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Dicotylophyllum mercerense
Dicotylophyllum mercerense L.J. Hickey Mem. Geol. Soc. Amer., 150: 149. 19 Jul 1977
- Name
- Dicotylophyllum mercerense
- Rank
- Species
- Original spelling
- mercerensis
- Generic Name
- [Genus] Dicotylophyllum
- Authors (Pub.)
- Hickey L. J.
- Publication
- Stratigraphy and paleobotany of the Golden Valley Formation (Early Tertiary) of Western North Dakota [1977/7]
- Journal
- Memoirs of the Geological Society of America
- Volume
- 150
- Page number
- 149
- Year
- 1977
- Fossil Status
- leaves
- Stratigraphy
- Thanetian
- Location
- Goodman Creek Bluffs, Mercer County, North Dakota, USA
- Paleoregion
- America (North)
Data for Holotypus
- Repository
- National Museum of Natural History, Smithsonian Institution, Washington, USA
- Repository Number
- USNM 43239
Data for Paratypus
- Repository
- National Museum of Natural History, Smithsonian Institution, Washington, USA
- Repository Number
- USNM 43240
- Diagnosis
- Leaves slightly asymmetrical; elliptic to wide elliptic; l/w ratio 1.3 to 1.7;
I 5.5 to 6.8 cm; w 4.1 to 6.8 cm; apex rounded to acute; base cordate; petiole 3 mm in width, length unknown; margin evenly small crenate and nonglandular; texture chartaceous. Venation perfect acrodromous with three strong primaries flanked by a pair of secondaries originating at the top of the petiole; primaries thick, with several strong excurrent outer branches toward the apex; secondaries diverging at high acute angles from the primaries,
thick, generally oriented perpendicular to the primaries with a ramification in the middle of the interprimary space; outer secondaries camptodromous, giving off a branch that runs to the tip of the crenation. Tertiaries originating at nearly right angles, intermediate in size between the secondary and ultimate venation; highest order of venation, sixth to seventh; rank of highest venation showing excurrent branching, fourth; areoles moderate to large,
0.8 to 1.8 mm in diameter, equant and pentagonal, and with no freely ending veinlets.
