Linderiella occidentalis
Encyclopedia
Linderiella occidentalis (the California fairy shrimp or California Linderella) is a species
of fairy shrimp
native to California
. It is a small (about 1 cm long) crustacean in the family Chirocephalidae
family. It has a delicate elongate body, large stalked compound eyes, no carapace
, and eleven pairs of swimming legs
. It glides gracefully upside down, swimming by beating its legs in a complex, wavelike movement that passes from front to back. Like other fairy shrimp, L. occidentalis feeds on algae
, bacteria
, protozoa
, rotifer
s and detritus
.
Most fairy shrimp found in California belong to the family Branchinectidae
. These include the threatened vernal pool fairy shrimp, which is often found in the same pools. California fairy shrimp are smaller than Branchinecta
and have distinctive red eyes.
s and lakes. However, they can survive in clear to turbid water with pH
of 6.1–8.5, and they have been found in very small pools. They are tolerant of water temperatures from 5–29 °C (41–84.2 F), making them the most heat tolerant fairy shrimp in California.
Female fairy shrimp carry their eggs in a ventral brood sac. The eggs are either dropped to the pool bottom or remain in the brood sac until the mother dies and sinks. When the pool dries out, so do the eggs. They remain in the dry pool bed until rains and other environmental stimuli hatch them.
Resting fairy shrimp eggs are known as cyst
s. They are capable of withstanding heat, cold and prolonged desiccation
. When the pools refill, some, but not all, of the cysts may hatch. The cyst bank in the soil may contain cysts from several years of breeding.
Average time to maturity is about forty-five days. Thirty-one seems to be the minimum time required, which is the longest minimum for any Central Valley fairy shrimp. Adults have been collected from late December to early May.
When the United States Fish and Wildlife Service
listed the vernal pool fairy shrimp, vernal pool tadpole shrimp, conservancy fairy shrimp and longhorn fairy shrimp, they stated that surveys conducted in 1993 and other information that had become available to the Service indicated that the range extends from Shasta County
south to Fresno County
and across the valley to the Coast and Transverse Ranges
from Willits
in Mendocino County
south to near Sulfur Mountain in Ventura County
.
In addition to direct habitat loss, California fairy shrimp populations have declined because of a variety of activities that render existing vernal pools unsuitable for the species. Alteration of vernal pool hydrology
, in particular, can dramatically degrade vernal pool habitats. Vernal pool hydrology can be altered by a variety of activities, including the construction of roads, trails, ditches, or canals that can block the flow of water into, or drain water away from the vernal pools and vernal pool complexes.
Populations have also declined as a result of water contamination
. Vernal pool crustaceans are highly sensitive to the water chemistry of their habitats. Contamination of vernal pools may injure or kill them. Toxic chemicals, such as petroleum
products, pesticide
s, herbicide
s, fertilizer
s and soap
may wash into vernal pools during development of adjacent areas.
In addition to altered hydrology and contamination, California fairy shrimp habitats have declined as a result of a variety of other incompatible land uses including off-road vehicle
use, dumping, invasion of non-native species
, vandalism
, erosion
and sedimentation
.
It was proposed for listing along with the vernal pool fairy shrimp, vernal pool tadpole shrimp, conservancy fairy shrimp
and longhorn fairy shrimp. However the proposal was withdrawn when the other four species were listed. The Federal Register
notice stated "The Service has considered the additional information and has determined that the California linderiella is not likely to become either endangered or threatened throughout all or a significant portion of its range in the foreseeable future, and it does not qualify for listing under the Act.
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 fairy shrimp
Fairy shrimp
Anostraca is one of the four orders of crustaceans in the class Branchiopoda; its members are also known as fairy shrimp. They are usually long . Most species have 20 body segments, bearing 11 pairs of leaf-like phyllopodia , and the body lacks a carapace...
native to California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
. It is a small (about 1 cm long) crustacean in the family Chirocephalidae
Chirocephalidae
Chirocephalidae is a family of fairy shrimp, characterised by a reduced or vestigial maxilla, more than two setae on the fifth endite, divided pre-epipodites and widely separated seminal vesicles. It consists of the following eight genera, including the genera formerly placed in the families...
family. It has a delicate elongate body, large stalked compound eyes, no carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
, and eleven pairs of swimming legs
Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...
. It glides gracefully upside down, swimming by beating its legs in a complex, wavelike movement that passes from front to back. Like other fairy shrimp, L. occidentalis feeds on algae
Algae
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...
, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
, protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
, rotifer
Rotifer
The rotifers make up a phylum of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John Harris in 1696, and other forms were described by Anton van Leeuwenhoek in 1703...
s and detritus
Detritus
Detritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
.
Most fairy shrimp found in California belong to the family Branchinectidae
Branchinectidae
Branchinectidae is a family in the order Anostraca , containing two genera – Branchinecta and Archaebranchinecta. The majority of the species are in the genus Branchinecta, with only Archaebranchinecta pollicifera and the fossil Archaebranchinecta barstowensis in the second genus....
. These include the threatened vernal pool fairy shrimp, which is often found in the same pools. California fairy shrimp are smaller than Branchinecta
Branchinecta
Branchinecta is a genus of crustacean in family Branchinectidae. It includes around 50 species, found on all continents except Africa and Australia...
and have distinctive red eyes.
Life cycle
California fairy shrimp tend to live in large, fairly clear vernal poolVernal pool
Vernal pools, also called vernal ponds or ephemeral pools, are temporary pools of water. They are usually devoid of fish, and thus allow the safe development of natal amphibian and insect species...
s and lakes. However, they can survive in clear to turbid water with pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
of 6.1–8.5, and they have been found in very small pools. They are tolerant of water temperatures from 5–29 °C (41–84.2 F), making them the most heat tolerant fairy shrimp in California.
Female fairy shrimp carry their eggs in a ventral brood sac. The eggs are either dropped to the pool bottom or remain in the brood sac until the mother dies and sinks. When the pool dries out, so do the eggs. They remain in the dry pool bed until rains and other environmental stimuli hatch them.
Resting fairy shrimp eggs are known as cyst
Cyst
A cyst is a closed sac, having a distinct membrane and division on the nearby tissue. It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, a cyst could go away on its own or may have to be removed through surgery.- Locations :* Acne...
s. They are capable of withstanding heat, cold and prolonged desiccation
Desiccation
Desiccation is the state of extreme dryness, or the process of extreme drying. A desiccant is a hygroscopic substance that induces or sustains such a state in its local vicinity in a moderately sealed container.-Science:...
. When the pools refill, some, but not all, of the cysts may hatch. The cyst bank in the soil may contain cysts from several years of breeding.
Average time to maturity is about forty-five days. Thirty-one seems to be the minimum time required, which is the longest minimum for any Central Valley fairy shrimp. Adults have been collected from late December to early May.
Distribution
The California fairy shrimp is the most common fairy shrimp in the Central Valley. It has been documented on most land forms, geologic formations and soil types supporting vernal pools in California, at altitudes as high as 1150 metres (3,773 ft) above sea level.When the United States Fish and Wildlife Service
United States Fish and Wildlife Service
The United States Fish and Wildlife Service is a federal government agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats...
listed the vernal pool fairy shrimp, vernal pool tadpole shrimp, conservancy fairy shrimp and longhorn fairy shrimp, they stated that surveys conducted in 1993 and other information that had become available to the Service indicated that the range extends from Shasta County
Shasta County, California
Shasta County is a county located in the northern portion of the U.S. state of California. The county occupies the northern reaches of the Sacramento Valley, with portions extending into the southern reaches of the Cascade Range. As of the 2010 census, the population was 177,223, up from 163,256...
south to Fresno County
Fresno County, California
Fresno County is a county located in the Central Valley of the U.S. state of California, south of Stockton and north of Bakersfield. As of the 2010 census, it is the tenth most populous county in California with a population of 930,450, and the sixth largest in size with an area of . The county...
and across the valley to the Coast and Transverse Ranges
Transverse Ranges
The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region that runs along the Pacific coast from Alaska to Mexico in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie between...
from Willits
Willits, California
Willits is a city in Mendocino County, California, United States. Willits is located north-northwest of Ukiah, at an elevation of 1391 feet . The population was 4,888 at the 2010 census, down from 5,073 at the 2000 census. Willits is at the center of Mendocino County and its redwood forests...
in Mendocino County
Mendocino County, California
Mendocino County is a county located on the north coast of the U.S. state of California, north of the greater San Francisco Bay Area and west of the Central Valley. As of the 2010 census, the population was 87,841, up from 86,265 at the 2000 census...
south to near Sulfur Mountain in Ventura County
Ventura County, California
Ventura County is a county in the southern part of the U.S. state of California. It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...
.
Conservation
As with all vernal pool species that occur in the Central Valley, suitable habitat for the California fairy shrimp has declined dramatically over the past century. Continued conversion of grassland-vernal pool ecosystems to urban or agricultural uses is the largest threat to survival of the California fairy shrimp.In addition to direct habitat loss, California fairy shrimp populations have declined because of a variety of activities that render existing vernal pools unsuitable for the species. Alteration of vernal pool hydrology
Hydrology
Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...
, in particular, can dramatically degrade vernal pool habitats. Vernal pool hydrology can be altered by a variety of activities, including the construction of roads, trails, ditches, or canals that can block the flow of water into, or drain water away from the vernal pools and vernal pool complexes.
Populations have also declined as a result of water contamination
Contamination
Contamination is the presence of a minor and unwanted constituent in material, physical body, natural environment, at a workplace, etc.-Specifics:"Contamination" also has more specific meanings in science:...
. Vernal pool crustaceans are highly sensitive to the water chemistry of their habitats. Contamination of vernal pools may injure or kill them. Toxic chemicals, such as petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
products, pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
s, herbicide
Herbicide
Herbicides, also commonly known as weedkillers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic "imitations" of plant...
s, fertilizer
Fertilizer
Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
s and soap
Soap
In chemistry, soap is a salt of a fatty acid.IUPAC. "" Compendium of Chemical Terminology, 2nd ed. . Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford . XML on-line corrected version: created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN...
may wash into vernal pools during development of adjacent areas.
In addition to altered hydrology and contamination, California fairy shrimp habitats have declined as a result of a variety of other incompatible land uses including off-road vehicle
Off-road vehicle
An off-road vehicle is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks...
use, dumping, invasion of non-native species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
, vandalism
Vandalism
Vandalism is the behaviour attributed originally to the Vandals, by the Romans, in respect of culture: ruthless destruction or spoiling of anything beautiful or venerable...
, erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
and sedimentation
Sedimentation
Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained, and come to rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them: these forces can be due to gravity, centrifugal acceleration...
.
It was proposed for listing along with the vernal pool fairy shrimp, vernal pool tadpole shrimp, conservancy fairy shrimp
Conservancy fairy shrimp
The conservancy fairy shrimp, Branchinecta conservatio, is a small crustacean in the family Branchinectidae. It ranges in size from about to long. Fairy shrimp are aquatic species in the order Anostraca. They have delicate elongate bodies, large stalked compound eyes, no carapaces, and eleven...
and longhorn fairy shrimp. However the proposal was withdrawn when the other four species were listed. The Federal Register
Federal Register
The Federal Register , abbreviated FR, or sometimes Fed. Reg.) is the official journal of the federal government of the United States that contains most routine publications and public notices of government agencies...
notice stated "The Service has considered the additional information and has determined that the California linderiella is not likely to become either endangered or threatened throughout all or a significant portion of its range in the foreseeable future, and it does not qualify for listing under the Act.
Further reading
- California Dept. of Fish & Game, California Vernal Pool Assessment, Preliminary Report
- Eriksen, C. H., and D. Belk. 1999. Fairy shrimps of California's puddles, pools, and playas, Mad River Press, Eureka, CA.
- Holland, R. F. 1978. The geographic and edaphic distribution of vernal pools in the Great Central Valley, California. California Native Plant Society, Special Publication 4: 1–12.
- Holland, R. F., and S. Jain. 1988. Vernal pools. Pages 515–533 In: M. E. Barbour and J. Major, eds. Terrestrial vegetation of California, new expanded edition. California Native Plant Society, Special Publication Number 9, Sacramento, CA.
- U.S. Fish & Wildlife Service. 1994. Endangered and Threatened Wildlife and Plants; Withdrawal of the Proposal To Determine a Crustacean, the California Linderiella, an Endangered Species. Portland, Oregon.
- U.S. Fish & Wildlife Service. 1994. Endangered and Threatened Wildlife and Plants; Determination of Endangered Status and Withdrawal of Proposal to Give Endangered Status. Portland, Oregon.