Anophryoides haemophila (Ciliate Disease) of Lobsters


Category 2 (In Canada and of Regional Concern)

Common, generally accepted names of the organism or disease agent

Ciliate disease of lobsters, Bumper car disease.

Scientific name or taxonomic affiliation

Anophryoides (=Mugardia, =Paranophrys, =Anophrys) haemophila, a holotrich ciliate in the order Scuticociliatida, family Orchitophryidae.

Geographic distribution

Eastern United States and east coast of Canada.

Host species

Homarus americanus (closely related species infect crabs and cultured shrimp).

Impact on the host

Ciliate attaches to and destroys haemocytes and is lethal for lobsters. Believed to be an opportunistic parasite with naturally-occurring and experimentally induced disease being associated with cold (<5 ºC) water temperatures. Infection route not known but may be via lesions or breaks in membranes. May be a significant impediment to the economic viability of coldwater impoundments in eastern North America.

Diagnostic techniques

Gross Observations: Heavily infected lobsters show weakness and letharagy and the haemolymph may have a milky appearance with significantly reduced (or absent) clotting ability.

Smears: Examine hepatopancreas or haemolymph smears (that were fixed in methanol and stained with Giemsa's stain) for ciliates that are 35 by 22 µm in average total length and diameter.

Wet Mounts: Examine haemolymph for ciliates. Live ciliates (even at cold temperatures between 0 to 10 ºC) are active swimmers moving rapidly forward until colliding with an obstacle. They then reverse direction slightly, spin about on their vertical axis and swim away in a different direction.

Histology: Because A. haemophila is initally sequestered in lobster tissues for an extended period after infection, they are first detectable in histological sections of the hepatopancreas, gills, heart and muscle tissues. In advanced infections, the ciliate becomes systemic and can be detected via techniques indicated above. Tissue destruction may be visible.

Culture: Anophryoides haemophila can be propagated at 0 to 2 ºC in sterile artificial seawater supplemented with pieces of lobster muscle (0.1 g of muscle per 50 ml of seawater).

Immunological Assay: Monoclonal antibodies prepared against sonicated A. haemophila have been incorporated into immunoperoxidase and indirect fluorescent antibody staining protocols (Cawthorn 1997)

DNA Probes: Oligonucleotide probes, based on A. haemophila ssu-rDNA, that can discriminate between DNA of A. haemophila and other hymenostome ciliates were developed. Also, A. haemophila DNA was detected in at least a 1600-fold excess of total DNA from H. americanus using a polymerase chain reaction-based technique (Ragan et al. 1996).

Methods of control

No known methods of prevention. Because A. haemophila is killed in vitro by 1 hr exposures to formalin (50 mg/L) and low salinity (8.0 parts per thousand) that are tolerated by lobsters, such treatments may be effective in reducing ciliate numbers in the containes and on the surfaces of lobster held in impoundments (Speare et al. 1996)


Aiken, D.E., J.B. Sochasky and P.G. Wells. 1973. Ciliate infestation of the blood of the Lobster Homarus americanus. International Council for the Exploration of the Sea, Shellfish and Benthos Committee Report CM 1973/K: 46. 2p.

Cawthorn, R.J. 1997. Overview of "bumper car" disease - impact on the North American lobster fishery. International Journal for Parasitology 27: 167-172.

Cawthorn, R.J., D.H. Lynn, B. Despres, R. MacMillan, R. Maloney, M. Loughlin and R. Bayer. 1996. Description of Anophryoides haemophila n. sp. (Scuticociliatida: Orchitophryidae), a pathogen of American lobsters Homarus americanus. Diseases of Aquatic Organisms 24: 143-148.

Novotny, M.J., R.J. Cawthorn and B. Despres. 1996. In vitro effects of chemotherapeutants on the lobster parasite Anophryoides haemophila. Diseases of Aquatic Organisms 24: 233-237.

Ragan, M.A., R.J. Cawthorn, B. Despres, C.A. Murphy, R.K. Singh, M.B. Loughlin and R.C. Bayer. 1996. The lobster parasite Anophryoides haemophila (Scuticociliatida: Orchitophryidae): nuclear 18S rDNA sequence, phylogeny and detection using oligonucleotide primers. The Journal of Eukaryotic Microbiology 43: 341-346.

Sherburne, S.W. and L. Bean. 1991. Mortalities of impounded and feral marine lobsters, Homarus americanus H. Wilne-Edwards, 1837, caused by the protozoan ciliate Mugardia (formerly Anophrys-Paranophrys), with initial prevalence data from ten locations along the Maine coast and one offshore area. Journal of Shellfish Research 10(2): 315-326.

Speare, D.J., R.J. Cawthorn, B.S. Horney, R. MacMillan and A.L. MacKenzie. 1996. Effects of formalin, chloramine-T, and low salinity dip on the behavior and hemolymph biochemistry of the American lobster. Canadian Veterinary Journal 37: 729-734.

Citation Information

Bower, S.M. (1997): Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish: Anophryoides haemophila (Ciliate Disease) of Lobsters.

Date last revised: December 1997
Comments to Susan Bower

Date modified: