Bad case of crabs.

[Matthew X]

http://www.gov.sg/moh/mohiss/poison/pictor.html
Lophozozymus pictor (Thunder Crab)
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  It is a confirmed toxic species. It could be found inhabiting the coral 
reef beds in the southern islands off Singapore. An adult crab weighs about 
100 grams and 10 cm in width. It is usually brightly coloured and has 
mosaic patterns on its shell and as such is also know as the mosaic crab. 
Locally this is commonly called "Thunder Crab"; the Australians call it the 
"Red and White Reef Crab".
Several cases of human fatality in association with its consumption have 
been documented. The crab is highly toxic and to date there is no known 
antidote against such poisoning. Seek immediate medical treatment in any 
suspected case of poisoning.
Distribution: Singapore, Philippines, Indonesia and Australia.
Domoic Acid (ASP) in Shellfish
What is domoic acid?
Domoic acid is a naturally occurring toxin produced by microscopic algae, 
specifically the diatom Pseudo-nitzschia pungens.  Shellfish and crab 
ingest this algae, where the toxin concentrates.  Significant amounts of 
domoic acid can cause Amnesic Shellfish Poisoning (ASP) in humans.  ASP is 
transmitted by eating contaminated molluscan shellfish and crab.
http://www.doh.wa.gov/ehp/sf/Pubs/DomoicAcid.htm