Episode 261 – Reef Stonefish: Point Taken

“…and today we’re talking about a stone at the bottom of the sea. Definitely don’t be on that later.”

It’s no surprise that the most venomous fish in the world is found in none other than the land down under. Hidden among the rocks and coral in Australia and the surrounding islands, the reef stonefish never backs down from a fight. Instead, it attacks with a vitriolic and very venomous vengeance. Its venom is so powerful, it’s worked its way into the folklore and rituals of the natives. But affecting the heart, mind, and soles of your feet is how the stonefish gets by here in Life, Death, and Taxonomy.

Description of the Reef Stonefish

  • Stonefish look something like a stone. They are short and squat with a bulldog expression and eyes beset on the top of their heads.
  • Stonefish can be striking with mottled yellow, orange, and red areas.
  • They also appear in brown and rust colors. 
  • They are scaleless but bumpy like coral. 
  • Stonefish have large and broad pectoral fins that extend outward.

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words Measure Up into ldtaxonomy at gmail dot com. We don’t have a new Measure Up intro!

Length

  • As long as 40 cm (16 in)
  • How many stonefish go into a sarissa?
  • Hint: A sarissa is a pike that was first introduced by Philip II of Macedon in the 300 BC. It was an important introduction to the phalanx formation used in Macedonia.
  • 15 stonefish. The sarissa was around 20 feet (6 meters).

Depth

  • 40 meters (131 feet)
  • Around 136 stonefish living depths go into the max depth of this ocean. What is the ocean?
  • Hint: This is the shallowest ocean on earth.
  • The Arctic ocean is 17,881 feet (5,450 meters) deep.

Fast Facts about the Reef Stonefish

Range

  • The stonefish lives in waters north of the Tropic of Capricorn. 
  • They enjoy shallow coastal waters in the Pacific and Indian Oceans, especially around coral reefs.
  • They are also found in the Red Sea, Mediterranean, and Suez Canal.

Diet

  • They eat small fish, shrimp and other crustaceans and pretty much anything that will fit in their mouths.
  • They are ambush predators and use camouflage to hide and wait for something to come by.
  • Their coloration and bumpy skin makes them look like a piece of coral or a rock in the sand.
  • When prey arrives, they can swallow them whole in 0.015 seconds (a human blink is (0.3 seconds.)

Major Fact: Point Taken

  • The stonerfish isn’t pushing the kind stuff to your kids though, they’re deadly and it’s high times we took note of it.
  • It actually takes the cake as the most venomous fish in the world. And potentially the most dangerous due to its habits.
  • Rather than swim away when threatened, the stonefish stays put and juts out up to 14 needle-sharp spikes attached to specialized glands filled with the deadliest toxin known to fish-kind called verrucotoxin.
    • These spikes are so sharp, they can even get you through the sole of a boot!
  • The toxin is a mix of enzymes and proteins and has an LD50 (the amount needed to kill 50% of a population of mice) as low as 38 ug/kg or micrograms per kilogram. A microgram is about the size of a grain of table salt.
    • As a reference, king cobra venom has an LD50 of about 282
    • But the batrachotoxin in Poison Dart frogs is most likely the worst one produced by animals at an LD50 of 2 micrograms per kilogram. 
  • Getting a subscription to Verrucotoxin gets you the following benefits:
    • Intense localized pain
    • Paralysis
    • Tissue destruction
    • Shock
    • Death
  • Fortunately, stings are relatively rare and all have been treated. In fact, there have been no recorded deaths due to the stonefish in Australia since Europeans arrived back in the 18th century. 
    • Now we even have an antitoxin to mitigate it even more
    • Researchers believe that native islanders and aborigines have died due to encounters with the stonefish though.
  • Actually, there is still a lot of research going on about the reef stonefish’s venom since they still aren’t sure exactly what the mechanism of action is. Another related species, the estuary stonefish, has a mechanism similar to a black widow’s venom.

Ending: So find a good hiding spot, cozy up on the seafloor, and if someone tries to step on you, give their foot the business like the stonefish here in LDT.