Utah roundmouth snail
Encyclopedia
The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species
of freshwater snail
with a gill and an operculum
, an aquatic
gastropod mollusk in the family Valvatidae
, the valve snails.
This species of snail is endemic to the United States
.
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
, Utah (the type locality
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
of the shell is obtusely elevated, and the apex
is depressed. The suture is well impressed. The aperture
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
of Utah
and in the Snake River
of southern Idaho
.
This snail is endemic to the Pliocene
of the Lake Idaho region.
The modern range of the snail extended as far downstream as Grandview
(rkm 783, rm
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
downstream to Burley
.
Recent surveys at The Nature Conservancy
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
, spring creeks and tributaries, the mainstem Snake River
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
, mud, or mud-sand substrate, among stream bed
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
(CaCO3) and silicon dioxide
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
(IPC) (1995-2002), IDFG, Idaho Transportation Department
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species
of freshwater snail
with a gill and an operculum
, an aquatic
gastropod mollusk in the family Valvatidae
, the valve snails.
This species of snail is endemic to the United States
.
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
, Utah (the type locality
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
of the shell is obtusely elevated, and the apex
is depressed. The suture is well impressed. The aperture
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
of Utah
and in the Snake River
of southern Idaho
.
This snail is endemic to the Pliocene
of the Lake Idaho region.
The modern range of the snail extended as far downstream as Grandview
(rkm 783, rm
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
downstream to Burley
.
Recent surveys at The Nature Conservancy
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
The Utah valvata snail persists in a variety of aquatic habitats, including cold-water springs
, spring creeks and tributaries, the mainstem Snake River
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
, mud, or mud-sand substrate, among stream bed
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
(CaCO3) and silicon dioxide
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
(IPC) (1995-2002), IDFG, Idaho Transportation Department
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species
of freshwater snail
with a gill and an operculum
, an aquatic
gastropod mollusk in the family Valvatidae
, the valve snails.
This species of snail is endemic to the United States
.
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
, Utah (the type locality
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
of the shell is obtusely elevated, and the apex
is depressed. The suture is well impressed. The aperture
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
of Utah
and in the Snake River
of southern Idaho
.
This snail is endemic to the Pliocene
of the Lake Idaho region.
The modern range of the snail extended as far downstream as Grandview
(rkm 783, rm
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
downstream to Burley
.
Recent surveys at The Nature Conservancy
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
The Utah valvata snail persists in a variety of aquatic habitats, including cold-water springs
, spring creeks and tributaries, the mainstem Snake River
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
, mud, or mud-sand substrate, among stream bed
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
(CaCO3) and silicon dioxide
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
(IPC) (1995-2002), IDFG, Idaho Transportation Department
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
, grazing along the mud surface ingesting diatoms or small plant debris. In habitats with boulders on mud, the snail has been observed grazing diatoms and other periphyton
(sessile organisms that live attached to rocky surfaces) and aquatic plants.
snail.
The Utah valvata snail is univoltine (produces one group of eggs per year) with a lifespan of about 1 year. Reproduction and spawning occur asynchronously between March and October, depending on habitat, with the majority of young spawned between August and October.
Emergence of a new cohort follows approximately 2 weeks after oviposition, and senescent snails (i.e., those approximately 374 days old) die shortly after reproduction.
The Utah valvata snail has been observed to produce egg masses which contained 3 to 12 developing snails. Egg masses are approximately 1.0 to 1.5 mm in diameter, and young snails are approximately 0.7 mm in size upon emergence.
Predators of the Utah valvata snail have not been documented; however, it is assumed that some predation by native and non-native species occurs.
on December 14, 1992.
On July 17, 2009, the Fish and Wildlife Service published a proposal in the Federal Register to remove the species from the list of endangered species stating that the Service now knows that the Utah valvata snail is not limited to areas of cold-water springs or spring outflows; rather, it persists in a variety of aquatic habitats, including cold-water springs, spring creeks and tributaries, the mainstream Snake River and associated tributary stream habitats, and reservoirs influenced by dam operations. The snail was delisted in 2010.
Valvata utahensis is listed as Data Deficient
species in the 2010 IUCN Red List of Threatened Species.
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 freshwater snail
Freshwater snail
A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....
with a gill and an operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
, an aquatic
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...
gastropod mollusk in the family Valvatidae
Valvatidae
Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks.- Taxonomy :...
, the valve snails.
This species of snail is endemic to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Taxonomy
This species was first described as Valvata sinceraValvata sincera
Valvata sincera, common name the mossy valvata or boreal turret snail, is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails.-Distribution:...
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
, Utah (the type locality
Biological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
Shell description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
Body whorl
Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
of the shell is obtusely elevated, and the apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
is depressed. The suture is well impressed. The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
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Fossil distribution
The Utah valvata snail, or at least its closely related ancestors, has been described as ranging widely across the western United States and Canada as far back as the Jurassic Period, 199.6 ± 0.6 to 145.5 ± 4 million years ago.Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
of Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
and in the Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
of southern Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
.
This snail is endemic to the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
of the Lake Idaho region.
Recent distribution
Grandview
- Canada :* Grandview, Manitoba* Grandview, Thunder Bay, Ontario, a neighbourhood in Thunder Bay, Ontario* Grandview, Prince Edward Island, a small community in eastern Prince Edward Island- United States :*Grand View, Idaho*Grandview, Illinois...
(rkm 783, rm
River mile
In the United States, a River mile is a measure of distance in miles along a river from its mouth. River mile numbers begin at zero and increase further upstream. The corresponding metric unit using kilometers is the River kilometer...
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
Minidoka Dam
The Minidoka Dam is an earthfill dam on the Snake River in south central Idaho. The dam, originally completed in 1906, is east of Rupert on county highway 400; it is 86 feet high and nearly a mile in length, with a wide overflow spillway section. The dam and power plant were listed on the...
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
American Falls Dam
The American Falls Dam is a concrete gravity-type dam located near the town of American Falls, Idaho, on river mile 714.7 of the Snake River. The dam and reservoir are a part of the Minidoka Project on the Snake River Plain and are used primarily for flood control, irrigation, and recreation...
downstream to Burley
Burley
- Place names :* Places in England:** Burley, Hampshire** Burley, Leeds** Burley, Rutland** Burley, Shropshire** Burley in Wharfedale, West Yorkshire, England* Places in the United States:** Burley, Idaho** Burley Manor, listed on the NRHP in Maryland...
.
Recent surveys at The Nature Conservancy
The Nature Conservancy
The Nature Conservancy is a US charitable environmental organization that works to preserve the plants, animals, and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive....
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
Habitat
The Utah valvata snail persists in a variety of aquatic habitats, including cold-water springsSpring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...
, spring creeks and tributaries, the mainstem Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
, mud, or mud-sand substrate, among stream bed
Stream bed
A stream bed is the channel bottom of a stream, river or creek; the physical confine of the normal water flow. The lateral confines or channel margins, during all but flood stage, are known as the stream banks or river banks. In fact, a flood occurs when a stream overflows its banks and flows onto...
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
(CaCO3) and silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
Idaho Department of Fish and Game
The Idaho Department of Fish and Game is the Idaho state department which is responsible for preserving and managing Idaho’s wildlife, including mammals, fish, birds, and invertebrates....
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
Idaho Power Company
Idaho Power Company is a regulated electrical power utility. Its business involves the purchase, sale, generation, transmission and distribution of electricity in eastern Oregon and southern Idaho. It is a subsidiary of IDACORP, Inc...
(IPC) (1995-2002), IDFG, Idaho Transportation Department
Idaho Transportation Department
The Idaho Transportation Department is the State of Idaho governmental organization responsible for the current transportation infrastructure. This includes ongoing operations and maintenance; as well as planning for future needs of the state and its citizens...
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species
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 freshwater snail
Freshwater snail
A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....
with a gill and an operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
, an aquatic
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...
gastropod mollusk in the family Valvatidae
Valvatidae
Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks.- Taxonomy :...
, the valve snails.
This species of snail is endemic to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Taxonomy
This species was first described as Valvata sinceraValvata sincera
Valvata sincera, common name the mossy valvata or boreal turret snail, is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails.-Distribution:...
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
, Utah (the type locality
Biological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
Shell description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
Body whorl
Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
of the shell is obtusely elevated, and the apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
is depressed. The suture is well impressed. The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
|
|
|
Fossil distribution
The Utah valvata snail, or at least its closely related ancestors, has been described as ranging widely across the western United States and Canada as far back as the Jurassic Period, 199.6 ± 0.6 to 145.5 ± 4 million years ago.Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
of Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
and in the Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
of southern Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
.
This snail is endemic to the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
of the Lake Idaho region.
Recent distribution
Grandview
- Canada :* Grandview, Manitoba* Grandview, Thunder Bay, Ontario, a neighbourhood in Thunder Bay, Ontario* Grandview, Prince Edward Island, a small community in eastern Prince Edward Island- United States :*Grand View, Idaho*Grandview, Illinois...
(rkm 783, rm
River mile
In the United States, a River mile is a measure of distance in miles along a river from its mouth. River mile numbers begin at zero and increase further upstream. The corresponding metric unit using kilometers is the River kilometer...
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
Minidoka Dam
The Minidoka Dam is an earthfill dam on the Snake River in south central Idaho. The dam, originally completed in 1906, is east of Rupert on county highway 400; it is 86 feet high and nearly a mile in length, with a wide overflow spillway section. The dam and power plant were listed on the...
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
American Falls Dam
The American Falls Dam is a concrete gravity-type dam located near the town of American Falls, Idaho, on river mile 714.7 of the Snake River. The dam and reservoir are a part of the Minidoka Project on the Snake River Plain and are used primarily for flood control, irrigation, and recreation...
downstream to Burley
Burley
- Place names :* Places in England:** Burley, Hampshire** Burley, Leeds** Burley, Rutland** Burley, Shropshire** Burley in Wharfedale, West Yorkshire, England* Places in the United States:** Burley, Idaho** Burley Manor, listed on the NRHP in Maryland...
.
Recent surveys at The Nature Conservancy
The Nature Conservancy
The Nature Conservancy is a US charitable environmental organization that works to preserve the plants, animals, and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive....
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
Habitat
The Utah valvata snail persists in a variety of aquatic habitats, including cold-water springs
Spring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...
, spring creeks and tributaries, the mainstem Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
, mud, or mud-sand substrate, among stream bed
Stream bed
A stream bed is the channel bottom of a stream, river or creek; the physical confine of the normal water flow. The lateral confines or channel margins, during all but flood stage, are known as the stream banks or river banks. In fact, a flood occurs when a stream overflows its banks and flows onto...
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
(CaCO3) and silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
Idaho Department of Fish and Game
The Idaho Department of Fish and Game is the Idaho state department which is responsible for preserving and managing Idaho’s wildlife, including mammals, fish, birds, and invertebrates....
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
Idaho Power Company
Idaho Power Company is a regulated electrical power utility. Its business involves the purchase, sale, generation, transmission and distribution of electricity in eastern Oregon and southern Idaho. It is a subsidiary of IDACORP, Inc...
(IPC) (1995-2002), IDFG, Idaho Transportation Department
Idaho Transportation Department
The Idaho Transportation Department is the State of Idaho governmental organization responsible for the current transportation infrastructure. This includes ongoing operations and maintenance; as well as planning for future needs of the state and its citizens...
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
The Utah roundmouth snail, also known as the Utah valvata or desert valvata, scientific name Valvata utahensis, is a species
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 freshwater snail
Freshwater snail
A freshwater snail is one kind of freshwater mollusc, the other kind being freshwater clams and mussels, i.e. freshwater bivalves. Specifically a freshwater snail is a gastropod that lives in a watery non-marine habitat. The majority of freshwater gastropods have a shell, with very few exceptions....
with a gill and an operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
, an aquatic
Aquatic animal
An aquatic animal is an animal, either vertebrate or invertebrate, which lives in water for most or all of its life. It may breathe air or extract its oxygen from that dissolved in water through specialised organs called gills, or directly through its skin. Natural environments and the animals that...
gastropod mollusk in the family Valvatidae
Valvatidae
Valvatidae, the valve snails, is a taxonomic family of very small freshwater snails with an operculum, aquatic gastropod mollusks.- Taxonomy :...
, the valve snails.
This species of snail is endemic to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
Taxonomy
This species was first described as Valvata sinceraValvata sincera
Valvata sincera, common name the mossy valvata or boreal turret snail, is a species of small freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Valvatidae, the valve snails.-Distribution:...
var. utahensis by Richard Ellsworth Call (1856-1917, U.S.A.) in 1884 from specimens collected at Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
, Utah (the type locality
Biological type
In biology, a type is one particular specimen of an organism to which the scientific name of that organism is formally attached...
).
R. E. Call elevated Valvata utahensis to species level in 1886 and this was confirmed also in revision of the genus by Bryant Walker (1856-1936, U.S.A.) in 1902.
There was established a subspecies Valvata utahensis horatii Baily & Baily, 1951 from pleistocene, but Taylor (1966) stated, that Valvata utahensis horatii should be a synonym for Valvata utahensis.
Shell description
The shellGastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...
of the Utah valvata snail is 4.5 mm high, and 4.5 mm width. The average size of adult Utah valvata snails is 4.32 mm.
The shell is turbinate in shape, thin, translucent and shining. It is a yellowish horn color at the apex, white or greenish white below the apex. The shell has four whorls
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...
which are convex, regularly increasing, minutely striate, the uppermost shouldered, with a single, well-marked carina which becomes obsolete on the body whorl
Body whorl
Body whorl is part of the morphology of a coiled gastropod mollusk.- In gastropods :In gastropods, the body whorl, or last whorl, is the most recently-formed and largest whorl of a spiral or helical shell, terminating in the aperture...
. Turbinate shell form and an incipient carina (keel-shaped ridge) on the dorsal surface of the shell distinguishes Valvata utahensis from the morphologically similar Valvata humeralis.
The spire
Spire (mollusc)
A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...
of the shell is obtusely elevated, and the apex
Apex (mollusc)
Apex is an anatomical term for the tip of the mollusc shell of a gastropod, scaphopod, or cephalopod mollusc.-Gastropods:The word "apex" is most often used to mean the tip of the spire of the shell of a gastropod...
is depressed. The suture is well impressed. The aperture
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....
of the shell is circular and slightly angled posteriorly. The lip of the aperture is simple, nearly continuous, and it is appressed to the body whorl.
The umbilicus is small and round; it is defined by a more or less obvious angle around the base of the shell.
The color of the operculum
Operculum (gastropod)
The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...
is light horn. The operculum is corneus, spirally multivolute, slightly produced posteriorly to conform to the shape of the aperture.
|
|
|
Fossil distribution
The Utah valvata snail, or at least its closely related ancestors, has been described as ranging widely across the western United States and Canada as far back as the Jurassic Period, 199.6 ± 0.6 to 145.5 ± 4 million years ago.Fossils of the Utah valvata snail are known from Utah to California. The Utah valvata snail was likely present in the ancestral Snake River as it flowed south from Idaho, through Nevada, and into northeastern California. The Snake River escaped to join the Columbia River Basin approximately 2 million years ago.
Historically, Valvata utahensis occurred in the Utah Lake
Utah Lake
Utah Lake is a freshwater lake in the U.S. state of Utah. On the western side of Utah Valley, the lake is overlooked by Mount Timpanogos and Mount Nebo. The lake's only river outlet, the Jordan River, is a tributary of the Great Salt Lake and is highly regulated with pumps. Evaporation accounts...
of Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
and in the Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
of southern Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
.
This snail is endemic to the Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
of the Lake Idaho region.
Recent distribution
Grandview
- Canada :* Grandview, Manitoba* Grandview, Thunder Bay, Ontario, a neighbourhood in Thunder Bay, Ontario* Grandview, Prince Edward Island, a small community in eastern Prince Edward Island- United States :*Grand View, Idaho*Grandview, Illinois...
(rkm 783, rm
River mile
In the United States, a River mile is a measure of distance in miles along a river from its mouth. River mile numbers begin at zero and increase further upstream. The corresponding metric unit using kilometers is the River kilometer...
487). However, recent mollusc surveys throughout Utah revealed no live snails, and the species is believed to be extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
there.
At present, this species occurs in a few springs and mainstem Snake River sites in the Hagerman Valley (rkm 932, rm 579). Additional locations include a few sites immediately upstream and downstream of the Minidoka Dam
Minidoka Dam
The Minidoka Dam is an earthfill dam on the Snake River in south central Idaho. The dam, originally completed in 1906, is east of Rupert on county highway 400; it is 86 feet high and nearly a mile in length, with a wide overflow spillway section. The dam and power plant were listed on the...
(rkm 1,086, rm 675), near the Eagle Rock dam site (rkm 1,142, rm 709) and below the American Falls Dam
American Falls Dam
The American Falls Dam is a concrete gravity-type dam located near the town of American Falls, Idaho, on river mile 714.7 of the Snake River. The dam and reservoir are a part of the Minidoka Project on the Snake River Plain and are used primarily for flood control, irrigation, and recreation...
downstream to Burley
Burley
- Place names :* Places in England:** Burley, Hampshire** Burley, Leeds** Burley, Rutland** Burley, Shropshire** Burley in Wharfedale, West Yorkshire, England* Places in the United States:** Burley, Idaho** Burley Manor, listed on the NRHP in Maryland...
.
Recent surveys at The Nature Conservancy
The Nature Conservancy
The Nature Conservancy is a US charitable environmental organization that works to preserve the plants, animals, and natural communities that represent the diversity of life on Earth by protecting the lands and waters they need to survive....
’s "Thousand Springs Preserve" revealed declines in numbers and range of the Utah valvata over a four-year period. In 1991, colonies of this snail persisted in only two areas at the Thousand Springs Preserve, with a population estimate for each colony at or below 6,000 individuals. The population density varied, but it averaged six individuals per meter2 (2.69 ft2).
For new localities see Federal Register, July 16, 2009.
Habitat
The Utah valvata snail persists in a variety of aquatic habitats, including cold-water springs
Spring (hydrosphere)
A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...
, spring creeks and tributaries, the mainstem Snake River
Snake River
The Snake is a major river of the greater Pacific Northwest in the United States. At long, it is the largest tributary of the Columbia River, the largest North American river that empties into the Pacific Ocean...
and associated tributary stream habitats, and reservoirs.
It was thought that the snail is specialized on well-oxygenated areas of limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
, mud, or mud-sand substrate, among stream bed
Stream bed
A stream bed is the channel bottom of a stream, river or creek; the physical confine of the normal water flow. The lateral confines or channel margins, during all but flood stage, are known as the stream banks or river banks. In fact, a flood occurs when a stream overflows its banks and flows onto...
s with submergent aquatic vegetation. I was thought that it is absent from pure gravel-boulder substrate. Chara, a rooted aquatic plant that concentrates both calcium carbonate
Calcium carbonate
Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks in all parts of the world, and is the main component of shells of marine organisms, snails, coal balls, pearls, and eggshells. Calcium carbonate is the active ingredient in agricultural lime,...
(CaCO3) and silicon dioxide
Silicon dioxide
The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...
(Si02), is a common associate of Valvata utahensis. However the species occurs on a variety of substrate types including both fine sediments and more coarse substrates in areas both with and without macrophytes.
The species has been collected at a wide range of depths, ranging from less than 1 m to depths greater than 14 m, and at temperatures between 4 and 24 °C (39.2 and 75.2 F).
Recent work conducted by the Idaho Department of Fish and Game
Idaho Department of Fish and Game
The Idaho Department of Fish and Game is the Idaho state department which is responsible for preserving and managing Idaho’s wildlife, including mammals, fish, birds, and invertebrates....
(IDFG) in the upper Snake River demonstrated that Utah valvata snail presence was positively correlated with water depth up to 5.5 m (up to 18.37 feet) and temperature up to 17.2 °C (up to 63 °F), and Utah valvata snail density was positively correlated with macrophyte (a water plant large enough to be observed with the unaided eye) coverage, water depth, and temperature.
Similarly, Hinson (2006) analyzed available data from several studies conducted by the USBR (2001-2004), Idaho Power Company
Idaho Power Company
Idaho Power Company is a regulated electrical power utility. Its business involves the purchase, sale, generation, transmission and distribution of electricity in eastern Oregon and southern Idaho. It is a subsidiary of IDACORP, Inc...
(IPC) (1995-2002), IDFG, Idaho Transportation Department
Idaho Transportation Department
The Idaho Transportation Department is the State of Idaho governmental organization responsible for the current transportation infrastructure. This includes ongoing operations and maintenance; as well as planning for future needs of the state and its citizens...
(2003-2004) and others, and demonstrated a positive relationship between Utah valvata snail presence and macrophytes, depth, and fine substrates. One study reported Utah valvata snails in organically enriched fine sediments with a heavy macrophyte community, downstream of an aquaculture facility (rm 588).
Survey data and information reported since the time of listing demonstrate that the Utah valvata snail is able to live in reservoirs, which were previously thought to be unsuitable for the species.
Feeding habits
Valvata utahensis is primarily a detritivoreDetritivore
Detritivores, also known as detritophages or detritus feeders or detritus eaters or saprophages, are heterotrophs that obtain nutrients by consuming detritus . By doing so, they contribute to decomposition and the nutrient cycles...
, grazing along the mud surface ingesting diatoms or small plant debris. In habitats with boulders on mud, the snail has been observed grazing diatoms and other periphyton
Periphyton
Periphyton are a complex mixture of algae, cyanobacteria, heterotrophic microbes, and detritus that are attached to submerged surfaces in most aquatic ecosystems. It serves as an important food source for invertebrates, tadpoles, and some fish. It can also absorb contaminants; removing them from...
(sessile organisms that live attached to rocky surfaces) and aquatic plants.
Life cycle
Utah roundmouth snail is a hermaphroditicHermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
snail.
The Utah valvata snail is univoltine (produces one group of eggs per year) with a lifespan of about 1 year. Reproduction and spawning occur asynchronously between March and October, depending on habitat, with the majority of young spawned between August and October.
Emergence of a new cohort follows approximately 2 weeks after oviposition, and senescent snails (i.e., those approximately 374 days old) die shortly after reproduction.
The Utah valvata snail has been observed to produce egg masses which contained 3 to 12 developing snails. Egg masses are approximately 1.0 to 1.5 mm in diameter, and young snails are approximately 0.7 mm in size upon emergence.
Interspecific relationships
The occurrence of trematode parasites in the Utah valvata has not been studied.Predators of the Utah valvata snail have not been documented; however, it is assumed that some predation by native and non-native species occurs.
Conservation
This species was listed as endangered on the United States Fish and Wildlife Service list of endangered speciesUnited States Fish and Wildlife Service list of endangered species
This list contains only the bird and mammal species described as endangered by the United States Fish and Wildlife Service. It contains species not only in the U.S. and its territories, but also species only found abroad. It does not contain fish, amphibians, reptiles, plants, or invertebrates,...
on December 14, 1992.
On July 17, 2009, the Fish and Wildlife Service published a proposal in the Federal Register to remove the species from the list of endangered species stating that the Service now knows that the Utah valvata snail is not limited to areas of cold-water springs or spring outflows; rather, it persists in a variety of aquatic habitats, including cold-water springs, spring creeks and tributaries, the mainstream Snake River and associated tributary stream habitats, and reservoirs influenced by dam operations. The snail was delisted in 2010.
Valvata utahensis is listed as Data Deficient
Data Deficient
Data Deficient is a category applied by the IUCN, other agencies, and individuals to a species when the available information is not sufficient for a proper assessment of conservation status to be made...
species in the 2010 IUCN Red List of Threatened Species.
Further reading
- Lysne S. & Koetsier P. (2008). "Comparison of Desert Valvata Snail Growth at Three Densities of the Invasive New Zealand Mudsnail". Western North American Naturalist 68(1): 103-106.
- Miller M. P., Weigel D. E. & Mock K. E. (2006). "Patterns of genetic structure in the endangered aquatic gastropod Valvata utahensis (Mollusca: Valvatidae) at small and large spatial scales". Freshwater Biology 51(12): 2362-2375. doi:10.1111/j.1365-2427.2006.01665.x.
- Taylor D. W. (1966). "Summary of North American Blancan nonmarine mollusks". MalacologiaMalacologiaMalacologia is a peer-reviewed scientific journal in the field of malacology, the study of mollusks. The journal publishes articles in the fields of molluscan systematics, ecology, population ecology, genetics, molecular genetics, evolution, and phylogenetics.The journal specializes in publishing...
4(1): 1-172. Figure 6 - the map.