Acer chaneyi
Acer chaneyi is an extinct maple species in the family Sapindaceae described from a number of fossil leaves and samaras. The species is known from Oligocene to Miocene sediments exposed in Alaska, Idaho, Nevada, Oregon and Washington in the U.S. It is one of several extinct species belonging to the living section Rubra.
Taxonomy
Acer chaneyi is known from leaf and samara specimens which were recovered from a number of different formations in Western North America. The oldest occurrence is from the possibly Early Oligocene Gumboot Mountain flora of Southern Washington state followed by the Late Oligocene Kukak Bay flora in Alaska. In the early Miocene A. chaneyi is known from the Alaskan Kanalku Bay flora, Oregon Collawash and Little Butte flora. The Middle Miocene locations include the Skolai Creek flora of Alaska, Grand Coulee and Latah floras of Washington, John Day [Fossil Beds National Monument|Mascall flora] and Succor Creek floras in Oregon and the Latah and Clarkia flora in Idaho. Further Middle Miocene occurrences in Nevada are the Thurston Ranch flora, Deadman Creek flora, Pyramid flora, Purple Mountain flora, Eastgate flora, and Middlegate floras. Late Miocene occurrences in Oregon are the Weyerhauser flora, Hidden Lake flora, Austin flora, Tipton flora, Stinking Water flora, and Trout Creek floras. Late Miocene occurrences in Idaho are the Cartwright Ranch flora, Horseshoe Bend flora, Alkali Creek flora and Trapper Creek flora. Based on the identified fossil occurrences A. chaneyi has a temporal range of approximately 20 million years, the longest identified for any fossil species in Western North America. The species Acer ferrignoi is a possible descendant species that survived in the Oregon Cascades until 7 million years ago.The nomenclatural history for A. chaneyi is fairly complex: a number of different names have been applied to the fossils of different locations. The species was reviewed by paleobotanists Jack A. Wolfe of the United States Geological Survey, Denver office and Toshimasa Tanai of Hokkaido University., in a 1987 paper in the Journal of the Faculty of Science, Hokkaido University. The oldest name suggested for the fossils was Acer bendirei which was coined by Leo Lesquereux in 1883. The fossils used for his description of the species however were a mix of several different plants, and the type specimens were later transferred to the genus Platanus as P. bendirei. The next oldest name, Acer gigas, is from 1902 and was coined by Frank Knowlton for a fossil samara from the John Day formation. The fossil is missing the base of the fruit and the attachment scar, which is diagnostic for Acer: thus it was rejected by Wolfe and Tanai. Similarly they rejected A. grahamensis, for which the type specimen is also missing the attachment scar. They settled on A. chaneyi as the oldest valid species description coined by Knowlton in 1926 for leaves from the Latah Formation around Spokane, Washington.