Acanthocephalan Larvae in Lobsters


Category 4 (Negligible Regulatory Significance in Canada)

Common, generally accepted names of the organism or disease agent

Acanthocephalan larvae in lobsters, cystacanth infection.

Scientific name or taxonomic affiliation

Polymorphus (=Corynosoma) (=Profilicollis) botulus.

Geographic distribution

Eastern Canada and adjacent coast of New England.

Host species

Homarus americanus, also reported from Carcinus maenas in Scotland.

Impact on the host

The life cycle of P. botulus normally occurs between sea ducks (eg., eiders and scoters) and crabs. Thus, infections in commercial-sized lobsters were probably acquired from crabs that form an important dietary item of lobsters. The lobster probably represents a dead end host for the parasite. Cystacanths usually occur in lobsters collected adjacent to the coast.

Diagnostic techniques

Squash Preparations: Cystacanths were embedded in or perforated the intestine wall and occasionally occurred in the haemocoel and hepatopancreas.

Methods of control

No known methods of prevention or control.


Brattey, J. and A. Campbell. 1986. A survey of parasites of the American lobster, Homarus americanus (Crustacea: Decapoda), from the Canadian Maritimes. Canadian Journal of Zoology 64: 1998-2003.

Uzmann, J.R. 1970. Use of parasites in identifying lobster stocks. The Journal of Parasitology 56: 349. (abstract).

Citation Information

Bower, S.M. (1996): Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish: Acanthocephalan Larvae in Lobsters.

Date last revised: September 1996
Comments to Susan Bower

Date modified: