingsh., adaxial cuticle, duplicate preparation from holotype (NHML),scale bar = 100 μm
10. Ceratozamia floersheimensis (Engelhardt) Kvaček, abaxial cuticle from specimen shown in Pl. 1, fig. 7,scale bar = 100 μm

New fossil records of Ceratozamia (Zamiaceae, Cycadales) from the European Oligocene and lower Miocene 

by Kvacek Z. (2014)

ZLATKO KVAČEK

Charles University in Prague, Faculty of Science, Institute of Geology and Palaeontology, Albertov 6, CZ 12843 Praha 2, Czech Republic

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by Acta Palaeobotanica 54(2): 231–247 – DOI: 10.2478/acpa-2014-0012 –

New_fossil_records_of_Ceratozamia_Zamiaceae_Cycada (1).pdf


Plate 3
1, 2. Ceratozamia microstrobila Vovides & J.D. Rees, cult. MBC
1. Adaxial epidermis with long thick-walled cells and narrower rows of short cells
2. Abaxial epidermis with amphicyclic stomata and rows of long and short narrower cells
3, 4. Ceratozamia mexicana Brongn., cult. K
3. Adaxial epidermis with long thick-walled cells and narrower rows of short cells
4. Abaxial epidermis with incompletely amphicyclic stomata and rows of long and short narrower cells
5, 6. Ceratozamia sabatoi Vovides et al., Querétaro, coll. Schutzmann BD 8665.2
5. Adaxial epidermis with long thick-walled cells and narrower rows of short cells
6. Abaxial epidermis with monocyclic stomata and rows of long and short narrower cells
7, 8. Ceratozamia norstogii D. W. Stev., cult. MBC
7. Adaxial epidermis with long cells and rows of short cells
8. Abaxial epidermis with incompletely amphicyclic stomata and rows of long and short narrower cells
9, 10. Ceratozamia hofmannii Ettingsh., Osek, Os16-2
9. Adaxial epidermis with long cells and rows of short cells
10. Abaxial epidermis with incompletely amphicyclic stomata and rows of long and short narrower cells
11, 12. Zamia paucijuga Wieland, coll. Schutzman S-55, Mexico
11. Adaxial epidermis with uniform pattern of narrow elongate cells
12. Abaxial epidermis with incompletely amphicyclic stomata and rows of nondifferentiated cells
13, 14. Dioon edule Lindl., cult. PRC
13. Adaxial epidermis with rows of shorter quadrangular and longer thick-walled cells
14. Abaxial epidermis with incompletely amphicyclic, deeply sunken stomata in crypts and rows of nondifferentiated cells
15, 16. Microcycas calocoma (Miq.) DC., cult. MBC
15. Adaxial epidermis with long elongate thick-walled and narrower thin-walled cells
16. Abaxial epidermis with incompletely amphicyclic stomata and rows of thick-walled and thin-walled cells

ABSTRACT

New compression leaf material of Ceratozamia (Zamiaceae) has been recognised in the EuropeanCenozoic. A leaflet of Ceratozamia floersheimensis (Engelhardt) Kvaček was recovered among unidentified mate-rial from the Oligocene of Trbovlje, former Trifail, Slovenia, housed in old collections of the Austrian GeologicalSurvey, Vienna. It is similar in morphology and epidermal anatomy to other specimens previously studied fromthe lower Oligocene of Flörsheim, Germany and Budapest, Hungary. A fragmentary leaflet assigned to C. hof-mannii Ettingsh. was recovered in the uppermost part of the Most Formation (Most Basin in North Bohemia,Czech Republic) and dated by magnetostratigraphy and cyclostratigraphy to CHRON C5Cn.3n, that is, the latestearly Miocene. It yielded excellently preserved epidermal structures, permitting confirmation of the generic affin-ity and a more precise comparison with this lower Miocene species previously known from Austria (Münzenberg,Leoben Basin) and re-investigated earlier. Both the Oligocene and Miocene populations of Ceratozamia are basedon isolated disarticulated leaflets matching some living representatives in the size and slender form of the leaf-lets. Such ceratozamias thrive today in extratropical areas near the present limits of distribution of the genusalong the Sierra Madre Orientale in north-eastern Mexico, in particular C. microstrobila Vovides & J.D. Reesand others of the C. latifolia complex, as well as C. hildae G.P. Landry & M.C. Wilson (“bamboo cycad”). Theoccurrence of Ceratozamia suggests subtropical to warm-temperate, almost frostless climate and a high amountof precipitation. The accompanied fossil vegetation of both species corresponds well with the temperature regime.While the Oligocene species in Hungary probably thrived under sub-humid conditions, the remaining occur-rences of fossil Ceratozamia were connected with humid evergreen to mixed-mesophytic forests.

Published by

Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.

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