Sequoiadendron chaneyi
Encyclopedia
Sequoiadendron chaneyi is an extinct species
of tree in the Cupressaceae
genus Sequoiadendron
. Known from Miocene
fossils found in Nevada and California, S. chaneyi is the oldest species of Sequoiadendron. The common use of the name "sequoia" generally refers to Sequoiadendron, which occurs naturally only in the various groves that exist on the western slopes of the Sierra Nevada mountains of California. S. chaneyi is considered the probable direct ancestor to the extant Sequoiadendron giganteum.
. The area of the Middlegate basin is preserved as the Middlegate and Eastgate Formations, which grew along the shores of an ancient lake. While S. chaneyi is found in both formations, it is much rarer in the Middlegate formation, which was a south-facing scrubland-type ecosystem, being represented by only a few twiglets with foliage. In contrast, S. chaneyi is abundant in the Eastgate formation, which was a north-facing forested setting of hills and valleys, being represented by abundant foliage and several cones. Specimens figured as Glyptostrobus
by Jack Wolfe
in 1964 from the Middlegate basin were re-identified by Daniel Axelrod
in 1985 as S. chaneyi, based on morphology and the presence of cones in the same deposits.
Fossils of S. chaneyi have been found in the late Miocene Relief Peak Formation of Alpine County, California
. The fossils are found in the topmost section of the Relief Peak Formation at the contact of the formation and the Mount Reba Conglomerate. The stratigraphy and composition of formations indicate that the fossils of the Mount Reba flora were deposited in a low, broad valley environment that drained southwesterly and was exposed to the storm track. While present in the flora, S. chaneyi was a very rare component of it, being known from only three foliage specimens. The specimens were most likely transported downstream from the site where the trees were growing.
S. chaneyi is known from the Middle Miocene Chloropagus Formation deposits of Storey County, Nevada
, west of Fernley, Nevada
. While the fossils are locally abundant at several of the Purple Mountain flora sites, it is found as a component at most of the sites. The higher concentrations seem to be associated with those deposits which were formed in mesic bottomlands.
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...
of tree in the Cupressaceae
Cupressaceae
The Cupressaceae or cypress family is a conifer family with worldwide distribution. The family includes 27 to 30 genera , which include the junipers and redwoods, with about 130-140 species in total. They are monoecious, subdioecious or dioecious trees and shrubs from 1-116 m tall...
genus Sequoiadendron
Sequoiadendron
Sequoiadendron giganteum is the sole living species in the genus Sequoiadendron, and one of three species of coniferous trees known as redwoods, classified in the family Cupressaceae in the subfamily Sequoioideae, together with Sequoia sempervirens and...
. Known from Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
fossils found in Nevada and California, S. chaneyi is the oldest species of Sequoiadendron. The common use of the name "sequoia" generally refers to Sequoiadendron, which occurs naturally only in the various groves that exist on the western slopes of the Sierra Nevada mountains of California. S. chaneyi is considered the probable direct ancestor to the extant Sequoiadendron giganteum.
Occurrences
Fossils of Sequoiadendron chaneyi have been described from the Middle Miocene floras found in the area of Middlegate Basin in Churchill County, NevadaChurchill County, Nevada
Churchill County is a county located in the western U.S. state of Nevada. As of the 2000 census, the population was 23,982. As of July 1, 2007, the population of Churchill County was estimated at 27,190. The county, named after Mexican-American War hero brevet Brigadier General Sylvester Churchill,...
. The area of the Middlegate basin is preserved as the Middlegate and Eastgate Formations, which grew along the shores of an ancient lake. While S. chaneyi is found in both formations, it is much rarer in the Middlegate formation, which was a south-facing scrubland-type ecosystem, being represented by only a few twiglets with foliage. In contrast, S. chaneyi is abundant in the Eastgate formation, which was a north-facing forested setting of hills and valleys, being represented by abundant foliage and several cones. Specimens figured as Glyptostrobus
Glyptostrobus
Glyptostrobus, is a small genus of conifers in the family Cupressaceae. The sole living species, Glyptostrobus pensilis, is native to subtropical southeastern China, from Fujian west to southeast Yunnan, and also very locally in northern Vietnam and Borikhamxai Province of eastern Lao PDR near the...
by Jack 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:...
in 1964 from the Middlegate basin were re-identified by Daniel Axelrod
Daniel I. Axelrod
Daniel Isaac Axelrod was a leading twentieth-century paleoecologist specializing in Tertiary Cordilleran floras, in particular correlating fossil evidence of specific floras with climate change indicators.-Biography:...
in 1985 as S. chaneyi, based on morphology and the presence of cones in the same deposits.
Fossils of S. chaneyi have been found in the late Miocene Relief Peak Formation of Alpine County, California
Alpine County, California
Alpine County is the smallest county, by population, in the U.S. state of California. As of 2010, it had a population of 1,175, all rural. There are no incorporated cities in the county. The county seat is Markleeville...
. The fossils are found in the topmost section of the Relief Peak Formation at the contact of the formation and the Mount Reba Conglomerate. The stratigraphy and composition of formations indicate that the fossils of the Mount Reba flora were deposited in a low, broad valley environment that drained southwesterly and was exposed to the storm track. While present in the flora, S. chaneyi was a very rare component of it, being known from only three foliage specimens. The specimens were most likely transported downstream from the site where the trees were growing.
S. chaneyi is known from the Middle Miocene Chloropagus Formation deposits of Storey County, Nevada
Storey County, Nevada
Storey County is a county located in the U.S. state of Nevada. As of the 2000 census, the population was 3,399, which was estimated to have risen to 4,110 in 2006...
, west of Fernley, Nevada
Fernley, Nevada
Fernley is a city in Lyon County, Nevada, United States, within Reno-Sparks-Lake Tahoe metropolitan. The city incorporated in 2001, including land in Washoe County; prior to that it was a census-designated place . The population of the CDP was 8,543 at the 2000 census; the city itself had an...
. While the fossils are locally abundant at several of the Purple Mountain flora sites, it is found as a component at most of the sites. The higher concentrations seem to be associated with those deposits which were formed in mesic bottomlands.