Alien crayfish species

friendly Red swamp crayfish (<em>Procambarus clarkii</em>) form I male. The species has a propensity to migrate over land and can spread to new habitats with no connecting surface water. <em>Procambarus clarkii </em>– note that the species grows considerably larger at higher latitudes
Exuviae of <em>Orconectes immunis</em> <em>Orconectes immunis</em> male in its shelter
burrows of <em>O. immunis</em> in a backwater of the Rhine River <em>Orconectes immunis</em> form I male
<em>O. immunis</em> (left) and <em>O. limosus</em> (right) in burrows The invasives club: <em>Orconectes limosus</em>, <em>Corbicula fluminea</em>, and <em>Dikerogammarus villosus </em>
Marmorkrebs, <em>Procambarus fallax</em> f. <em>virginalis</em>. These animals are basically a natural clone army... <em>Orconectes juvenilis</em> male upon capture. The species was first recorded from the Dessoubre River, eastern France, in 2005.
<em>Orconectes juvenilis</em> female. The species is closely related to <em>O. rusticus</em>, one of the worst invasive aquatic species in North America. <em>Orconectes limosus</em> – an invasive paradox in that this species is a highly successful invader in Europe but at the same time threatened in its native range
<em>Orconectes limosus</em> female showing the high fecundity typical for this <em>r</em>-selected species. In the laboratory, a pleopodal fecundity of up to 680 eggs was recorded. Signal crayfish (<em>Pacifastacus leniusculus</em>) were the winners of a swedish casting for the best replacement of Nobe crayfish. Today, it is one of the worst invasive crayfish species in Europe
Signal crayfish are quite aggressive and displace native crayfish species <em>Orconectes virilis</em> is one of the New alien crayfish species in Europe. The species is a successful invader in the Netherlands and Great Britain. Virile crayfish are among the largest <em>Orconectes</em> species and have a considerable potential to cause ecological damage.
<em>Cherax destructor</em> is one of the two southern-hemisphere crayfish species currently present in Europe Spiny-cheek crayfish feature indeed spiny cheeks. The prominent hepatic spines represent a unique trait among the crayfish species to be found in Europe.
Narrow-clawed crayfish are the largest crayfish species to be found in Central European waters. The species is quite diverse in morphology and ecology and represents an as-yet unresolved species complex with at least two distinct evolutionary lineages. Unlike males, Narrow-clawed crayfish females lack the conspicuous elongated and slender chelae tips, after which the species is named.