Dipteronia brownii Temporal range: | |
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Dipteronia brownii mericarp Klondike Mountain Formation | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Sapindales |
Family: | Sapindaceae |
Genus: | Dipteronia |
Species: | D. brownii |
Binomial name | |
Dipteronia brownii McClain & Manchester, 2001 | |
Dipteronia brownii is an extinct species in the soapberry family (Sapindaceae) described in 2001. Fossils of D. brownii are known from stratigraphic formations in North America and Asia ranging in age between Paleocene to Early Oligocene.
The oldest occurrences for Dipteronia brownii are both Paleogene in age, with fossils found in the Middle Paleocene, 63 to 60 million years ago Fort Union Formation of Wyoming [1] and the Danian Middle-Upper Tsagayan Formation of Northeastern coastal Russia. [2] Migration between the slightly older Russian Far East site and North America was likely facilitated by the Beringian land bridge during the early to middle Paleoene. [3]
In the Early Eocene the species expanded into the Eocene Okanagan Highlands sites of East central British Columbia and north east central Washington. Fossils have been found in the Okanagan highlands formations from the southern most Klondike Mountain Formation to the northern most Driftwood Shales, with occurrences in the Allenby Formation, Tranquille Formation, Chu Chua Formation and Horsefly Shales. [1]
During the Middle Eocene the species appears in the John Day Formation of central Oregon. During the middle to late Eocene the species spread east and south to the Ruby Basin Flora of Montana and the Florissant Formation of Colorado, while the last North American occurrence is in the Early Oligocene, Rupelian [4] of upper John Day Formations Bridge Creek Flora. [1] Concurrently, Dipteronia brownii fruits are also found in Rupelian 32 ± 1 million years ago lacustrine mudstones of Chuxiong Yi Autonomous Prefecture southwestern China, and are also the southern most of the D. brownii fossils. [3]
Ding et al. (2018) posited that the reduction of Dipteronia from the broad North American and wide Asian range seen in D. brownii to the isolated regional endemic of modern times seen in Dipteronia dyeriana and Dipteronia sinensis was the result of several factors. Range reduction was likely due to overall global cooling during the Oligocene and Miocene, combined with increased and intensified rain fall in the northern hemisphere and associated high latitude drying. [3]
Roland Brown (1935) described the Dipteronia species Dipteronia americana based on both fruits and leaflets [5] including one pair of leaflets first figured by Edward Berry (1929). [6] The species was redescribed by Jack Wolfe and Wesley Wehr (1987) who designated the leaflet as lectotype for the species, which they moved to the new extinct genus Bohlenia based on the difference in leaflet venation from that of other sapindalian taxa. [7]
Manchester (1999) figured a single Dipteronia mericarp fossil which was at that time identified as being from the Eocene Fushun Formation in Liaoning Province, China. The location was taken from the specimen drawer in the University of California Museum of Paleontology collections where the fossil was stored; however, the fossil itself did not have a label indicating its location. [8] Doubt was later raised regarding the provenance of the fossil, with Manchester being informed that the UCMP formerly housed collections of very similarly colored shale from the Chu Chua Formation near Joseph Creek, British Columbia. The Chu Chua fossils had been transferred to the Geological Survey of Canada collections in the 1970's, but it was possible the Dipteronia specimen was left behind. [1] Palynological analysis of pollen in the specimen matrix was performed in October 2000 in conjunction with the Manchester (2001) research as an attempt to determine the origin site. [1] Based on pollen analysis of Fushun shale, Chu Chua shale and the specimen, much of the palynofloras overlapped. However the palynomorphs Liquidambarpollenites and Ephedripites were only seen in Fushun samples and not the Chu Chua or the mystery sample. Additionally though no other Dipteronia have been identified in Joseph Creek collections, the genus is present at coeval locations elsewhere in the Eocene Okanagan Highlands, leading Manchester (2001) to place the fossil as Joseph Creek, and state Dipteronia was not present in the Fushun Flora. [1]
The North American Dipteronia fossils were reexamined and redescribed by Amy McClain and Steven Manchester, whose 2001 type description for Dipteronia brownii was published in the American Journal of Botany . [1] McClain and Manchester noted the lack of attachment fossils uniting the Bohlenia americana leaflets to fruits, and as such opted to remove the fruits from Bohlenia and restrict the taxon definition to only foliage. They opted to name the new fruit species D. brownii as a patronym honoring Roland Brown as the first systematist to recognize Dipteronia fossils. [1]
Dipteronia brownii fruits were born in schizocarp comprised of three, and less commonly two, flat mericarps which attach along a straight proximal edge. The schizocarps were born on long thin pedicels which flared to a disk-shaped juncture with the perianth. The mericarps have a circular smooth outline, extending from the proximal attachment scar, giving a subelliptical profile to the 8–24 mm (0.3–0.9 in) wing. [1] A single primary vein runs 1.6–5.6 mm (0.1–0.2 in) from the pedicel up the attachment scar before turning inward at a 90–135° angle towards the center of the wing. In the central area of the wing, 2–8 mm (0.1–0.3 in) from the wing edge, is a pyriform to elliptical seed with a diameter of 3–8 mm (0.1–0.3 in). Covering the surface of the seed pericarp is a reticulated network of secondary veins. The tertiary veins spreading out from the seed though the wing split and join as they extend to the wing margin. connecting the tertiaries is a fine reticulum of quaternary veins which form polygonal areoles. [1]
Dipteronia is a genus with two living and one extinct species in the soapberry family Sapindaceae. The living species are native to central and southern China, The fossil species has been found in Middle Paleocene to Early Oligocene sediments of North America and China.
Driftwood Canyon Provincial Park is a provincial park in British Columbia, Canada. Driftwood Canyon Provincial Park covers 23 ha of the Bulkley River Valley, on the east side of Driftwood Creek, a tributary of the Bulkley River, 10 km northeast of the town of Smithers. The park is accessible from Driftwood Road from Provincial Highway 16. It was created in 1967 by the donation of the land by the late Gordon Harvey (1913–1976) to protect fossil beds on the east side of Driftwood Creek. The beds were discovered around the beginning of the 20th century. The park lands are part of the asserted traditional territory of the Wet'suwet'en First Nation.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 1935.
Florissantia is an extinct genus of flowering plants in the Malvaceae subfamily Sterculioideae known from western North America and far eastern Asia. Flower, fruit, and pollen compression fossils have been found in formations ranging between the Early Eocene through to the Early Oligocene periods. The type species is Florissantia speirii and three additional species are known, Florissantia ashwillii, Florissantia quilchenensis, and Florissantia sikhote-alinensis.
The Klondike Mountain Formation is an Early Eocene (Ypresian) geological formation located in the northeast central area of Washington state. The formation is comprised of volcanic rocks in the upper unit and volcanic plus lacustrine (lakebed) sedimentation in the lower unit. the formation is named for the type location designated in 1962, Klondike Mountain northeast of Republic, Washington. The formation is a lagerstätte with exceptionally well-preserved plant and insect fossils has been found, along with fossil epithermal hot springs.
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.
The McAbee Fossil Beds is a Heritage Site that protects an Eocene Epoch fossil locality east of Cache Creek, British Columbia, Canada, just north of and visible from Provincial Highway 97 / the Trans-Canada Highway. The McAbee Fossil Beds, comprising 548.23 hectares, were officially designated a Provincial Heritage Site under British Columbia's Heritage Conservation Act on July 19, 2012. The site is part of an old lake bed which was deposited about 52 million years ago and is internationally recognised for the diversity of plant, insect, and fish fossils found there. Similar fossil beds in Eocene lake sediments, also known for their well preserved plant, insect and fish fossils, are found at Driftwood Canyon Provincial Park near Smithers in northern British Columbia, on the Horsefly River near Quesnel in central British Columbia, and at Republic in Washington, United States. The Princeton Chert fossil beds in southern British Columbia are also Eocene, but primarily preserve an aquatic plant community. A 2016 review of the early Eocene fossil sites from the interior of British Columbia discusses the history of paleobotanical research at McAbee, the Princeton Chert, Driftwood Canyon, and related Eocene fossil sites such as at Republic.
The Allenby formation is a sedimentary rock formation in British Columbia which was deposited during the Ypresian stage of the Early Eocene. It consists of conglomerates, sandstones with interbedded shales and coal. The shales contain an abundance of insect, fish and plant fossils known from 1877 and onward, while the Princeton Chert was first indented in the 1950's and is known from anatomically preserved plants.
Rhus malloryi is an extinct species of flowering plant in the sumac family Anacardiaceae. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States. The species was first described from a series of isolated fossil leaves in shale. R. malloryi is one of four sumac species to be described from the Klondike Mountain Formation, and forms a hybrid complex with the other three species.
The Coldwater Beds are a geologic formation of the Okanagan Highlands in British Columbia, Canada. They preserve fossils dating back to the Ypresian stage of the Eocene period, or Wasatchian in the NALMA classification.
Langeria is an extinct genus of flowering plants in the family Platanaceae containing the solitary species Langeria magnifica. Langeria is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States and similar aged formations in British Columbia, Canada.
Ulmus okanaganensis is an extinct species of flowering plant in the family Ulmaceae related to the modern elms. The species is known from fossil leaves, flowers, and fruits found in the early Eocene deposits of northern Washington state, United States and similar aged formations in British Columbia, Canada.
Tetracentron hopkinsii is an extinct species of flowering plant in the family Trochodendraceae. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States and south Central British Columbia. The species was first described from fossil leaves found in the Allenby Formation. T. hopkinsii are possibly the leaves belonging to the extinct trochodendraceous fruits Pentacentron sternhartae.
Comptonia columbiana is an extinct species of sweet fern in the flowering plant family Myricaceae. The species is known from fossil leaves found in the early Eocene deposits of central to southern British Columbia, Canada, plus northern Washington state, United States, and, tentatively, the late Eocene of Southern Idaho and Earliest Oligocene of Oregon, United States.
The paleoflora of the Eocene Okanagan Highlands includes all plant and fungi fossils preserved in the Eocene Okanagan Highlands Lagerstätten. The highlands are a series of Early Eocene geological formations which span an 1,000 km (620 mi) transect of British Columbia, Canada and Washington state, United States and are known for the diverse and detailed plant fossils which represent an upland temperate ecosystem immediately after the Paleocene-Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1880-90s on British Columbian sites, and 1920-30s for Washington sites. A returned focus and more detailed descriptive work on the Okanagan Highlands sites revived in the 1970's. The noted richness of agricultural plant families in Republic and Princeton floras resulted in the term "Eocene orchards" being used for the paleofloras.
Fagus langevinii is an extinct species of beech in the family Fagaceae. The species is known from fossil fruits, nuts, pollen, and leaves found in the early Eocene deposits of South central British Columbia, and northern Washington state, United States.
The Eocene Okanagan Highlands or Eocene Okanogan Highlands are a series of Early Eocene geological formations which span a 1,000 km (620 mi) transect of British Columbia, Canada, and Washington state, United States. Known for a highly diverse and detailed plant and animal paleobiota the paleolake beds as a whole are considered one of the great Canadian Lagerstätten. The paleobiota represented are of an upland subtropical to temperate ecosystem series immediately after the Paleocene–Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1870–1920s on British Columbian sites, and 1920–1930s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highland sites started in the late 1960s.
Ulmus chuchuanus is an extinct species of flowering plant in the family Ulmaceae related to the modern elms. The species is known from fossil leaves and fruits found in early Eocene sites of northern Washington state, United States and central British Columbia, Canada.
Alnus parvifolia is an extinct species of flowering plant in the family Betulaceae related to the modern birches. The species is known from fossil leaves and possible fruits found in early Eocene sites of northern Washington state, United States, and central British Columbia, Canada.