Acer alaskense
Encyclopedia
Acer alaskense is an extinct maple
species
in the family Sapindaceae
described from a fossil
leaf
. The species is solely known from the Latest Paleocene sediments exposed in the Matanuska River Valley
, Matanuska-Susitna Borough, Alaska
. It is the type species for the extinct section Alaskana.
formations. Sediments of the formation are mainly claystone through sandstone, and conglomerates with interbedded deposits of bituminous coal. Based on the surrounding formations and the floral composition of fossils in the formation itself, the Chickaloon dates to the Paleocene
with Acer alaskense known only from the latest Paleocene section exposed in the Even Jones coal mine.
(number "USNM 396009"), which is currently preserved in the paleobotanical
collections housed at the National Museum of Natural History
, part of the Smithsonian Institution
in Washington, D.C.
.
The specimen was 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. alaskense in the Journal of the Faculty of Science, Hokkaido University. The etymology
of the chosen specific name
alaskense is in recognition of the type locality in the state of Alaska. A. alaskense is the oldest occurrence of the maple genus, Acer
, with the second-oldest being A. douglasense
from the Early Eocene sediments of the Paleocene-Eocene West Foreland Formation. In their type description Wolfe and Tanai designated A. alaskense as the type and only species for the extinct Acer section Alaskana.
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 fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
leaf
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
. The species is solely known from the Latest Paleocene sediments exposed in the Matanuska River Valley
Matanuska River
The Matanuska River is a river, approximately 75 miles long, in Southcentral Alaska, United States. It drains a broad valley south of the Alaska Range known as the Matanuska-Susitna Valley....
, Matanuska-Susitna Borough, Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
. It is the type species for the extinct section Alaskana.
Type locality
The species was described from a single full-leaf specimen found in the Chickaloon Formation, which underlies the Kenai GroupKenai Group
Kenai Group is a name given by Dall and Harris to sedimentary rocks in the Cook Inlet basin in Alaska. These rocks are instead called the Kenai Formation by several other authors....
formations. Sediments of the formation are mainly claystone through sandstone, and conglomerates with interbedded deposits of bituminous coal. Based on the surrounding formations and the floral composition of fossils in the formation itself, the Chickaloon dates to the Paleocene
Paleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
with Acer alaskense known only from the latest Paleocene section exposed in the Even Jones coal mine.
History and classification
Acer alaskense was described from a solitary specimen, the holotypeHolotype
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...
(number "USNM 396009"), which is 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 National Museum of Natural History
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. Admission is free and the museum is open 364 days a year....
, part of the Smithsonian Institution
Smithsonian Institution
The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...
in Washington, D.C.
Washington, D.C.
Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....
.
The specimen was 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. alaskense 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...
alaskense is in recognition of the type locality in the state of Alaska. A. alaskense is the oldest occurrence of the maple genus, Acer
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...
, with the second-oldest being A. douglasense
Acer douglasense
Acer douglasense is an extinct maple species in the family Sapindaceae described from fossil leaves. The species is solely known from the Early Eocene sediments exposed in Katmai National Park and Preserve, Kodiak Island Borough, Alaska...
from the Early Eocene sediments of the Paleocene-Eocene West Foreland Formation. In their type description Wolfe and Tanai designated A. alaskense as the type and only species for the extinct Acer section Alaskana.