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Araucaria rangiauriaensis
Araucaria rangiauriaensis Pole, Marc Philippe Alcheringa, 34(3): 235. Sep 2010
- Name
- Araucaria rangiauriaensis
- Rank
- Species
- Generic Name
- [Genus] Araucaria
- Authors (Pub.)
- Pole M. S.
Philippe M.
- Publication
- Cretaceous plant fossils of Pitt Island, the Chatham group, New Zealand [2010/9]
- Journal
- Alcheringa
- Volume
- 34
- Issue
- 3
- Page number
- 235
- Year
- 2010
- Fossil Status
- leafy twigs
- Stratigraphy
- Albian
- Strat. comment
- Tupuangi Formation
- Location
- Pitt Island, New Zealand
- Paleoregion
- Australia (New Zealand)
Data for Holotypus
- Repository
- Queensland Herbarium, Brisbane, Australia
- Repository Number
- SL5575, Tupuangi-09
- Diagnosis
- Unbranched shoots bearing
spirally arranged, loosely imbricate, clawlike,
bilaterally flattened, leaves, about
1.5–2.0 mm long and 0.5 mm wide, gradually
narrowing to an acute apex. The stomatal
complexes are restricted to two zones on the
adaxial edge of the leaf; each zone has 2–3
rows of stomatal complexes that are typically
tightly chained, and commonly touching
complexes in adjacent rows; complexes are
dicyclic, with 4–6 subsidiary cells, and randomly
oriented. The subsidiary cells have
clearly thickened periclinal walls relative to
normal epidermal cells and form a shallow
dish-like structure. The guard cell pair is ca
45 mm long, with an elliptical outline with
flattened sides and ends. The polar ends of the
guard cells sit in shallow cups (they are not
reflexed outwards) that are barely, if at all,
divided in the middle. The surface level of the
stomatal complex is depressed below the surface
of the leaf, which is otherwise featureless. The stomatal pore is elliptical but typically
occluded with cuticular material. Normal epidermal
cells have straight or wavy walls, and
length:width ratios up to 8:1 (normally less).
