Tag Archives: starfish

Mareanie and Toxapex: The Crown-of-Thorns Pokémon (Pokémon Eating Pokémon Part 1)


The sea in many ways is a curious contradiction, as it is simultaneously the womb of life and home to a fierce array of predators. It is both the source nourishment and great cruelty. Hidden underneath its beautiful foaming blue sheets are the most crafty and devious creatures ever to have been seen by men. Swarms of jellyfish dragging their forest of stinging needles through the ocean currents, packs of prehistoric sharks so fine-tuned for predation that they have gone relatively unchanged since their dinosaurs, as is a common theme with nature’s apex predators.

The Pokémon oceans are no safer. In place of jellyfish are hordes of Tentacruel who cause fish to scatter whenever to congregate (1). Sharpedo zip through the water upwards of 75 mph, slicing through hulls of ship and snaring any unfortunate prey in their razor teeth, appropriately earning the title of The Bully of the Sea (2).

But lurking just off the coast of Melemele Island in the Alola region is a particularly devious critter. The waters of Alola are host to a problematic set of predators commonly known as Mareanie and its evolved form, Toxapex. Classified as the Brutal Star Pokémon, Mareanie has an infamous reputation for feasting on Corsola.

It’s found crawling on beaches and seafloors. The coral that grows on Corsola’s head is as good as a five-star banquet to this Pokémon. (Pokémon Moon)

But this predation is not limited to mere words in a Pokédex. The Seventh Generation of Pokémon Games introduced a new mechanic known as SOS battles, in which, a wild Pokémon will call upon an additional “ally” Pokémon to aid it in battle if it’s health drops below 50%.


However, in the case of Corsola, on rare occasion a Mareanie will appear when it calls. But instead of attacking the trainer’s Pokémon, Mareanie will instead attack the very Corsola that called it to battle, in many cases even knocking out the poor Coral Pokémon. Furthermore, to the frustration of many gamers, this is the only way Mareanie can be obtained in the game.

But it terms of sheer brutality, its evolved form, Toxapex, takes the cake:

Toxapex crawls along the ocean floor on its 12 legs. It leaves a trail of Corsola bits scattered in its wake(Pokémon Sun)

Those attacked by Toxapex’s poison will suffer intense pain for three days and three nights. Post recovery, there will be some aftereffects(Pokémon Moon)


Toxapex, the Brutal Star Pokémon

While at first glance, these entries may seem like the typical Pokédex hyperbole, with a few word tweaks these could easily describe the real-life Acanthaster planci—the Crown-of-Thorns starfish.

Most common in the oceans of Australia, though distributed throughout Indo-Pacific waters, the Crown-of-Thorns starfish crawls along the sea floor in search of coral polyps which it primarily feeds on. Like its Alolan counterparts, the Crown-of Thorns starfish is a Poison-Type per say, as it is armed with an arsenal of toxins known as saponins. While we can only speculate on the aftereffects of Toxapex’s poisonous sting, in human, the crown-of-thorns sting can lead to a plethora of symptoms, including swelling around the site of entry, followed by a sharp sting that can last for hours, nausea, and bleeding (9). Indeed, there will be some aftereffects.

Just as Mareanie and Toxapex prey on Corsola, the Crown-of-Thorns starfish preys on coral, which, unlike the Pokémon Corsola, are sessile organisms. Considering how slow most starfish move, this is only to the Crown-of-Thorn’s advantage. Possessing as many as 21 tentacles (3), the starfish attaches itself to living coral colonies where it begins its feeding process. First, the starfish forces its stomach out of its mouth and onto the surface of the coral. It then releases digestive enzymes to break down the coral tissue. As the starfish retracts its stomach, it draws in the broken-down tissues, leaving a scar of white coral skeleton, often referred to as a “feeding scar” (4) .


“Feeding scar” on Australian coral reef from crown-of-thorns starfish.

While not as brutal as Toxapex’s treatment of Corsola, the feeding habits of Acanthaster planci can have deleterious effects on coral colonies and coral reef ecosystems as a whole. Once a feeding scar has formed, surrounding algae will infest the wound, resulting in a crusty skeleton appearance (5). In most cases, the corals—while not in the best aesthetic state—continue to live, though with their vibrancy diminished. However, in this weakened state, some species of coral will crumble due to agitation from storms and other sources of rough waters. Moreover, in addition to invasions by filamentous algae, other organisms such as sponges and “soft corals” will move in on the feeding scars. Gradually, this cascades into an environmental shift in which surfaces where hard coral polyps would take hold are occupied by the invaders. This, in effect, deprives many fish and marine herbivores of their habitat and food sources (6).

Now consider the following PokéDex from Pokémon Sapphire Version:

“Clusters of Corsola congregate in warm seas where they serve as ideal hiding places for smaller Pokémon.” – Pokémon Sapphire Version

Perhaps a similar effect is found in Alola as a result of Mareanie/Toxapex’s predation of Corsola. This would explain Corsola’s rare encounter rate, as well as other Pokémon supposedly endemic to Alola.

Additionally, starfish populations are on the rise. Currently, the exact cause for this spike in population is unknown. Some proposed hypotheses include the depletion of natural predators due to overfishing, rising sea temperatures enhancing the development of larvae, or that simply these observed outbreaks are no more than an aggregate of starfish having previously consumed all adjacent coral colonies and thus cluster together in a single area. Regardless of the cause, the impact of these creatures remains severe, as a study of the Great Barrier Reef revealed that over a 27-year-long period, in a survey of 214 coral reefs, the reef suffered a 50.7% loss of initial coral cover (7). The damage was attributed to three main causes—tropical storms, coral bleaching, and the crown-of-thorns starfish. The starfish alone were responsible for 42% of the total coral loss.

However, there is hope. Recently, researchers have discovered a means of controlling these seemingly invincible organisms. A single, careful, injection of household vinegar into the tentacle of a crown-of-thorns starfish can render the starfish lifeless within 48 hours (8). While the death of any creature—even one that is quite a nuisance—is unfortunate, it is the hope of conservationist and environmental agencies alike that this new treatment will spare the last of the world’s reefs from the wrath of the Crown-O-Thorns.

Perhaps a similar method could be employed on the Mareanie of Alola.

Of course, you would have to find one first.

A suggestion. If you stumble across a Mareanie, don’t faint it, either with Pokémon or your mother’s vinegar.


Accurate Pokédex Entry (Mareanie): In Alola, much of the Corsola loss in recent years can be attributed to a spike in Mareanie populations. However, scientists have found that injections of household vinegar might be used to control their growing population.

Accurate Pokédex Entry (Toxapex): No one knows for sure why its numbers are on the rise. One hypothesis is that overfishing has depleted the oceans of Alola of Toxapex’s natural enemies, allowing the Brutal Star Pokémon to proliferate unchecked, leaving Corsola everywhere scarred and crumbling.


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Works Cited

  1. Game Freak. Pokémon Moon.Nintendo, 2016. Nintendo 3DS.
  2. Game Freak. PokémonSun.Nintendo, 2016. Nintendo 3DS.
  3. Caso, M.J. (1974). “External morphology of Acanthasterplanci (Linnaeus)”. Journal of the Marine Biological Associataion of India16 (1): 83–93.
  4. Current Biology
  5. Belk, D (1975). “An observation of algal colonization on Acropora asperakilled by Acanthaster planci‘.”. Hydrobiologia46 (1): 29–32. doi:10.1007/bf00038724.
  6. Wilson, S K; Dolman, A M; Cheal, A J; Emslie, MJ Pratchett; et al. (2009). “Maintenance of fish diversity on disturbed coral reefs”. Coral reefs28(1): 3–14. doi:10.1007/s00338-008-0431-2.
  7. De’ath, G. et al. 2012. The 27–year decline of coral cover on the Great Barrier Reef and its causes. PNAS109:17995-17999.
  8. Boström-Einarsson, L. & Rivera-Posada, J. Coral Reefs (2016) 35: 223. doi:10.1007/s00338-015-1351-6
  9. Birkelandand Lucas (1990). Acanthaster planci: Major Management Problem of Coral Reefs. CRC Press. pp. 131–132. ISBN 0-8493-6599-6.