Acer rousei
Encyclopedia
Acer rousei is an extinct maple
species
in the family Sapindaceae
described from a series of isolated fossil
samara
s. The species is solely known from the Early Eocene sediments exposed in south central British Columbia
, Canada adjacent to northeast Washington State, USA. It is the type species for the extinct monotypic
section Rousea.
Allenby Formation exposed near Princeton, British Columbia
and an additional three fruits from the Ypresian McAbee locality near Cache Creek, British Columbia
. The two Allenby Formation specimens were found at the Burke Museum of Natural History and Culture
location UWBM B3389, known as the One Mile Creek locality. Both the Allenby Formation and the unnamed formation which outcrops at the McAbee site preserve upland temperate floras which were first interpreted as being Microthermal
, however further study has shown them to be more mesothermal
in nature. The plant community preserved in the Allenby formation is a mixed confer-broad leaf forest with large pollen elements of birch
and golden larch, but also having notable traces of fir
and spruce
. In contrast the Cache Creek site is mostly broad leaf pollen with alder
and elm
dominating, and may represent a successional forest involving multiple volcanic ash eruptions. The species was known only from the Cache Creek and Princeton fossil localities when first described. A. rousei is among a number of Acer species described from the Princeton and related sites by Wolfe and Tanai.
Both the Acer rousei holotype
samara, number UWBM 56256 A,B and the paratype
UWBM 54107 A,B are currently preserved in the paleobotanical
collections housed at the Burke Museum of Natural History and Culture
, part of the University of Washington
in Seattle. They are from the Allenby Formation. The paratype UBCB 2401 is in the University of British Columbia
collections while the paratypes TMP P83.39.586 A,B and TMP P83.39.585 A,B are in the collections of the Royal Tyrrell Museum of Palaeontology
in Alberta. The last three paratypes are all from the Cache Creek Site. The specimens were studied by paleobotanists Jack A. Wolfe
of the United States Geological Survey, Denver office
and Toshimasa Tanai of Hokkaido University
. Wolfe and Tanai published their 1987 type description for A. rousei in the Journal of the Faculty of Science, Hokkaido University. The etymology
of the chosen specific name
rousei is in recognition Glenn Rouse, who supplied Wolfe and Tanai with Eocene fossils of Acer from British Columbia. A. stewarti is the only species assigned to the extinct section Rousea and is designated the type species for the section.
Maple
Acer is a genus of trees or shrubs commonly known as maple.Maples are variously classified in a family of their own, the Aceraceae, or together with the Hippocastanaceae included in the family Sapindaceae. Modern classifications, including the Angiosperm Phylogeny Group system, favour inclusion in...
species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the family Sapindaceae
Sapindaceae
Sapindaceae, also known as the soapberry family, is a family of flowering plants in the order Sapindales. There are about 140-150 genera with 1400-2000 species, including maple, horse chestnut and lychee....
described from a series of isolated fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
samara
Samara (fruit)
A samara is a type of fruit in which a flattened wing of fibrous, papery tissue develops from the ovary wall. A samara is a simple dry fruit and indehiscent . It is a winged achene...
s. The species is solely known from the Early Eocene sediments exposed in south central British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, Canada adjacent to northeast Washington State, USA. It is the type species for the extinct monotypic
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
section Rousea.
Taxonomy
Acer rousei was described from two complete fruit specimens which were recovered from outcrops of the early Eocene, YpresianYpresian
In the geologic timescale the Ypresian is the oldest age or lowest stratigraphic stage of the Eocene. It spans the time between and , is preceded by the Thanetian age and is followed by the Eocene Lutetian age....
Allenby Formation exposed near Princeton, British Columbia
Princeton, British Columbia
Princeton is a small town in the Similkameen region of southern British Columbia, Canada. It lies just east of the Cascade Mountains, which continue south into Washington, Oregon and California. The Tulameen and Similkameen Rivers converge here...
and an additional three fruits from the Ypresian McAbee locality near Cache Creek, British Columbia
Cache Creek, British Columbia
Cache Creek is a junction community northeast of Vancouver in British Columbia, Canada. It is on the Trans-Canada Highway in the province of British Columbia at its junction with northbound Highway 97...
. The two Allenby Formation specimens were found at the Burke Museum of Natural History and Culture
Burke Museum of Natural History and Culture
The Burke Museum of Natural History and Culture has been a Washington state museum since 1899. It is located at the University of Washington campus at the intersection of N.E. 45th Street and 17th Avenue N.E. in Seattle, Washington, USA, in the University District. It is the only major natural...
location UWBM B3389, known as the One Mile Creek locality. Both the Allenby Formation and the unnamed formation which outcrops at the McAbee site preserve upland temperate floras which were first interpreted as being Microthermal
Microthermal
In climatology, the term microthermal is used to denote the continental climates of Eurasia and North America.The word microthermal is derived from two Greek words meaning "having little heat." This is misleading, however, since the term is intended to describe only the temperature conditions that...
, however further study has shown them to be more mesothermal
Mesothermal
In climatology, the term mesothermal is used to refer to certain forms of climate found typically in the Earth's Temperate Zones. It has a moderate amount of heat, with winters not cold enough to sustain snow cover...
in nature. The plant community preserved in the Allenby formation is a mixed confer-broad leaf forest with large pollen elements of birch
Birch
Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...
and golden larch, but also having notable traces of fir
Fir
Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...
and spruce
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...
. In contrast the Cache Creek site is mostly broad leaf pollen with alder
Alder
Alder is the common name of a genus of flowering plants belonging to the birch family . The genus comprises about 30 species of monoecious trees and shrubs, few reaching large size, distributed throughout the North Temperate Zone and in the Americas along the Andes southwards to...
and elm
Elm
Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the plant family Ulmaceae. The dozens of species are found in temperate and tropical-montane regions of North America and Eurasia, ranging southward into Indonesia. Elms are components of many kinds of natural forests...
dominating, and may represent a successional forest involving multiple volcanic ash eruptions. The species was known only from the Cache Creek and Princeton fossil localities when first described. A. rousei is among a number of Acer species described from the Princeton and related sites by Wolfe and Tanai.
Both the Acer rousei holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
samara, number UWBM 56256 A,B and the paratype
Paratype
Paratype is a technical term used in the scientific naming of species and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany...
UWBM 54107 A,B are currently preserved in the paleobotanical
Paleobotany
Paleobotany, also spelled as palaeobotany , is the branch of paleontology or paleobiology dealing with the recovery and identification of plant remains from geological contexts, and their use for the biological reconstruction of past environments , and both the evolutionary history of plants, with a...
collections housed at the Burke Museum of Natural History and Culture
Burke Museum of Natural History and Culture
The Burke Museum of Natural History and Culture has been a Washington state museum since 1899. It is located at the University of Washington campus at the intersection of N.E. 45th Street and 17th Avenue N.E. in Seattle, Washington, USA, in the University District. It is the only major natural...
, part of the University of Washington
University of Washington
University of Washington is a public research university, founded in 1861 in Seattle, Washington, United States. The UW is the largest university in the Northwest and the oldest public university on the West Coast. The university has three campuses, with its largest campus in the University...
in Seattle. They are from the Allenby Formation. The paratype UBCB 2401 is in the University of British Columbia
University of British Columbia
The University of British Columbia is a public research university. UBC’s two main campuses are situated in Vancouver and in Kelowna in the Okanagan Valley...
collections while the paratypes TMP P83.39.586 A,B and TMP P83.39.585 A,B are in the collections of the Royal Tyrrell Museum of Palaeontology
Royal Tyrrell Museum of Palaeontology
The Royal Tyrrell Museum is a popular Canadian tourist attraction and a leading centre of palaeontological research noted for its collection of more than 130,000 fossils....
in Alberta. The last three paratypes are all from the Cache Creek Site. The specimens were studied by paleobotanists Jack A. Wolfe
Jack A. Wolfe
Jack Albert Wolfe was an American paleontologist best known for his studies of Tertiary climate in western North America through analysis of fossil angiosperm leaves.-External links:...
of the United States Geological Survey, Denver office
United States Geological Survey
The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology,...
and Toshimasa Tanai of Hokkaido University
Hokkaido University
Hokkaido University is one of the most prestigious universities in Japan. It can be seen in the several rankings such as shown below.-General Rankings:...
. Wolfe and Tanai published their 1987 type description for A. rousei in the Journal of the Faculty of Science, Hokkaido University. The etymology
Etymology
Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...
of the chosen specific name
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
rousei is in recognition Glenn Rouse, who supplied Wolfe and Tanai with Eocene fossils of Acer from British Columbia. A. stewarti is the only species assigned to the extinct section Rousea and is designated the type species for the section.