Blue Ring Octopus: This golf ball size Octopus can inject a deadly neurotoxin and stop your heart in minutes. There is not know antidote and survival requires constant heart compression and assisted breathing until the toxin is out of the body...about 24 hours. Super pretty though.
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The diminutive blue-ringed octopus (Hapalochlaena lunulata) looks like a sweet, possibly even fantastical creature. Often measuring less than 20 centimeters long and covered with dozens of bright blue rings, it spends most of its time hiding out in shells or rocks near the beach. But don’t be fooled—this little cephalopod is trouble. One small nip from its beak can inject enough powerful neurotoxin to kill an adult human in minutes.