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Wintucycas stevensonii
Wintucycas stevensonii L.C.A. Martínez, Artabe, Bodnar Bot. J. Linn. Soc., 170(3): 438. 19 Oct 2012
- Name
- Wintucycas stevensonii
- Rank
- Species
- Generic Name
- [Genus] Wintucycas
- Authors (Pub.)
- Martínez L. C. A.
Artabe A. E.
Bodnar J.
- Publication
- A new cycad stem from the Cretaceous in Argentina and its phylogenetic relationships with other Cycadales [2012/10]
- Journal
- Botanical Journal of the Linnean Society
- Volume
- 170
- Issue
- 3
- Page number
- 438
- Year
- 2012
- Fossil Status
- stems
- Stratigraphy
- Upper Cretaceous
- Strat. comment
- Allen Formation
- Location
- Salitral Ojo de Agua, Río Negro province, Patagonia, Argentina
- Paleoregion
- America (South)
Data for Holotypus
- Repository
- Universidad Nacional del Comahue (MUCPb), Paleontological Collection, Neuquén, Argentina
- Repository Number
- MUCPb-369
Data for Isotypus
- Repository
- Museo de La Plata, La Plata, Argentina
- Repository Number
- LPPB-13876, pmLPPB-1604 to pmLPPB-1608
Data for Paratypus
- Repository
- Universidad Nacional del Comahue (MUCPb), Paleontological Collection, Neuquén, Argentina
- Repository Number
- MUCPb-370, MUCPb-371 and MUCPb-372
- Diagnosis
- A columnar and polyxylic stem, covered by persistent
rhomboidal leaf bases. A wide and parenchymatous
central pith with mucilage canals, idioblasts
and medullary vascular bundles. The secondary
vascular cylinder comprises a medullary vascular
system and a cylindrical vascular system. The medullary
vascular system is composed of many medullary
vascular bundles. The cylindrical vascular
system has concentric rings of secondary xylem
and phloem toward the cortex, and centripetal
bundles adjacent to the innermost ring. Manoxylic
secondary xylem, with homocellular, multiseriate
rays one to four cells wide. Secondary phloem with
parenchyma cells and abundant mucilage canals.
Cortex composed of parenchyma cells and idioblasts,
mucilage canals and girdling leaf traces. Foliar
traces with an elaborated omega pattern. Leaf bases
with simple and unbranched trichomes on the
adaxial side.