''Acer traini'' is an extinct

maple ''Acer'' () is a genus of trees and shrubs commonly known as maples. The genus is placed in the family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated since http ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

in the family

Sapindaceae The Sapindaceae are a family of flowering plants in the order Sapindales known as the soapberry family. It contains 138 genera and 1858 accepted species. Examples include horse chestnut, maples, ackee and lychee. The Sapindaceae occur in tempera ...

described from isolated

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

samaras. The species was described from

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

-aged fossils found in

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

and the

United States of America The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...

. It is one of several extinct species placed in the living section '' Glabra''.

History and classification

''Acer traini'' is represented by a group of fossil specimens from a number of different geologic deposits in western North America. The northernmost fossils have been reported from the Early Miocene Chilcotin River flora of Central

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

. Two localities in

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

have produced fossils of the species. The White Hills site of the Mascall Formation in Northeast Central Oregon and the Trout Creek flora of southeastern Oregon while the Trapper Creek flora found in southern central

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...

is the furthest east locality for the species. Two Early to early Middle Miocene floras in Nevada host ''A. traini'' fossils, the Thurston Ranch flora of northeastern Nevada and the southernmost occurrence of the species in the Purple Mountain flora in western central Nevada. The Chilcotin River flora found in preserved infilled paleovalleys overlain by

Chilcotin Group The Chilcotin Group, also called the Chilcotin Plateau Basalts, is a large area of basaltic lava that forms a volcanic plateau running parallel with the Garibaldi Volcanic Belt in south-central British Columbia, Canada. Predominantly, during Mioc ...

flood basalts while the Mascall formation is composed of temporary lake beds interbedded with lava flows of the Columbia River Basalt Group. Only one fossil is known from each locality, with the exception of the Trout Creek flora which produced two fossils, giving a total of only seven specimens. The holotype specimen of the species is number UMMP 65138, housed in the University of Michigan Museum of Paleontology and the paratype is specimen UCMP 9343, in the University of California Museum of Paleontology. The specimens were studied by paleobotanists

Jack A. Wolfe Jack Albert Wolfe (1936–2005) was a United States Geological Survey paleobotanist and paleoclimatologist best known for his studies of Tertiary climate in western North America through analysis of fossil A fossil (from Classical Latin ...

of the United States Geological Survey, Denver office and Toshimasa Tanai of Hokkaido University. Wolfe and Tanai published their 1987

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

for ''A. traini'' in the ''Journal of the Faculty of Science, Hokkaido University''. The

etymology Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological chan ...

of the chosen

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''traini'' is in recognition of Percy Train, a fossil collector who amassed large collections of fossils from the Trout Creek flora.

Description

The samaras of ''A. traini'' have an overall nutlet shape which is triangular with an average length between and ranging between wide and are "moderately inflated" with three distinct ridges. One of the ridges is very distinct, located in the middle of the nutlet and crossing it from the attachment scar to the nutlet tip, the other two are less pronounced. The wing has a length ranging from and a width of . The paired samaras have a 30°–40° attachment angle with the wing hosting six distinct veins that start at the nutlet tip and curve from the wing margin, forking three to four times each. Wolfe and Tanai note in the species description that the fossils are the first

Tertiary Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...

record of an ''

Acer glabrum ''Acer glabrum'' is a species of maple native to western North America, from southeastern Alaska, British Columbia and western Alberta, east to western Nebraska, and south through Washington, Oregon, Idaho, Montana and Colorado to California, Ar ...

'' (Douglas maple)-type fruit in western North America, and further note that no characters separate ''A. traini'' fruits from ''A. glabrum'' fruits. They suggest that, if fossil leaves are found associated with the fruits which match the living ''A. glabrum'' foliage, then ''A. traini'' could be considered a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are all ...

of ''A. glabrum''. However, until leaf fossils are found, they suggest the fossils be kept a separate species. Acer glabrum 5203

References

{{Taxonbar, from=Q4673178 traini Prehistoric angiosperms Plants described in 1987 Fossil taxa described in 1987 Miocene plants Flora of British Columbia Flora of Idaho Flora of Oregon Flora of Nevada Extinct flora of North America Fossils of Canada Fossils of the United States