 Harlequin Ladybird (Harmonia axyridis) Dorset, 2006 |
 Tube Web Spider (Segestria florentina) Kew, 2009 |
 Signal Crayfish (Pacifastacus leniusculus) Herts, 2010 |
British Isles Exotic and Introduced Miscellaneous Creatures
Platyhelminthes
New Zealand Flatworm- Arthurdendyus triangulatusFirst discovered in Northern Ireland in the 1960's it is now present in West Scotland and central England, it is a pest decimating earthworm populations.
Arthropoda
Stick Insects
Prickly - Acanthoxyla geisovii from New Zealand.
Smooth - Clitarchus hookerifrom New Zealand. Unarmed - Acanthoxyla inermis from New Zealand. European - Bacillus rossius from the Mediterranean Acanthoxyla prasina from New Zealand. Another species Clonopsis gallica from New Zealand has been introduced on to Jersey. The five species, Acanthoxyla prasina, unarmed, prickly, Mediterranean and smooth are found in small colonies in Cornwall. All derived from pets the mild climate has allowed them to persist. A few colonies also exist in other parts of the country. Tresco Gardens is a hotspot, they are widespread on the Scilly isles and SW Cornwall.
LadybirdsHarlequin Ladybird - Harmonia axyridisA highly invasive species first recorded in East Anglia in 2004, it has quickly spread and is present in most on England south of Lancashire / Yorkshire and has not yet reached the South West. As its name suggests is comes in 24 differnt colour forms From mostly black to mostly orange to mostly yellow with lots of forms inbetween. Originally introduced to central europe.
CrayfishSignal Crayfish - Pacifastacus leniusculusOne of five species introduced to the UK, the Signal crayfish is the most distinctive and most disruptive. Originally introduced for food it quickly escaped and has out competed the native species and carrys a fungus which kills the native species. Found on most waterways. Other species are not as widespread or disruptive
Noble crayfish - Astacus astacus
Yellow Tailed Scorpion- Euscorpius flavicaudisThey arrived by hitching a ride on ships and were found at several docks, the Sheerness colony has been in existant since the 1960's. The last surviving colony is at Sheerness, which despite my best efforts I have been unable to gain access to.
Chinese Mittern Crab- Eriocheir sinensisFirst recorded in the River Thames in the 1930s, possibly arrived in ships ballast water, originally from the far east they have no competitors in the UK so have recently dispersed and numbers have risen. in ships from the Far East. Native to China and Korea, the species took a long time to become established, possibly because of the river's polluted state. Since the early 1990s, however, numbers have mushroomed. The crab, which can travel over dry land, has now spread to many other English rivers hot spots are the Thames, Humber and Tyne and the east coast.
Large Checkered skipper- Heteropterus morpheusIntroduced into Jersey in 1940's but died out in in the 1990's
Spiders
Tube Web Spider - Segestria florentina Well established for about 100 years in the south and london. It has a nasty bite but is not venomous but is very aggressive.
False Widow Spider - Steatoda paykulliana A major colony exists in Plymouth and they are spreading. This species has a nasty and venomous bite and is aggressive.
Skeleton Shrimp- Caprella muticaA relatively large, shrimp native to north-east Asia. This species is now widespread in Scottish coastal waters, occurring in high numbers on artificial structures such as mooring ropes and nets at fisheries, and on pontoons and boat hulls in marinas.
Molluscs
Pacific Oyster- Crassostrea gigasIntroduced initially in Cornwall, Essex and Wales for food production. It has been widely farmed in England, Scotland, Wales and Northern Ireland. 'Escapees' have established populations in many regions.
Slipper Limpet- Crepidula fornicataIn Britain, it is present on the east coast south of Hull, the length of the south coast and northwards along the west coast to Cardigan.
New Zealand Mud Snail- Potamopyrgus antipodarum
Cliveden Snail- Papillifera papillarisAccidently imported from Italy on a marble balustrade in 1896 into Cliveden Park, Bucks only discovered in 2008.
Chordates
Leathery Sea Squirt- Styela clavaA large, leathery stalked sea squirt that has spread extensively since its first European occurrence in Plymouth in the early 1950s, and now occurs in natural habitats as well as docks, harbours and marinas. It is extensively encrusted by other species.
Fish
Rainbow Trout- Salmo gairdneriA game fish released from the late 1800's and still commonly released it is common in rivers and lakes throughout the UK.
American Brook Charr- Salvelinus fontinalisAn American fish found mainly in the NW, Wales and Scotland. A late 1800s introduction for game fishing.
Common Carp- Cyprinus carpioCommonly introduced to lakes in the south, conditions further north are unsuitable for breeding and they have not done well there.
Goldfish- Carassius auratusCommonly kept in captivity and have been widely released.
Bitterling- Rhodeus amarusEscaped from captivity in the north of England where it is scarce but self sustaining.
Orfe- Leuciscus idusCommonly kept in captivity and have been widely released.
Wells- Silurus glanisA large catfish first introduced into Woburn abbey in the late 1800's but has spread into lots of lakes and river systems in the south. It is originally from mainland europe.
Guppy- Poecilia reticulataA tropical species that has become established in several areas where the water is warmed by factories and power stations. Other commonly kept tropical species can also be found at these sites but are much less common.
Zander- Stizostedion luciopercaIntroduced by anglers to rivers and lakes in Southern England but is rapidly spreading. It is a vicious preadator and harmfull to small native species.
Topmouth Gudgen- Pseudorasbora parvaSimilar to the Gudgeon but with the mouth pointing upwards, it breeds prolifically and carries a parasite potentially dangerous to native species.
Pumpkinseed- Lepomis gibbosusA North American native, present in the South East and East Anglia, it is not spreading and its introduction method has not been confirmed.
Sunbleak- Leucaspius delineatusA recent introduction in the 1980's it is currently restricted to Southern England but is spreading.
|
 Prickly Stick Insect (Acanthoxyla geisovii) Cornwall, 2006 |
 Unarmed Stick Insect (Acanthoxyla inermis) Cornwall, 2007 |
 Smooth Stick Insect (Clitarchus hookeri) Cornwall, 2007 |
 False Widow Spider (Steatoda nobilis) Cornwall, 2009 |
 Cliveden Snail (Papillifera papillari) Bucks, 2009 |
 Signal Crayfish (Pacifastacus leniusculus) Herts, 2010 |
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