Pokémon – A Venomoth / Butterfree Theory

Venomoth, Butterfree Theory - Pokemon
Written by:
Luke Ward
Est. reading time:
2 mins read

Today we give you not a fact, but a theory, about Venonat and Butterfree from Pokémon.

If you’re a fan of Pokémon, you have to check this out!

Caterpie was originally supposed to evolve into a Venomoth.

There are many similarities between Venonat and Butterfree – the similar colors, huge red eyes, antennas, their hands and even similar mouths look similar.

Also the appearance between Metapod and Venomoth are similar, with their same shaped head, black eyes and even the number of arms are the same as Caterpie.

Venonat - Butterfree Pokemon Theory

What does this all mean though?

Well for some reason Nintendo decided to swap Venomoth with Butterfree at the last moment.

The main theory about why they done this goes back to when the anime first started.

Ash’s second Pokémon was a Caterpie – as the creators had planned, however once it had reached its final evolution, it would not looks as cute and attractive as a big bug-eyed butterfly.

Therefore they decided to change the two around so that it would be easier for children to get attached to Caterpie’s final evolution.

Also Butterfree is classed as being white colored in the Pokédex, even though the main part of its body is purple.

Facts you may not have known.

Out of the first generation Bug Pokémon, Venomoth has the highest base Special Attack and ties with Scyther for the highest base HP.

Venomoth’s name is simply a combination of venom and moth.

Butterfree’s name is a combination of butterfly and free, which possibly refers to its ability to fly after being grounded for two evolutionary stages.

Catrpie was the first Pokémon to be seen evolving in the anime.

In Generation I, Venonat could not learn any damage dealing Poison moves at all even though it is a poison-type Pokémon.

In Pokémon did you know that the character Caterpie was originally supposed to evolve into Venomoth?

Leave A Comment


  1. Sam 8 May 2019

    Nah because the anime was made a year after the games and was made because the games were so popular in the first place

  2. Justin 12 August 2016

    Entomologist here. Venemoth is more likely than butterfree to be a butterfly. The shape of venomoth’s wings is clearly that of a swallowtail butterfly. This matches with caterpie’s osmeterium (orange horn), another unique feature of swallowtail butterflies. Butterfree’s wings appear transparent, which is common in moths but very rare in butterflies.

  3. Maggie 25 July 2016

    Another fun fact about venomoth: its venomous pronounced with a lisp.

  4. Guerillonist 12 September 2012


    Maybe was this the reason: Shortly before the release the programmers noticed, that a moth envolving from a caterpillar does not make sense. So they switched Venomoth and Butterfree ( maybe gave them new names ), but for a leck of time, they had no possibility to make new sprites for them. But we can only guess

    1. Ant Onymous 13 May 2013

      Moths develop from caterpillars in the real world, just like butterflies….

  5. pipi 4 July 2012

    Does it really make sense for a catapiller to evolve into a moth?

    1. br 6 November 2013


  6. DarkShadowDP 8 November 2011

    can venomoth learn fly

    1. Ray 28 May 2020

      That is actually a really good question, because I know there are a ton of pokemon that SHOULD be able to learn fly that cannot, like Charizard, and vise versa, like Dodrio (seriously, pokemon, he doesn’t even have wings!). I wanna say no, but I could be very wrong.

  7. Vhayes8886 19 June 2011

    actrually when pokemon green was being programmed they messed up and switched the sprites (graphics). at the time it was too soon to the release date to worry about it. it was easier to switch the colors … so they did.

    1. Krabbe Gurgel 16 March 2013

      Sure, sure. Your source is?

  8. Guest 11 May 2011

    Sorry but the original red and blue was before the anime so if your hypothesis is true, then it must have a different reason as to why they switched it.

    1. Maggie 25 July 2016

      Or, here’s a crazy thought: making a tv show takes a lot of time. A good few episodes would’ve been made before red and green launched in japan, and switching a few lines of code to change two evolutions takes a lot less time than redrawing several episodes.