Metasequoia occidentalis Temporal range: | |
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Metasequoia occidentalis foliage; early Paleocene, Alberta, Canada | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Gymnosperms |
Division: | Pinophyta |
Class: | Pinopsida |
Order: | Cupressales |
Family: | Cupressaceae |
Genus: | Metasequoia |
Species: | †M. occidentalis |
Binomial name | |
†Metasequoia occidentalis | |
Synonyms | |
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Metasequoia occidentalis is an extinct redwood species of the family Cupressaceae that is found as fossils throughout the Northern Hemisphere. It is one of three extinct species of Metasequoia that are currently recognized as valid. [2] [3]
The species was first described in 1863 from fossils found in the outcrops of the Late Paleocene-Middle Eocene Chuckanut Formation around Birch Bay, Washington. The species was originally described as Taxodium occidentale by John Strong Newberry. Fossilized Metasequoia-like remains were noted in Europe and North America from the 1800s on, but were assigned to the cupressaceous genera Sequoia (redwoods) and Taxodium (bald cypresses). It was not until the living species Metasequoia glyptostroboides was discovered and described from a remote area of China during the 1940s, that the affinity of many of the fossils became apparent. [4] [5] In 1951, the species was reassigned to Metasequoia as M. occidentalis by Ralph Works Chaney based on the close resemblance to living Metasequoia. [1] With a few notable exceptions, it has been claimed that the majority of the fossils documented in the literature show that M. occidentalis was indistigushable from living M. glyptostroboides. [6]
Like living Metasequoia, M. occidentalis was deciduous. The foliage consists of branchlets with oppositely arranged leaves. The leaves are ovate to linear in shape, ranging from 6–25 mm (0.24–0.98 in) in length and 1–2 mm (0.039–0.079 in) in width, with a distinct midvein, a petiolate base, and an acute tip. The seed-bearing cones are globose to ovoid, 11–40 mm (0.43–1.57 in) long and 6–34 mm (0.24–1.34 in) wide, with decussately arranged triangular scales, and are borne on long, leafless stalks. The seeds have two wings, are ovoid to cordate in shape, and are up to 5 mm (0.20 in) long and 4 mm (0.16 in) wide. The pollen-bearing cones are small, globose to ovoid, 1–5 mm (0.039–0.197 in) long and 0.5–4 mm (0.020–0.157 in) wide, and oppositely arranged on specialized stalks with one terminal cone. [2] [3]
Metasequoia occidentalis appeared in fossil record during the Late Cretaceous epoch (Cenomanian stage). By the Tertiary period, it had become a major constituent of lowland and swampy forests in the northern circum-Pacific and polar regions, where it commonly coexisted with Glyptostrobus europaeus . Fossils assignable to M. occidentalis have been reported from parts of the United States, Canada, Russia, China, Japan, Greenland and Svalbard, but Metasequoia appears to have been rare or absent in much of Europe. [6]
Sequoiadendron giganteum, also known as the giant sequoia, giant redwood or Sierra redwood is a coniferous tree, classified in the family Cupressaceae in the subfamily Sequoioideae. Giant sequoia specimens are the most massive trees on Earth. They occur naturally only in groves on the western slopes of the Sierra Nevada mountain range of California.
Metasequoia, or dawn redwood, is a genus of fast-growing deciduous trees, one of three species of conifers known as redwoods. The living species Metasequoia glyptostroboides is native to Lichuan county in Hubei province, China. Although the shortest of the redwoods, it grows to at least 165 feet in height. Local villagers refer to the original tree from which most others derive as Shuǐshān (水杉), or "water fir", which is part of a local shrine. Since its rediscovery in 1944, the dawn redwood has become a popular ornamental, with examples found in various parks in a variety of countries.
Metasequoia glyptostroboides, the dawn redwood, is a fast-growing, endangered deciduous conifer. It is the sole living species of the genus Metasequoia, one of three genera in the subfamily Sequoioideae of the family Cupressaceae. It now survives in the wild only in wet lower slopes and montane river and stream valleys in the border region of Hubei and Hunan provinces and Chongqing municipality in south-central China, notably in Lichuan county in Hubei. Although the shortest of the redwoods, it can grow to 167 ft (51 m) in height.
Cupressaceae is a conifer family, the cypress family, with worldwide distribution. The family includes 27–30 genera, which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdioecious or (rarely) dioecious trees and shrubs up to 116 m (381 ft) tall. The bark of mature trees is commonly orange- to red-brown and of stringy texture, often flaking or peeling in vertical strips, but smooth, scaly or hard and square-cracked in some species.
Chamaecyparis pisifera is a species of false cypress, native to central and southern Japan, on the islands of Honshū and Kyūshū.
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 Laos near the Vietnam border.
Glyptostrobus pensilis, known in Chinese as 水松, and also Chinese swamp cypress, is an endangered conifer, and the sole living species in the genus Glyptostrobus.
Athrotaxis is a genus of two to three species of conifers in the cypress family, Cupressaceae. The genus is endemic to western Tasmania, where they grow in high-elevation temperate rainforests.
The Chester M Alter Arboretum is an arboretum located on the campus of the University of Denver, 2467 South Vine Street, Denver, Colorado.
Tsuga chinensis, commonly referred to as the Taiwan or Chinese hemlock, or in Chinese as tieshan, is a coniferous tree species native to China, Taiwan, Tibet and Vietnam. The tree is quite variable and has many recognised varieties, though some are also maintained to be separate species by certain authorities. The tree was recently discovered in the mountains of northern Vietnam, making that the southernmost extension of its range.
Sequoia sempervirens is the sole living species of the genus Sequoia in the cypress family Cupressaceae. Common names include coast redwood, coastal redwood, and California redwood. It is an evergreen, long-lived, monoecious tree living 1,200–2,200 years or more. This species includes the tallest living trees on Earth, reaching up to 115.9 m (380.1 ft) in height and up to 8.9 m (29 ft) in diameter at breast height. These trees are also among the longest-living organisms on Earth. Before commercial logging and clearing began by the 1850s, this massive tree occurred naturally in an estimated 810,000 ha along much of coastal California and the southwestern corner of coastal Oregon within the United States.
Sequoioideae, commonly referred to as redwoods, is a subfamily of coniferous trees within the family Cupressaceae. It includes the largest and tallest trees in the world. The subfamily achieved its maximum diversity during the Jurassic and Cretaceous periods.
Sequoia is a genus of redwood coniferous trees in the subfamily Sequoioideae of the family Cupressaceae. The only extant species of the genus is Sequoia sempervirens in the Northern California coastal forests ecoregion of Northern California and Southwestern Oregon in the United States. The two other genera in the subfamily Sequoioideae, Sequoiadendron and Metasequoia, are closely related to Sequoia. It includes the tallest trees, as well as the heaviest, in the world.
Metasequoia foxii is an extinct redwood species in the family Cupressaceae described from numerous fossils of varying growth stage. The species is solely known from the Paleocene sediments exposed in central Alberta, Canada. It is one of three extinct species belonging to the redwood genus Metasequoia.
Sequoia affinis is an extinct species of the genus Sequoia in the cypress family Cupressaceae.
Sequoiadendron is a genus of evergreen trees, with two species, only one of which survives to the present:
Glyptostrobus europaeus is an extinct conifer species of the family Cupressaceae that is found as fossils throughout the Northern Hemisphere. The sole living species of Glyptostrobus was described from China in 1926. The name of the genus comes from the Greek "glypto" meaning grooved or carved, and "strobilus" meaning cone. The species name "europaeus" refers to the fact that it was first described from Europe.
Ralph Works Chaney was an American paleobotanist. The standard author abbreviation R.W.Chaney is used to indicate this person as the author when citing a botanical name.
Metasequoia heerii is an extinct redwood species of the family Cupressaceae that is found as fossils throughout the Northern Hemisphere. It is one of several proposed extinct species of Metasequoia that were previously referred to Sequoia.
Taxodium dubium is an extinct species of cypress in the genus Taxodium in the family Cupressaceae which lived from the Late Paleocene to the Pliocene in North America and Europe. The species was first described in 1823 by Kaspar Maria von Sternberg.