Lagenidium spp. (Fungus Disease) of Crabs


Category 4 (Negligible Regulatory Significance in Canada)

Common, generally accepted names of the organism or disease agent

Lagenidium or fungus disease of Dungeness crabs.

Scientific name or taxonomic affiliation

Lagenidium callinectes, Lagenidium sp.

Geographic distribution

Oregon, California, Atlantic and Gulf coasts of U.S.; probably ubiquitous.

Host species

Cancer magister egg and larvae, Callinectes sapidus eggs. Other marine crustaceans such as lobsters, shrimp and prawns can also be infected.

Impact on the host

Infects eggs and larvae on the periphery of egg masses on female crabs. Fungus may smother the eggs if the egg membrane is too hardened for it to penetrate. Infected eggs either deteriorate or cannot hatch successfully. Infected larvae have a fuzzy appearance, gradually cease swimming, become progressively opaque.

Diagnostic techniques

Gross Observations: Extramatrical hyphae with characteristic discharge vesicles and endobiotic hyphae in the transparent larvae are discernible with a dissecting microscope.

Microscopy: Specific diagnosis requires microscopic examination of hyphae and sporangia.

Methods of control

Prompt sterilization and proper disposal of of infected larvae and culture water, with complete sterilization of the rearing system is necessary before another culture effort can be initiated.


Armstrong, D.A. and W.S. Fisher. 1988. Fungus (Lagenidium) disease of Dungeness crabs. In: C.J. Sindermann and D.V. Lightner (eds.). Disease Diagnosis and Control in North American Marine Aquaculture. Developments in Aquaculture and Fisheries Science 17. Elsevier, Amsterdam, p. 215-219.

Messick, G.A. and C.J. Sindermann. 1992. Synopsis of principal diseases of the blue crab, Callinectes sapidus. NOAA Technical Memorandum NMFS-F/NEC-88. 24 p.

Sparks, A.K. 1985. Synopsis of Invertebrate Pathology Exclusive of Insects. Elsevier Science Publishing Co., Amsterdam. p. 230.

Citation Information

Bower, S.M., McGladdery, S.E., Price, I.M. (1994): Synopsis of Infectious Diseases and Parasites of Commercially Exploited Shellfish: Lagenidium spp. (Fungus Disease) of Crabs.

Date last revised: Fall 1994
Comments to Susan Bower

Date modified: