Diverse Fruits And Seeds Of The Mid-Eocene Kishenehn Formation, Northwestern Montana, Usa, And Their Implications For Biogeography
Author
Smith, MacKenzie A.
Author
Greenwalt, Dale E.
Author
Manchester, Steven R.
text
Fossil Imprint
2023
2023-11-07
79
1
37
88
http://dx.doi.org/10.37520/fi.2023.004
journal article
10.37520/fi.2023.004
2533-4069
10481035
Genus
Dipteronia
OLIV
.
Text-fig. 9a
M a t e r i a l. USNM PAL 625742.
L o c a l i t y. Spring.
D e s c r i p t i o n.
Samara
15.0 mm tall,
10.5 mm
wide; pedicel
4.4 mm
long,
0.4 mm
wide; disc
0.5 mm
tall,
1.7 mm
wide; abortive fruit
1.1 mm
in diameter; laminated vascular bundle emerging out of disc and into flat, circular seed body 1.0 mm in diameter, surrounded by circular wing
5.2 mm
in diameter; veins radiate from center, dichotomizing occasionally between margin or halfway between margin and seed body; fimbrial vein surrounds wing.
R e m a r k s. The presence of a hypogynous perianth and disc scar at the junction of the pedicel and fruit and shape of the samara conform to
Dipteronia
. Fimbrial veins may be absent in
Dipteronia
fruit such as
Dipteronia sinensis
OLIV
.
or present such as in
Dipteronia dyeriana
HENRY
and
Dipteronia brownii
MCCLAIN
et
MANCHESTER
(
McClain and Manchester 2001
).
Dipteronia
fruits are known from the Paleocene of Wyoming, the middle and late Eocene of British Columbia, Washington, Oregon and Colorado and the early Oligocene of Oregon (
McClain and Manchester 2001
), as well as from the early Oligocene of western
China
(
Ding et al. 2018
).