Ammothea hilgendorfi
Date of introduction and origin
Ammothea hilgendorfi was first observed in 1978 in
Southampton Water (Bamber 1985). This species is thought to have
been introduced from Japan. It originates in the tropical and
temperate North Pacific littoral zone of south-east Asia.
Method of introduction
It is transported on ships' hulls.
Reasons for success
Unknown.
Rate of spread and methods involved
Rate of spread is minimal without assistance from man (R.N.
Bamber pers. comm.).
Distribution
Currently it is known in Britain only from Southampton Water
(Bamber 1988). Elsewhere in Europe it has been found in a lagoon in
Venice.
Factors likely to influence spread and distribution
There is no dispersive phase in the species' life cycle which
means dispersal is very slow.
Effects on the environment
None.
Effects on commercial interests
Unknown.
Control methods used and effectiveness
None.
Beneficial effects
None known.
Comments
This is a species of no ecological or commercial significance.
Introduction to the lagoon in Venice is also presumed to have been
on a ship's hull.
Chocolate brown markings on the trunk and legs (as indicated
in the illustration) are a useful aid to identification.
References
Bamber, R.N. 1985. The itinerant sea spider Ammothea
hilgendorfi (Böhm) in British waters. Proceedings of
Hampshire Field Club & Archaeological Society,
41: 269-270.
Bamber, R.N. 1988. Confirmation of a new record. Porcupine
Newsletter, 4: 37.
Acknowledgements (contributions from questionnaire)
Dr R.N. Bamber, Aquatic Research Laboratories Ltd,
Southampton.