Eucommia montana R.W. BR.

Smith, MacKenzie A., Greenwalt, Dale E. & Manchester, Steven R., 2023, Diverse Fruits And Seeds Of The Mid-Eocene Kishenehn Formation, Northwestern Montana, Usa, And Their Implications For Biogeography, Fossil Imprint 79 (1), pp. 37-88 : 63

Eucommia montana R.W. BR.

Text-fig. 11e–g

M a t e r i a l. USNM PAL 717259, 622651, 623020, 623513, 624027, 624249, 624336, 624374, 624717, 624808, 717508, 625160, 625523, 625756, 768185.

L o c a l i t i e s. Dakin, Disbrow Creek, Park and Spring.

D e s c r i p t i o n. Samaras 1.6–8.9 mm long to 0.7– 4.5 mm wide; endocarp 1.0– 6.5 mm long to 0.6–3.2 mm wide; fruits and seed bodies elliptical with seed bodies in the center of the samara; reticulate venation over the endocarp and a strong intramarginal or marginal vein along the wing margins; stigmatic cleft, positioned laterally near the apex; basal stipe present.

R e m a r k s. Size and length width ratios are the key distinguishing factors for fossil Eucommia species endemic to east Asia ( Call and Dilcher 1997, Manchester et al. 2009). These fossils fall within the size ranges of Eucommia montana which displays a wide range ( Becker 1969, Call and Dilcher 1997). Eucommia montana is known from the early Eocene to Oligocene as far north as Quilchena, British Columbia and as far south and east as Florissant, Colorado ( Call and Dilcher 1997). This species had smaller fruits than those known from the Eocene of Mississippi ( Call and Dilcher 1997) and Oligocene of southern Mexico ( Magallón-Puebla and Cevallos-Ferriz 1994). Eucommia is now endemic to China, but its fossil record includes North American and European as well as Asian occurrences ( Manchester et al. 2009).

Family Oleaceae HOFFMANNS. et LINK

Genus Fraxinus L.

Figures

Text-fig. 11. a: USNM PAL 624090 Chenopodium sp. 1. Scale bar 1mm. b: USNM PAL 624372 Chenopodium sp. 2. Scale bar 2mm. c: Chenopodium pratericola from Minnesota Wildflowers 2023b. d: Chenopodium hybridum, FLAS seed collection. Scale bar 1mm. e: USNM PAL 625523 Eucommia montana showing subapical stigmatic cleft, seed body and stipe. Scale bar 1mm. f: USNM PAL 625160 E. montana showing faint subapical stigmatic cleft and stipe. Scale bar 2mm. g: USNM PAL 768185 E. montana showing subapical stigmatic cleft, reticulate venation and stipe. Scale bar 2mm. h: USNM PAL 624697 Fraxinus sp. samara showing long persistent pedicel, seed body and wing. Scale bar 5mm. i: USNM PAL 625396 Catalpae seed with frayed wings. Scale bar 2mm. j: USNM PAL 624316 Catalpae seed with frayed wings. Scale bar 1mm. k: USNM PAL 722179 Apialean schizocarp with lateral spines and line of dehiscence. Scale bar 2mm.