Socorro springsnail
Encyclopedia
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species
of minute freshwater snail
with a gill
and an operculum
, an aquatic
gastropod mollusk or micromollusk
in the family Hydrobiidae
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
in the State of New Mexico
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 whorls
. The protoconch
is usually eroded. The internal callus is reddish brown to amber, and the operculum
is pale. The height of the shell is 1.6–2.3 mm, and its aperture
is ovate.
The body, head, snout
and tentacles are dark gray to black in color. The tentacle
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
of this snail species was provided by Hershler in 1994.
The animal respires
by using a type of gill
known as a ctenidium
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
This species is endemic to Socorro County
in central New Mexico
in the southwestern United States
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
substrate
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
.
and other materials that occur in the organic film
which is found on the surface of plants and debris.
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
, if they include widespread drought
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
, which also covered another species, the Alamosa springsnail
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species
of minute freshwater snail
with a gill
and an operculum
, an aquatic
gastropod mollusk or micromollusk
in the family Hydrobiidae
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
in the State of New Mexico
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 whorls
. The protoconch
is usually eroded. The internal callus is reddish brown to amber, and the operculum
is pale. The height of the shell is 1.6–2.3 mm, and its aperture
is ovate.
The body, head, snout
and tentacles are dark gray to black in color. The tentacle
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
of this snail species was provided by Hershler in 1994.
The animal respires
by using a type of gill
known as a ctenidium
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
This species is endemic to Socorro County
in central New Mexico
in the southwestern United States
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
substrate
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
.
and other materials that occur in the organic film
which is found on the surface of plants and debris.
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
, if they include widespread drought
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
, which also covered another species, the Alamosa springsnail
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species
of minute freshwater snail
with a gill
and an operculum
, an aquatic
gastropod mollusk or micromollusk
in the family Hydrobiidae
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
in the State of New Mexico
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 whorls
. The protoconch
is usually eroded. The internal callus is reddish brown to amber, and the operculum
is pale. The height of the shell is 1.6–2.3 mm, and its aperture
is ovate.
The body, head, snout
and tentacles are dark gray to black in color. The tentacle
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
of this snail species was provided by Hershler in 1994.
The animal respires
by using a type of gill
known as a ctenidium
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
This species is endemic to Socorro County
in central New Mexico
in the southwestern United States
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
substrate
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
.
and other materials that occur in the organic film
which is found on the surface of plants and debris.
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
, if they include widespread drought
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
, which also covered another species, the Alamosa springsnail
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of minute freshwater snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
with a gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
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 or micromollusk
Micromollusk
A micromollusk is a descriptive term for a shelled mollusk which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine mollusks, although in addition, numerous species of land snails and freshwater mollusks also reach adult size at very small...
in the family Hydrobiidae
Hydrobiidae
Hydrobiidae, common name mud snails, is a large cosmopolitan taxonomic family of very small freshwater snails and brackish water snails that have an operculum, aquatic gastropod mollusks in the clade Littorinimorpha.- Distribution :...
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
in the State of New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
Taxonomy
The Socorro springsnail was originally described from warm springs in Socorro, New MexicoSocorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
Henry Augustus Pilsbry
Henry Augustus Pilsbry was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century...
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
John B. Burch
John Bayard Burch is an American zoologist, a biology professor at the University of Michigan, and is the Curator of Mollusks at the University of Michigan Museum of Zoology. His research interests are broad, and have encompassed not only the anatomy, systematics, and genetics of mollusks, but...
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. Admission is free and the museum is open 364 days a year....
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
Florida Museum of Natural History
The Florida Museum of Natural History is the State of Florida's official state-sponsored and chartered natural history museum. Its main facilities are located on the campus of the University of Florida in Gainesville, Florida....
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
Description
The Socorro springsnail has an elongate-ovate conical 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...
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 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...
. The protoconch
Protoconch
A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...
is usually eroded. The internal callus is reddish brown to amber, and 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 pale. The height of the shell is 1.6–2.3 mm, and its 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....
is ovate.
The body, head, snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
and tentacles are dark gray to black in color. The tentacle
Tentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...
of this snail species was provided by Hershler in 1994.
The animal respires
Respiration (physiology)
'In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...
by using a type of gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
known as a ctenidium
Ctenidium
Ctenidium may be:* Ctenidium , , a comb-like gill, part of the respiratory system of gastropods and bivalves* Ctenidium, , a row of peg-like spines in some insects...
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
Distribution
Socorro County, New Mexico
-2010:Whereas according to the 2010 U.S. Census Bureau:*75.1% White*1.1% Black*11.7% Native American*1.2% Asian*0.0% Native Hawaiian or Pacific Islander*2.8% Two or more races*8.1% Other races*48.5% Hispanic or Latino -2000:...
in central New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
in the southwestern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
Habitat
The Socorro springsnail is entirely aquatic, occurring in low-velocity (slow-moving) water near spring sources in a thermal habitat, i.e. near hot springs. More precisely, it is found in the uppermost layer of an organic muckMuck (soil)
Muck is a soil made up primarily of humus from drained swampland. It is known as black soil in The Fens of eastern England, where it was originally mainly fen and bog. It is used there, as in the United States, for growing specialty crops such as onions, carrots, celery, and potatoes...
substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
Pisidium casertanum
Pisidium casertanum, the pea cockle or pea clam, is a minute freshwater bivalve mollusc of the family Sphaeriidae.- Description :...
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
Socorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
Thermosphaeroma thermophilum
Thermosphaeroma thermophilum, commonly known as the Socorro isopod or Socorro sowbug, is a crustacean in the family Sphaeromatidae...
.
Feeding habits
This species is herbivorous. It feeds on algaeAlgae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
and other materials that occur in the organic film
Biofilm
A biofilm is an aggregate of microorganisms in which cells adhere to each other on a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substance...
which is found on the surface of plants and debris.
Life cycle
The females of the Socorro springsnail are oviparous, in other words, they lay eggs. They probably deposit eggs in spring and summer.Threats
The limited range and precise habitat demands of the Socorro springsnail makes this species vulnerable to habitat loss or alteration. Potential threats to the species include all activities that would significantly reduce either spring flow or availability of the food source that supports this springsnail species. Alterations to the watershedsDrainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
, if they include widespread drought
Drought
A drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
Conservation
The State of New Mexico listed the Socorro springsnail as endangered, group 2, on March 28, 1985 (Section 17—2—37 through 17—2—46 NMSA 1978). On October 30, 1991, the U.S. Fish and Wildlife Service also listed this species as endangered under the Endangered Species ActEndangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
Habitat conservation
Habitat conservation is a land management practice that seeks to conserve, protect and restore, habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range...
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
Conservation management system
A conservation management system is a procedure for maintaining a species or habitat in a particular state. It is a means whereby humankind secures wildlife in a favourable condition for contemplation, education or research, in perpetuity. It is an important topic in cultural ecology, where...
, which also covered another species, the Alamosa springsnail
Alamosa springsnail
Tryonia alamosae, common name the Alamosa springsnail, is a species of small freshwater snail, an aquatic prosobranch gastropod mollusk in the family Hydrobiidae....
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.
External links
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of minute freshwater snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
with a gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
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 or micromollusk
Micromollusk
A micromollusk is a descriptive term for a shelled mollusk which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine mollusks, although in addition, numerous species of land snails and freshwater mollusks also reach adult size at very small...
in the family Hydrobiidae
Hydrobiidae
Hydrobiidae, common name mud snails, is a large cosmopolitan taxonomic family of very small freshwater snails and brackish water snails that have an operculum, aquatic gastropod mollusks in the clade Littorinimorpha.- Distribution :...
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
in the State of New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
Taxonomy
The Socorro springsnail was originally described from warm springs in Socorro, New MexicoSocorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
Henry Augustus Pilsbry
Henry Augustus Pilsbry was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century...
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
John B. Burch
John Bayard Burch is an American zoologist, a biology professor at the University of Michigan, and is the Curator of Mollusks at the University of Michigan Museum of Zoology. His research interests are broad, and have encompassed not only the anatomy, systematics, and genetics of mollusks, but...
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. Admission is free and the museum is open 364 days a year....
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
Florida Museum of Natural History
The Florida Museum of Natural History is the State of Florida's official state-sponsored and chartered natural history museum. Its main facilities are located on the campus of the University of Florida in Gainesville, Florida....
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
Description
The Socorro springsnail has an elongate-ovate conical 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...
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 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...
. The protoconch
Protoconch
A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...
is usually eroded. The internal callus is reddish brown to amber, and 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 pale. The height of the shell is 1.6–2.3 mm, and its 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....
is ovate.
The body, head, snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
and tentacles are dark gray to black in color. The tentacle
Tentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...
of this snail species was provided by Hershler in 1994.
The animal respires
Respiration (physiology)
'In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...
by using a type of gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
known as a ctenidium
Ctenidium
Ctenidium may be:* Ctenidium , , a comb-like gill, part of the respiratory system of gastropods and bivalves* Ctenidium, , a row of peg-like spines in some insects...
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
Distribution
Socorro County, New Mexico
-2010:Whereas according to the 2010 U.S. Census Bureau:*75.1% White*1.1% Black*11.7% Native American*1.2% Asian*0.0% Native Hawaiian or Pacific Islander*2.8% Two or more races*8.1% Other races*48.5% Hispanic or Latino -2000:...
in central New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
in the southwestern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
Habitat
The Socorro springsnail is entirely aquatic, occurring in low-velocity (slow-moving) water near spring sources in a thermal habitat, i.e. near hot springs. More precisely, it is found in the uppermost layer of an organic muckMuck (soil)
Muck is a soil made up primarily of humus from drained swampland. It is known as black soil in The Fens of eastern England, where it was originally mainly fen and bog. It is used there, as in the United States, for growing specialty crops such as onions, carrots, celery, and potatoes...
substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
Pisidium casertanum
Pisidium casertanum, the pea cockle or pea clam, is a minute freshwater bivalve mollusc of the family Sphaeriidae.- Description :...
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
Socorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
Thermosphaeroma thermophilum
Thermosphaeroma thermophilum, commonly known as the Socorro isopod or Socorro sowbug, is a crustacean in the family Sphaeromatidae...
.
Feeding habits
This species is herbivorous. It feeds on algaeAlgae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
and other materials that occur in the organic film
Biofilm
A biofilm is an aggregate of microorganisms in which cells adhere to each other on a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substance...
which is found on the surface of plants and debris.
Life cycle
The females of the Socorro springsnail are oviparous, in other words, they lay eggs. They probably deposit eggs in spring and summer.Threats
The limited range and precise habitat demands of the Socorro springsnail makes this species vulnerable to habitat loss or alteration. Potential threats to the species include all activities that would significantly reduce either spring flow or availability of the food source that supports this springsnail species. Alterations to the watershedsDrainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
, if they include widespread drought
Drought
A drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
Conservation
The State of New Mexico listed the Socorro springsnail as endangered, group 2, on March 28, 1985 (Section 17—2—37 through 17—2—46 NMSA 1978). On October 30, 1991, the U.S. Fish and Wildlife Service also listed this species as endangered under the Endangered Species ActEndangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
Habitat conservation
Habitat conservation is a land management practice that seeks to conserve, protect and restore, habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range...
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
Conservation management system
A conservation management system is a procedure for maintaining a species or habitat in a particular state. It is a means whereby humankind secures wildlife in a favourable condition for contemplation, education or research, in perpetuity. It is an important topic in cultural ecology, where...
, which also covered another species, the Alamosa springsnail
Alamosa springsnail
Tryonia alamosae, common name the Alamosa springsnail, is a species of small freshwater snail, an aquatic prosobranch gastropod mollusk in the family Hydrobiidae....
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.
External links
The Socorro springsnail, scientific name Pyrgulopsis neomexicana, is an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of minute freshwater snail
Snail
Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...
with a gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
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 or micromollusk
Micromollusk
A micromollusk is a descriptive term for a shelled mollusk which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine mollusks, although in addition, numerous species of land snails and freshwater mollusks also reach adult size at very small...
in the family Hydrobiidae
Hydrobiidae
Hydrobiidae, common name mud snails, is a large cosmopolitan taxonomic family of very small freshwater snails and brackish water snails that have an operculum, aquatic gastropod mollusks in the clade Littorinimorpha.- Distribution :...
, the mud snails.
This tiny snail previously inhabited a small group of thermal springs
Hot spring
A hot spring is a spring that is produced by the emergence of geothermally heated groundwater from the Earth's crust. There are geothermal hot springs in many locations all over the crust of the earth.-Definitions:...
in the State of New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, USA. Its survival is seriously endangered because its habitat is both vulnerable and severely threatened. The current status of the population of this snail and its habitat area is unknown. The Socorro springsnail has been listed as endangered by the governments of the United States and the State of New Mexico.
Very little is known about this snail in general, because of its minute size, its very restricted range, and the fact that the places where it currently lives are on private property which allows no access.
Taxonomy
The Socorro springsnail was originally described from warm springs in Socorro, New MexicoSocorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
. The collector and date of the unique first sample are unknown. Specimens came from the collection of American mineralogist Charles Moore Wheatley (1822 Essex, England - 1882, Phoenixville, Pennsylvania, U.S.A.) and were likely collected in the 19th century. The species was formally described and named Amnicola neomexicana by American malacologist (mollusk expert) Henry Augustus Pilsbry
Henry Augustus Pilsbry
Henry Augustus Pilsbry was an American biologist, malacologist and carcinologist, among other areas of study. He was a dominant presence in many fields of invertebrate taxonomy for the better part of a century...
in 1916.
Pilsbry's original type description, the text where the species is officially named and described, reads as follows:
In 1982, American zoologist John B. Burch
John B. Burch
John Bayard Burch is an American zoologist, a biology professor at the University of Michigan, and is the Curator of Mollusks at the University of Michigan Museum of Zoology. His research interests are broad, and have encompassed not only the anatomy, systematics, and genetics of mollusks, but...
reclassified the Socorro springsnail as Fontelicella neomexicana. In 1987, two other American zoologists, Robert Hershler from the National Museum of Natural History
National Museum of Natural History
The National Museum of Natural History is a natural history museum administered by the Smithsonian Institution, located on the National Mall in Washington, D.C., United States. Admission is free and the museum is open 364 days a year....
and Fred Gilbert Thompson from the Florida State Museum (now the Florida Museum of Natural History
Florida Museum of Natural History
The Florida Museum of Natural History is the State of Florida's official state-sponsored and chartered natural history museum. Its main facilities are located on the campus of the University of Florida in Gainesville, Florida....
) assigned members of the genus Fontelicella, including F. neomexicana, to the genus Pyrgulopsis.
Description
The Socorro springsnail has an elongate-ovate conical 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...
that is light tan and short-spired, in other words the shell is low and rounded, without much of a pointed "tip" to it. The shell has 3.5–4.5 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...
. The protoconch
Protoconch
A protoconch is an embryonic or larval shell of some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod...
is usually eroded. The internal callus is reddish brown to amber, and 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 pale. The height of the shell is 1.6–2.3 mm, and its 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....
is ovate.
The body, head, snout
Snout
The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...
and tentacles are dark gray to black in color. The tentacle
Tentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s range from black or dark gray at the base, to pale gray at the tips. Female snails are larger than males. In the male, the penis has a long glandular strip on the terminal lobe, a long penial gland, and three shorter dorsal glandular strips. A detailed description of the reproductive system
Reproductive system of gastropods
The reproductive system of gastropods varies greatly from one group to another within this very large and diverse taxonomic class of animals...
of this snail species was provided by Hershler in 1994.
The animal respires
Respiration (physiology)
'In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...
by using a type of gill
Gill
A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
known as a ctenidium
Ctenidium
Ctenidium may be:* Ctenidium , , a comb-like gill, part of the respiratory system of gastropods and bivalves* Ctenidium, , a row of peg-like spines in some insects...
(a comb-like respiratory apparatus) which in this species has 20 tall and narrow ctenidial filaments.
In all of the species in the genus Pyrgulopsis, the radula
Radula
The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...
(a strong rasping feeding ribbon covered in microscopic teeth) is of taenioglossan type (seven teeth in each row, i.e. one middle, two laterals and 4 marginals.) The radula of Pyrgulopsis neomexicana was described in detail by Hershler (1994).
Distribution
Socorro County, New Mexico
-2010:Whereas according to the 2010 U.S. Census Bureau:*75.1% White*1.1% Black*11.7% Native American*1.2% Asian*0.0% Native Hawaiian or Pacific Islander*2.8% Two or more races*8.1% Other races*48.5% Hispanic or Latino -2000:...
in central New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
in the southwestern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. The original specimen of the Socorro springsnail reportedly came from a thermal spring near Socorro, New Mexico.
It is now extinct at the type locality, but the date and cause of the extinction are uncertain. The species has been reported from other springs in Socorro County (Landye 1981), although there is disagreement on whether the species historically occurred there. Currently, the Socorro springsnail is known from only one spring: the Torreon Spring in Socorro County, New Mexico, where it was located in 1979.
Habitat
The Socorro springsnail is entirely aquatic, occurring in low-velocity (slow-moving) water near spring sources in a thermal habitat, i.e. near hot springs. More precisely, it is found in the uppermost layer of an organic muckMuck (soil)
Muck is a soil made up primarily of humus from drained swampland. It is known as black soil in The Fens of eastern England, where it was originally mainly fen and bog. It is used there, as in the United States, for growing specialty crops such as onions, carrots, celery, and potatoes...
substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
or surface.
The principal spring source where the Socorro springsnail is currently found has been impounded (artificially enclosed, blocked off or dammed), and this has reduced the flowing-water habitat to a very small pool. Only one tiny spring source remains, and this has a small improved pool (less than 1 m² in area), with a water temperature of 17 °C. The species is abundant on rootlets in this pool, but is not found in the ditches and ponds radiating from the spring into irrigation structures. Other mollusks found in the vicinity include Physa mexicana, Lymnaea modicella, and Pisidium casertanum
Pisidium casertanum
Pisidium casertanum, the pea cockle or pea clam, is a minute freshwater bivalve mollusc of the family Sphaeriidae.- Description :...
. In 1981, the colony of Socorro springsnails was found to occupy not only the source, but also the outflow tributary about 2.5 m (8 ft) long to an irrigation ditch. No snails were found in the irrigation flow itself however. In 1991, the total population of the Socorro springsnail in the spring outflow was estimated at 5,000 individuals.
The snail had formerly occurred throughout the thermal springs west of the city of Socorro
Socorro, New Mexico
Socorro is a city in Socorro County in the U.S. state of New Mexico. It stands in the Rio Grande Valley at an elevation of . The population was 9,051 at the 2010 census...
, living in the same habitats as the Socorro isopod Thermosphaeroma thermophilum
Thermosphaeroma thermophilum
Thermosphaeroma thermophilum, commonly known as the Socorro isopod or Socorro sowbug, is a crustacean in the family Sphaeromatidae...
.
Feeding habits
This species is herbivorous. It feeds on algaeAlgae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
and other materials that occur in the organic film
Biofilm
A biofilm is an aggregate of microorganisms in which cells adhere to each other on a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substance...
which is found on the surface of plants and debris.
Life cycle
The females of the Socorro springsnail are oviparous, in other words, they lay eggs. They probably deposit eggs in spring and summer.Threats
The limited range and precise habitat demands of the Socorro springsnail makes this species vulnerable to habitat loss or alteration. Potential threats to the species include all activities that would significantly reduce either spring flow or availability of the food source that supports this springsnail species. Alterations to the watershedsDrainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
, springs, or associated runs could cause a reduction in water flow, a change in water temperature or water quality, or could modify the habitat or food source. This could have a devastating impact on the existing populations of the snail.
This snail species has extremely limited dispersal
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...
capabilities, which means it has little or no ability to find, and disperse to, other suitable habitats, or to move out of a habitat where the conditions have changed such that it is no longer suitable. Consequently, these snails are unable to avoid contaminants or other unfavorable changes to their habitat.
The population of the Socorro springsnail is thought to be limited to a single pool which is less than 1 m² in area, and an outflow ditch about 2.5 m (8 ft) in length. Several of the springs that formerly contained the Socorro springsnail have been impounded, and this has eliminated the precise habitat that is critical for the species’ survival.
Perhaps the greatest threat facing this species is the potential loss of water flow. Excessive pumping from the aquifer that supplies water to the springs could destroy both the springs themselves and the species along with them. Potential pollution of the spring could negatively impact this species and perhaps could also cause its extinction. The effects of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
, if they include widespread drought
Drought
A drought is an extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation. It can have a substantial impact on the ecosystem and agriculture of the affected region...
, decreased spring discharge, or a change in water chemistry, are a newly-recognized threat that could eliminate the species.
Conservation
The State of New Mexico listed the Socorro springsnail as endangered, group 2, on March 28, 1985 (Section 17—2—37 through 17—2—46 NMSA 1978). On October 30, 1991, the U.S. Fish and Wildlife Service also listed this species as endangered under the Endangered Species ActEndangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
of 1973. Because of the extremely limited distribution, the recovery strategy for this species has its foundation in the maintenance of their habitat. While it is possible that additional populations might be established in other thermal springs, this possibility is contingent upon finding springs within the species’ presumed historic range that have the physical and biologic attributes, including terrestrial habitat components, that the springsnail requires to survive, and which do not support their own endemic fauna.
The locality is on private land and access to the spring has been denied since 1995. Because of this, the recent population numbers are unknown, the status of the habitat is unknown, and the magnitude of current threats is also unknown. Lack of cooperation by the private land owner and impacts caused by their actions were not specifically identified as a threat. However the U.S. Fish and Wildlife Service recommendations for further actions suggested that efforts should continue in an attempt to gain access to the spring. If and when access is granted, it was recommended that life history studies should be carried out, monitor population numbers should be monitored, the attributes of suitable habitat should be determined (qualities like the exact nature of the preferred substrate, the water temperature limits, pH, hardness, alkalinity etc.) and that long-term monitoring of discharge and temperature should be set up. If on the other hand, access continues to be denied, the recommendation was to attempt to set up a one-time visit to the spring in order to collect individuals for a captive refugium population.
A decision was made by the U.S. Fish and Wildlife Service not to implement the part of the Endangered Species Act
Endangered Species Act
The Endangered Species Act of 1973 is one of the dozens of United States environmental laws passed in the 1970s. Signed into law by President Richard Nixon on December 28, 1973, it was designed to protect critically imperiled species from extinction as a "consequence of economic growth and...
which allows the authorities to acquire land as necessary if it is "critical habitat" for the conservation of a listed species, because it was felt in this situation that making the land public would actually expose the remaining population to an even greater risk of extinction from threats such as vandalism and collection by unauthorized parties. A habitat management plan
Habitat conservation
Habitat conservation is a land management practice that seeks to conserve, protect and restore, habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range...
had not yet been written for the species as of 2008, as was directed by the 1994 recovery plan
Conservation management system
A conservation management system is a procedure for maintaining a species or habitat in a particular state. It is a means whereby humankind secures wildlife in a favourable condition for contemplation, education or research, in perpetuity. It is an important topic in cultural ecology, where...
, which also covered another species, the Alamosa springsnail
Alamosa springsnail
Tryonia alamosae, common name the Alamosa springsnail, is a species of small freshwater snail, an aquatic prosobranch gastropod mollusk in the family Hydrobiidae....
. The 1994 recovery plan is out of date and needs to be revised and updated. It was recommended that a separate plan should be created.