Acer alaskense | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Sapindales |
Family: | Sapindaceae |
Genus: | Acer |
Section: | † Acer sect. Alaskana |
Species: | †A. alaskense |
Binomial name | |
†Acer alaskense Wolfe & Tanai, 1987 | |
Acer alaskense is an extinct maple species in the family Sapindaceae described from a fossil leaf. [1] 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. [1]
The species was described from a single full-leaf specimen found in the Chickaloon Formation, which underlies the Kenai Group 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 [2] with Acer alaskense known only from the latest Paleocene section exposed in the Even Jones coal mine. [1]
Acer alaskense was described from a solitary specimen, the holotype (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.. [1]
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. [1] 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. [1] In their type description Wolfe and Tanai designated A. alaskense as the type and only species for the extinct Acer section Alaskana. [1]
Leaves of Acer alaskense are simple in structure and generally oval in shape. The leaves are three- to possibly only two-lobed, with the fossil showing a blade with one lateral lobe. The leaf is 8.0 centimetres (3.1 in) wide and 10.5 centimetres (4.1 in) long in overall dimension. A. alaskense has a simple structure to the tertiary veins that connect the basal secondary veins, which is not seen in other species of Acer. However the numerous teeth and structure of the areolar venation are very similar to the modern species A. spicatum . [1] Wolfe and Tanai note that the apparent two-lobed structure may be an aberration and A. alaskense may have typically been three-lobed. [1]
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. It is the type species for the extinct section Douglasa.
Acer stonebergae is an extinct maple species in the family Sapindaceae described from two fossil samaras. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States, and the adjacent area of south central British Columbia, Canada. It is one of three species belonging to the extinct section Torada.
Acer toradense is an extinct maple species in the family Sapindaceae described from two fossil samaras. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States, and the adjacent area of south central British Columbia, Canada. It is one of three species belonging to the extinct section Torada.
Acer washingtonense is an extinct maple species in the family Sapindaceae described from one fossil leaf and four fossil samaras. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States. It is one of three species belonging to the extinct section Torada.
Acer stewarti is an extinct maple species in the family Sapindaceae described from a series of fossil leaves and samaras. The species is solely known from the Early Eocene sediments exposed in south central British Columbia, Canada adjacent to northeast Washington state, United States. It is one of only two species belonging to the extinct section Stewarta.
Acer browni is an extinct maple species in the family Sapindaceae described from a series of isolated fossil leaves and samaras. The species is known from the early to middle Miocene sediments exposed in Western Oregon, Washington state, USA and Northern Graham Island, Haida Gwaii, Canada. It is one of several extinct species placed in the living section Parviflora.
Acer smileyi is an extinct maple species in the family Sapindaceae described from a series of isolated fossil leaves and samaras. The species is known from the late Oligocene to middle Miocene sediments exposed in the states of Alaska, Idaho, Nevada, and Oregon, USA. It is one of several extinct species placed in the living section Parviflora.
Acer republicense is an extinct maple species in the family Sapindaceae described from a single fossil samara. The species is solely known from the Early Eocene sediments exposed in northeast Washington state, United States. It is the only species belonging to the extinct section Republica.
Acer ashwilli is an extinct maple species in the family Sapindaceae described from a group of fossil leaves and samaras. The species is solely known from the Early Oligocene sediments exposed in central Oregon, USA. It is one of several extinct species belonging to the living section Ginnala.
Acer clarnoense is an extinct maple species in the family Sapindaceae described from a series of isolated fossil leaves and samaras. The species is known from the late Eocene sediments exposed in the state of Oregon in the US. It is one of several extinct species placed in the living section Macrantha.
Acer dettermani is an extinct maple species in the family Sapindaceae described from a series of isolated fossil leaves. The species is known from the late Eocene to early Oligocene sediments exposed in the state of Alaska, USA. It is one of several extinct species placed in the living section Macrantha.
Acer castorrivularis is an extinct maple species in the family Sapindaceae described from a solitary fossil leaf. The species is known from the latest Eocene sediments exposed in the state of Montana, USA. It is one of several extinct species placed in the living section Macrantha.
Acer latahense is an extinct maple species in the family Sapindaceae described from series of isolated fossil leaves. The species is known from the latest early to middle Miocene sediments exposed in the states of Oregon and Washington, USA. It is one of several extinct species placed in the living section Macrantha.
Acer palaeorufinerve is an extinct maple species in the family Sapindaceae described from series of isolated fossil samaras and leaves. The species was described from Miocene to Pliocene aged fossils found in Japan and is known from Korean fossils and Miocene sediments exposed in the state of Alaska, USA. It is one of several extinct species placed in the living section Macrantha.
Acer ivanofense is an extinct maple species in the family Sapindaceae described from series of isolated fossil leaves. The species was described from Eocene to Oligocene aged fossils found in the United States of America. It is one of several extinct species placed in the living section Glabra.
Acer kenaicum is an extinct maple species in the family Sapindaceae described from a pair of fossil leaves and a samara. The species is known solely from the Oligocene sediments found exposed in central coastal Alaska, US. It is one of several extinct species belonging to the living section Rubra.
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.
Acer taggarti is an extinct maple species in the family Sapindaceae described from a number of fossil leaves and samaras. The species is known from Miocene sediments exposed in central Oregon, US. It is one of several extinct species belonging to the living section Rubra.
Acer ferrignoi is an extinct maple species in the family Sapindaceae described from a group of fossil leaves. The species is known from Miocene sediments exposed in Oregon, US. It is one of several extinct species belonging to the living section Rubra.
Acer eonegundo is an extinct maple species in the family Sapindaceae described from a single partial fossil leaf. The species is known from Eocene sediments exposed in the US state of Nevada. It is placed into the living Acer section Negundo.