Orconectes immunis
Encyclopedia
Orconectes immunis, the calico crayfish or papershell crayfish, is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

n freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...

 crayfish
Crayfish
Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...

 which has also been introduced to Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, where it lives along the Upper Rhine
Upper Rhine
The Upper Rhine is the section of the Rhine in the Upper Rhine Plain between Basel, Switzerland and Bingen, Germany. The river is marked by Rhine-kilometers 170 to 529 ....

. It lives in slow-flowing bodies of water, and can survive by burrowing if they dry out.

Description

Orconectes immunis is similar to a number of other species of crayfish in the genus Orconectes
Orconectes
Orconectes is a genus of freshwater crayfish, native to the eastern United States. It includes the rusty crayfish, an invasive species in North America, and Orconectes limosus, an invasive species in Europe.-Taxonomy:...

. While the colouration of the claws is distinctive, it can be difficult to use that to identify a specimen without reference specimens for comparison. O. immunis can be distinguished from O. virilis
Orconectes virilis
Orconectes virilis is a species of crayfish known as the virile crayfish or the northern crayfish.-Ecology:Orconectes virilis can be found under stones in lakes, streams and wetlands, where they hide from predators, such as fish. They are identified by the brown of rust-red carapace and large...

by the presence of a notch near the base of the dactylus (finger) of the claw, which is not found in O. virilis.

North America

Orconectes immunis naturally occurs across a wide area of eastern North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, from Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

 and Connecticut
Connecticut
Connecticut is a state in the New England region of the northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, and the state of New York to the west and the south .Connecticut is named for the Connecticut River, the major U.S. river that approximately...

 in the east to Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

 and Wyoming
Wyoming
Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 in the west, and from Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

 in the south to Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 in the north. In Canada, it has been recorded from Manitoba
Manitoba
Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...

, Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

 and Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

, although the populations in Quebec may be the result of introductions by angler
Angler
Angler may refer to:* A fisherman who uses the fishing technique of angling*Angler * The angler, Lophius piscatorius, a monkfish* More generally, any anglerfish in the order Lophiiformes* Angler , a Marvel Comics supervillain...

s from New York
New York
New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

; the Canadian populations are centred in southern Ontario. It is believed to have been introduced to a number of states in New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...

, including Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...

, Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...

, New Hampshire
New Hampshire
New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...

, Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...

 and Vermont
Vermont
Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England...

.

Europe

Orconectes immunis has been popular in the aquarium
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

 trade in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, and is kept as a pet both in aquaria and garden pond
Garden pond
A garden pond is a water feature constructed in a garden or designed landscape, normally for aesthetic purposes and/or to provide wildlife habitat.-Habitat:...

s. The first recorded escape was a single individual in a small canal in the Rhine valley of Baden-Württemberg
Baden-Württemberg
Baden-Württemberg is one of the 16 states of Germany. Baden-Württemberg is in the southwestern part of the country to the east of the Upper Rhine, and is the third largest in both area and population of Germany's sixteen states, with an area of and 10.7 million inhabitants...

 in 1997. Later, a breeding population was discovered, and this has now spread at least as far downstream as Karlsruhe
Karlsruhe
The City of Karlsruhe is a city in the southwest of Germany, in the state of Baden-Württemberg, located near the French-German border.Karlsruhe was founded in 1715 as Karlsruhe Palace, when Germany was a series of principalities and city states...

 (45 km or 28 mi downstream) and possibly as far as Speyer
Speyer
Speyer is a city of Rhineland-Palatinate, Germany with approximately 50,000 inhabitants. Located beside the river Rhine, Speyer is 25 km south of Ludwigshafen and Mannheim. Founded by the Romans, it is one of Germany's oldest cities...

 (35 km or 21.7 mi downstream from Karlsruhe). It has since been recorded from other locations in Europe, including the German state
States of Germany
Germany is made up of sixteen which are partly sovereign constituent states of the Federal Republic of Germany. Land literally translates as "country", and constitutionally speaking, they are constituent countries...

 of Rhineland-Palatinate
Rhineland-Palatinate
Rhineland-Palatinate is one of the 16 states of the Federal Republic of Germany. It has an area of and about four million inhabitants. The capital is Mainz. English speakers also commonly refer to the state by its German name, Rheinland-Pfalz ....

, as well as in France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

. It appears to be outcompeting another invasive 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....

, Orconectes limosus
Orconectes limosus
Orconectes limosus is a species of crayfish in the family Cambaridae. It is native to the east coast of North America, from Maine to the lower James River, Virginia, but has also been introduced to Europe. It is unusual in that it lives in silty streams, rather than the clear water usually...

, which has been present in the area for five decades.

Ecology

O. immunis is only found in slow-flowing bodies of water, such as stream
Stream
A stream is a body of water with a current, confined within a bed and stream banks. Depending on its locale or certain characteristics, a stream may be referred to as a branch, brook, beck, burn, creek, "crick", gill , kill, lick, rill, river, syke, bayou, rivulet, streamage, wash, run or...

s, pond
Pond
A pond is a body of standing water, either natural or man-made, that is usually smaller than a lake. A wide variety of man-made bodies of water are classified as ponds, including water gardens, water features and koi ponds; all designed for aesthetic ornamentation as landscape or architectural...

s, marsh
Marsh
In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

es and roadside ditches, in contrast to O. virilis
Orconectes virilis
Orconectes virilis is a species of crayfish known as the virile crayfish or the northern crayfish.-Ecology:Orconectes virilis can be found under stones in lakes, streams and wetlands, where they hide from predators, such as fish. They are identified by the brown of rust-red carapace and large...

which also lives in rivers with moderate flow. It can survive in areas with large fluctuations in the amount of available water, by burrowing into the ground when the surface waters recede.

Naming

O. immunis was first described by Hermann August Hagen
Hermann August Hagen
Hermann August Hagen was a German entomologist who specialised in Neuroptera and Odonata. In 1845 he began to collaborate with Edmond de Sélys Longchamps .-Biography:...

 in 1870, in his Monograph of the North American Astacidae, under the name Cambarus immunis. The original specimens came from Lawn Ridge, Marshall County
Marshall County, Illinois
The median income for a household in the county was $41,576, and the median income for a family was $48,061. Males had a median income of $35,765 versus $21,452 for females. The per capita income for the county was $19,065...

, Illinois
Illinois
Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

.

Common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...

s for the species include calico crayfish and papershell crayfish.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK