Hiodon woodruffi Temporal range: Ypresian | |
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Hiodon woodruffi fossil SRIC collection | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Hiodontiformes |
Family: | Hiodontidae |
Genus: | Hiodon |
Species: | †H. woodruffi |
Binomial name | |
†Hiodon woodruffi (Wilson, 1978) | |
Synonyms | |
Eohiodon woodruffiWilson, 1978 |
Hiodon woodruffi is an extinct species of bony fish in the mooneye family, Hiodontidae. The species is known from fossils found in the early Eocene deposits of northern Washington state in the United States and late Eocene deposits in northwestern Montana. The species was first described as Eohiodon woodruffi. H. woodruffi is one of two Eocene Okanagan Highlands mooneye species, and one of five fish identified in the Klondike Mountain Formation.
Hiodon woodruffi fossils have been recovered from two locations in the Okanagan highlands, the Horsefly shale near Horsefly, British Columbia and the several exposures of the Klondike Mountain Formation in northern Ferry County, Washington. Both sites represent upland lake systems that were surrounded by a warm temperate ecosystem with nearby volcanism. [1] The highlands likely had a mesic upper microthermal to lower mesothermal climate, in which winter temperatures rarely dropped low enough for snow, and which were seasonably equitable. [2]
The Okanagan highlands paleoforest surrounding the lakes have been described as precursors to the modern temperate broadleaf and mixed forests of Eastern North America and Eastern Asia. Based on the fossil biotas the lakes were higher and cooler then the coeval coastal forests preserved in the Puget Group and Chuckanut Formation of Western Washington, which are described as lowland tropical forest ecosystems. Estimates of the paleoelevation range between 0.7–1.2 km (0.43–0.75 mi) higher than the coastal forests. This is consistent with the paleoelevation estimates for the lake systems, which range between 1.1–2.9 km (1,100–2,900 m), which is similar to the modern elevation 0.8 km (0.50 mi), but higher. [2]
Estimates of the mean annual temperature have been derived from climate leaf analysis multivariate program (CLAMP) analysis of the Republic paleoflora, and leaf margin analysis (LMA) of both the Horsefly and Republic paleofloras. The CLAMP results after multiple linear regressions for Republic gave a mean annual temperature of approximately 8.0 °C (46.4 °F), while the LMA gave 9.2 ± 2.0 °C (48.6 ± 3.6 °F). LMA of the Horsefly flora returned a mean annual temperature of 10.4 ± 2.2 °C (50.7 ± 4.0 °F). This is lower than the mean annual temperature estimates given for the coastal Puget Group, which is estimated to have been between 15–18.6 °C (59.0–65.5 °F). The bioclimatic analysis for Republic and Horsefly suggest mean annual precipitation amounts of 115 ± 39 cm (45 ± 15 in) and 105 ± 47 cm (41 ± 19 in) respectively. [2]
When the first fossils were collected the Klondike Mountain formation was thought to be late Oligocene in age. Potassium-argon radiometric dating of samples taken near the Tom Thumb mine in 1966 resulted in a tentative 55 million years old age. Further refinement of sample dating has yielded an approximately Early Eocene, Ypresian age, being radiometrically dated as 49.4 million years old. [2]
The Kishenehn Formation conservat lagerstätte [3] in Northwestern Montana has been dated to approximately 46.02 million years old [4] based on potassium-argon of the Coal Creek member. [5]
The earliest find, which were later identified as H. woodruffi, were specimens collected by Canada's first vertebrate paleontologist Lawrence Lambe in 1906 from Horsefly. [6]
Fossils of Hiodon woodruffi were first collected in the Klondike Mountain Formation of Washington in the 1960s. One set of fish was collected from the Toroda Creek Graben northwest of Republic by R. C. Pearson, and tentatively identified by paleoichthyologist David Dunkle as members of several genera including the Aphredoderid Tricophanes . Pearson sent almost all of the specimens collected to the Smithsonian, but the fossils were never accessioned into the collections and are now considered lost. Pearson did retain one "Tricophanes" fossil from the initial collection which was later donated to the USGS collections. [7] During the same decade, a collection of fish from near the Tom Thumb Mine in Republic was compiled by the young [8] resident R. Woodward. This collection was subsequently donated to the University of Alberta paleontology department by Woodward's family in 1977. During the summers of 1976 and 1977 the University of Alberta also conducted field collecting in both the Toroda Creek and Republic areas, yielding a number of fossil fish material, including a single hiodontid. [7]
The Okanagan highland hiodontid fossils were studied in detail by paleoichthyologist Mark Wilson, of the University of Alberta, with a monograph overview of the British Columbian Eocene fish fauna and redescription of H. rosei being published in 1977, [9] followed by a smaller paper in 1978 containing the H. woodruffi description. [7] The type description of H.woodruffi was published in the May 1978 issue of the Canadian Journal of Earth Sciences. The etymology of the species name woodruffi was chosen in recognition of the Woodruff family for the collection and donation of the specimens studied. Wilson designated University of Alberta specimen UA 13227A & 13227B, collected during the 1976 field work at the Tom Thumb mine as the holotype [7] and also designated a series of topotype specimens in the type series. Specimens UA 13241, 13244, 13250, 13262 and 1326 were all collected by R. Woodruff, while specimen UA 13225 was collected during the 1976 field season. Additionally Wilson referred a group of other specimens to the species which were not included in the type series including four specimens from Horsefly and USGS El-2185, the Tricophanes fossil collected by Pearson in the 1960s. [7] H. woodruffi coexisted with four other fish species in the Klondike Mountain Formation lake system. [10] [11]
A reassessment and redescription of Hiodontidae was completed by Hilton and Grande in 2008. They noted that the known osteological morphology range of the species assigned to Eohiodon were within the osteology spectrum seen in modern Hiodon individuals. This merging of Eohiodon into Hiodon resulted in the species being moved to Hiodon woodruffi as the accepted binomial. [12] Hilton and Grande examined specimens from the Okanagan Highlands as well as specimens referred to the species which had been found in the Kishenehn Formation, and noted that the proposed merging of Hiodon falcatus from the Green River Formation was not accepted, based on differences in osteology. [12]
Based on the consistent preservation of specimens in lateral views, Wilson determined that both young and adult H. woodruffi specimens had laterally compressed bodies. At the time of description the one complete adult male had a body length of 108 mm (4.3 in), with the species having a hypothetical upper length of 110 mm (4.3 in). The holotype fish was suggested to be either an adult female or immature large male, based on the lack of expanded anal rays. There are between 47 and 49 total vertebrae, of which 24 to 25 are caudal and 22 to 24 are precaudal vertebrae. Scales are sparse, with a rounded outline and have parallel furrows along the front edges. [7]
Adults of Hiodon woodruffi have between 12 and 13 rays in the pectoral fins, based on the six observed specimens. The pelvic fins have about 7 total rays, and extend to down the body 2/3 of the way to the anus, starting just to the front of where the anal fin starts, and extending towards the tail ending above the rear third of the anal fin. With a triangular outline, the dorsal fin is composed of 13 to 15 branching rays each attached to a vertebra, and the rear most ray is double branched. The anal fin has 17-18 branched rays, one unbranched ray, and several rudimentary rays giving a slightly concave outline on the holotype, but on mature males, thickening of the frontal 10 rays gives a rounded fin outline. The caudal fin has eight branching rays above the fishes midline, and another eight rays below. The fin is emarginate, with the upper and lower rays extending outwards and dipping back in to meet closer to the body in the central section of fin. The fin tips and center fork are all gently rounded. [7]
Hiodon woodruffi are noted to be larger at maturity then the coeval H. rosei, with more anal rays, and a longer length at maturity. Mature male H. rosei specimens average 50 mm (2.0 in), H. woodruffi males are am average of 108 mm (4.3 in), while the living Hiodon alosoides and Hiodon tergisus males average 250 mm (9.8 in). [7]
Hiodontiformes is an order of ray-finned fish consisting of the two living species of the mooneye family, Hiodontidae, and three extinct genera.
Hiodontidae, commonly called mooneyes, is a family of ray-finned fish with a single included genus Hiodon. The genus comprise two living species native to North America and three to five extinct species recorded from Paleocene to Eocene age fossils. They are large-eyed, fork-tailed fish that superficially resemble shads. The vernacular name comes from the metallic shine of their eyes.
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 from 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.
Amyzon is an extinct genus belonging to the sucker family Catostomidae first described in 1872 by E. D. Cope. There are six valid species in the genus. Amyzon are found in North American fossil sites dated from the Early Eocene in Montana and Washington USA, as well as the British Columbian sites at McAbee Fossil Beds, Driftwood Canyon, and the "Horsefly shale", as well as Early Oligocene sites in Nevada USA. One Middle Eocene species is known from the Xiawanpu Formation of China. The Ypresian species A. brevipinne of the Allenby Formation was redescribed in 2021 and moved to a separate monotypic genus Wilsonium.
Tilia johnsoni is an extinct species of flowering plant in the family Malvaceae that, as a member of the genus Tilia, is related to modern lindens. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States and a similar aged formation in British Columbia, Canada.
Dinokanaga is a small genus of scorpionfly belonging to the extinct family Dinopanorpidae. The six species D. andersoni, D. dowsonae, D. hillsi, D. sternbergi, D. webbi, and D. wilsoni have all been recovered from Eocene fossil sites in British Columbia, Canada, and Washington state, United States.
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.
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 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.
Amia? hesperia is an extinct species of bony fish in the bowfin family, Amiidae. The species is known from fossils found in the early Eocene deposits of northern Washington state in the United States and southeastern British Columbia. The species is one of eight fish species identified in the Eocene Okanagan Highlands paleofauna.
Barghoornia is an extinct genus of flowering plants in the family Burseraceae containing the solitary species Barghoornia oblongifolia. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, 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.
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.
The paleofauna of the Eocene Okanagan Highlands consists of Early Eocene arthropods, vertebrates, plus rare nematodes and molluscs found in geological formations of the northwestern North American Eocene Okanagan Highlands. The highlands lake bed series' as a whole are considered one of the great Canadian Lagerstätten. The paleofauna represents that of a late Ypresian 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. Focus and more detailed descriptive work on the Okanagan Highlands site started in the last 1970's. Most of the highlands sites are preserved as compression-impression fossils in "shales", but also includes a rare permineralized biota and an amber biota.
Eoseira is an extinct genus of diatoms belonging to the family Aulacoseiraceae and containing the single species Eoseira wilsonii. The species is dated to the Early Eocene Ypresian stage and has only been found at the type locality in east central British Columbia.
Alnus parvifolia was 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.
Plecia avus is an extinct species of Plecia in the March fly family Bibionidae and is solely known from Early Eocene sediments exposed in central southern British Columbia. The species is one of twenty bibionid species described from the Eocene Okanagan Highlands.
The Paleobiota of the Klondike Mountain Formation comprises a diverse suite of Early Eocene plants and animals recovered from North Central Washington State. The formation outcrops in locations across the north western area of Ferry County, with major sites in Republic, north west of Curlew Lake, and on the Toroda Creek area. The formation is the southern most of the Eocene Okanagan Highlands, sharing much of the paleoflora and paleofauna with site across Central and southern British Columbia.
Dennstaedtia christophelii is an extinct species of fern in the family Dennstaedtiaceae related to the modern hayscented ferns. The species is known from fossil fronds found in early Eocene sites of northern Washington state, United States and central British Columbia, Canada. The species is suggested to be closest to a Neotropical "Patania" clade and specifically the species Dennstaedtia producta and Dennstaedtia mathewsii.
Erismatopterus is an extinct genus of percopsiform fish which lived during the early to middle Eocene epoch and containing the single species Erismatopterus levatus. A report of the genus in sediments of similar age in Washington State have been discredited. Erismatopterus is treated as part of the family Percopsidae, but formerly was the type genus of the extinct family Erismatopteridae. The genus is closely related to Amphiplaga of related lake sediments. Shoaling behavior has been reported from a mass mortality fossil of E. levatus and attributed as a predator-evasion response behavior.