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Platycarya americana
Platycarya americana L.J. Hickey Mem. Geol. Soc. Amer., 150: 118. 19 Jul 1977
- Name
- Platycarya americana
- Rank
- Species
- Generic Name
- [Genus] Platycarya
- 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
- 118
- Year
- 1977
- Fossil Status
- infructescences
- Stratigraphy
- Thanetian
- Location
- White Butte, Stark County, North Dakota, USA
- Paleoregion
- America (North)
Data for Holotypus
- Repository
- National Museum of Natural History, Smithsonian Institution, Washington, USA
- Repository Number
- USNM 42992 (catkin)
Data for Paratypus
- Repository
- National Museum of Natural History, Smithsonian Institution, Washington, USA
- Repository Number
- catkins: PU 20060 [pl. 14: 5] (catkin), 20061, 20063 [pl. 14: 4] (catkin bract); USNM 43165 [pl. 14: 6] (catkin), 43166 [pl. 14: 7] (catkin), 43167A [pl. 14: 8] (catkin), B, 43171; fruits: USNM 167481A [pl. 15: 2] (fruit), B [pl. 15: 3] (fruit), 167482 [pl. 15: 4] (fruit), 167515, 167516 [pl. 15: 7] (fruit)
- Diagnosis
- Remains consisting of catkins, isolated bracts, and fruits. Catkins stout and
woody, often carbonized or heavily limonitized, and consisting of spirally arranged acuminate tipped bracts; shape ovoid to oblong; 1.5 to 4 cm long; 0.8 to 1.3 cm wide; born on a stout peduncle that is 2 to 3 mm broad and as much as 3 cm long; peduncle becomes abruptly wider just below base of catkin and often shows scars interpreted as places of leaf attachment.
Catkins occur as impressions, carbonized compressions, and limonite
overgrowths. Bracts of catkins ovate, with an acuminate beak as much as 2 mm in length, margin entire, average dimensions 7 mm long by 2.5 mm wide, often slightly curved; surface of bract marked by a longitudinal ridge or depression on its axis, paralleled by 3 less prominent lateral ridges. Isolated bracts of the same morphology are included in this species. Fruits found associated with, but not attached to, a catkin and are impressions and partial limonite petrifactions. Fruits consist of a dorsoventrally flattened central nutle.t with two wings; form obovate, I from 3.5 to 4 mm, w approximately
the same and frequently exceeding the length; receptacular end of fruit less flattened and containing a rounded socket that fits over the pedicle; distal end of fruit deeply embayed between the wings and terminating in an obtuse point; no trace of the stigmas remains; nutlet ovoid, surface marked by a longitudinal furrow and a pair of exmedially curved lateral furrows originating at the receptacle and running midway between the midline and the edge
of the nutlet. These furrows match those found on modern nutlets of Platycarya.
