York Ranch Flora (Oligocene of the United States)

Where: Madison County, Montana (45.5° N, 112.5° W: paleocoordinates 46.7° N, 106.1° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Dunbar Creek Member (Renova Formation), Oligocene (33.9 - 23.0 Ma)

• bed-level stratigraphic resolution

Environment/lithology: fluvial; poorly lithified, brown, silty shale and sandstone

• The coarse, lens-enclosing sandstone is about 150 ft. thick and overlain by weakly consolidated gravels. It contains numberous small, non-fossiliferous clay or silt pockets, is distinctly cross-bedded at low angles and the only outcrop of this kind in the Fossil Basin. Generally weakly consolidated, the sandstone is packed, however, forming several resistant low ledges, iron-cemented and rust-stained. Mild rain and melting snow is usually redily absorbed by the remaining sandstone. Both, the angular grains of the sandstone and the mica flakes of the lens, suggest a short distance of transportation for the sediments

Size classes: macrofossils, microfossils

Preservation: mold/impression, adpression

Collection methods: quarrying,

Primary reference: H. F. Becker. 1973. The York Ranch Flora of the Upper Ruby River Basin, Southwestern Montana. Palaeontographica Abteilung B 143:18-93 [H. Sims/H. Lindon/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 23793: authorized by Hallie Sims, entered by Heather Lindon on 21.07.2002, edited by Jason Cassara

Creative Commons license: CC BY (attribution)

Taxonomic list

• Includes a crinoid stem fragment and echinoderm spine fragments, probably reworked from Mississippian Madison Limestone.
unclassified
  -
Coniferites
  -
Polypodiopsida
 Equisetales - Equisetidae
Equisetum aquatile n. sp. horsetail
 Coniferales - Cupressaceae
Sequoia affinis Lesquereux 1876 coast redwood
Lesquereux
cf. Metasequoia sp. Miki 1941 dawn redwood
Winged seeds, cf. Metasequoia ?
Dicotyledoneae
 Ericales - Ericaceae
cf. Arctostaphylos sp. Adanson 1763 heather
Leaf, cf. Arctostaphylos ?
Angiospermae
 Laurales - Lauraceae
Sassafras ashleyi sassafras
Axelrod
Sassafras hesperia sassafras
Berry
 Proteales - Platanaceae
cf. Platanus sp. Linnaeus 1753 plane tree
 Saxifragales - Cercidiphyllaceae
Cercidiphyllum arcticum katsura
(Heer) Brown
 Saxifragales - Hamamelidaceae
Exbucklandia oregonensis pipli
(Chaney) Brown
 Cornales - Cornaceae
Cornus ovalis Lesquereux 1878 dogwood
Lesquereux
 Cornales - Nyssaceae
Nyssa crenata tupelo
Chaney
 Lamiales - Bignoniaceae
Catalpa rubyensis n. sp. trumpet vine
 Lamiales - Scrophulariaceae
Paulownia columbiana figwort
Smiley
 Mesangiosperms - Araceae
Araceaeites sp. Fritel 1910
 Poales - Typhaceae
Typha lesquereuxi Cockerell 1908 bulrush
Cockerell
 Poales - Poaceae
"? Gramineae indet." = Poaceae
"? Gramineae indet." = Poaceae Barnhart 1895 true grass
 Vitales - Vitaceae
Vitis muscadinioides grapevine
Becker
Vitis washingtonensis grapevine
(Knowlton) Brown
cf. Vitis sp. Linnaeus 1753 grapevine
Seed, cf. Vitis ?
 Fagales - Fagaceae
Castanea spokanensis chestnut
(Knowlton) Chaney & Axelrod
Quercus ? dispersa Lesquereux 1878 oak
(Lesquereux) Axelrod
 Fagales - Betulaceae
Betula fairii Knowlton 1926 birch
Knowlton
Carpinus lanceolata hornbeam
Becker
Carpinus fraterna Lesquereux 1883 hornbeam
Lesquereux
Alnus jarbidgana alder
Axelrod
Alnus relata alder
(Knowlton) Brown
 Fagales - Juglandaceae
Juglans cf. regia Linnaeus 1753 walnut
L.
Carya libbeyi hickory
(Lesquereux) MacGinitie
"Carya antiquorum" = Hicoria antiquora Newberry 1868
Newberry
 Rosales - Rhamnaceae
Rhamnus crocea buckthorn
Nuttall
 Rosales - Ulmaceae
Zelkova hesperia zelkova
Brown
Zelkova nervosa zelkova
(Newberry) Brown
Celtis chaneyi hackberry
Smiley
Celtis mccoshii Lesquereux 1883 hackberry
Lesquereux
Ulmus montanensis elm
Becker
Ulmus speciosa Newberry 1883 elm
Newberry
 Rosales - Rosaceae
cf. Potentilla sp. Linnaeus 1753 cinquefoil
Unidentified leaf, cf. Potentilla ?
Rosa hilliae Lesquereux 1883 rose
Lesquereux
Prunus lyoniifolia n. sp. plum
Prunus morangensis plum
Axelrod
Prunus scottii plum
Heer
Prunus (Amygdalus) wilcoxiana plum
(Berry) LaMotte
Spiraea clavidens meadowsweet
Becker
 Malpighiales - Salicaceae
Populus adamantea poplar
Becker
Populus cedrusensis poplar
Wolfe
Populus payettensis poplar
(Knowlton) Axelrod
Populus washoensis poplar
Brown
Populus sp. Linnaeus 1753 poplar
Populus eotremuloides Knowlton 1898 poplar
Knowlton
Populus balsamoides Göppert 1855 poplar
Goeppert
Salix cockerelli willow
Brown
Salix hesperia willow
(Knowlton) Condit
Salix laevigatoides willow
Axelrod
Salix longiacuminata willow
Knowlton
Salix stipulata n. sp. willow
Salix succorensis willow
Chaney & Axelrod
Salix cf. truckeana Chaney 1944 willow
Chaney
Salix schimperi Lesquereux 1888 willow
Lesquereux
Salix wimmeriana Göppert 1861 willow
Goeppert
 Fabales - Fabaceae
Leguminosites sp. Bowerbank 1840 legume
Cercis spokanensis Knowlton 1926 redbud
Knowlton
 Celastrales - Celastraceae
cf. Euonymus spp. Linnaeus 1753 spindle tree
Leaf, cf. Euonymus ?
 Malvales - Tiliaceae
Tilia inaequalis linden
MacGinitie
 Sapindales - Anacardiaceae
Rhus praeovata sumac
Chaney
Rhus milleri Hollick 1904 sumac
Hollick
 Sapindales - Sapindaceae
Acer glabroides Brown 1937 maple
Brown
Lycopodiopsida
 Isoetales - Isoetaceae
Isoetes trullata n. sp. quillwort
Antholithes
  -
Carpites
  -
Carpites "sp. A" Schimper 1874
Carpites "sp. B" Schimper 1874
Carpites "sp. C" Schimper 1874
Carpites "sp. D" Schimper 1874
Carpites "sp. E" Schimper 1874
Carpites "sp. F" Schimper 1874
Carpites "sp. G" Schimper 1874
Carpites "sp. H" Schimper 1874
Carpites "sp. I" Schimper 1874
Carpites "sp. J" Schimper 1874
Carpites "sp. K" Schimper 1874
Carpites "sp. L" Schimper 1874
Carpites "sp. M" Schimper 1874
Carpites "sp. N" Schimper 1874
Carpites "sp. O" Schimper 1874
Carpites "sp. P" Schimper 1874
Carpites "sp. Q" Schimper 1874
Carpites "sp. R" Schimper 1874
Carpites "sp. S" Schimper 1874
Carpites "sp. T" Schimper 1874
Carpites "sp. U" Schimper 1874
Carpites "sp. V" Schimper 1874
Carpites "sp. W" Schimper 1874
Carpites "sp. X" Schimper 1874
Carpites "sp. Y" Schimper 1874
Carpites "sp. Z" Schimper 1874
Carpites "sp. 1" Schimper 1874
Carpites "sp. 2" Schimper 1874
Carpites "sp. 3" Schimper 1874
Carpites "sp. 4" Schimper 1874
Carpites "sp. 5" Schimper 1874
Carpites "sp. 6" Schimper 1874
Carpites pruniformis
  -
Carpites pruniformis n. sp. Heer 1859
Insecta
  -
Insecta indet. Linnaeus 1758 insect
wings of Diptera and other orders
 Dicondylia -
Coleoptera indet. Linnaeus 1758 beetle
 Ephemeroptera - Isonychiidae
Isonychia sp. Eaton 1871 mayfly
mayfly
unclassified
  -
Annelida indet. Lamarck 1809
Aves
  -
Aves indet. Linnaeus 1758 bird
Feather
Actinopteri
 Cypriniformes - Cyprinidae
Amyzon sp. Cope 1872 carp-like fish
Catastomid fish
Pisces
  -
"Pisces indet." = Osteichthyes
"Pisces indet." = Osteichthyes Huxley 1880 bony fish
Fish scales