There are no prizes for guessing where banana slugs (Ariolimax) get their common name from.
There are five species of banana slug, with most sporting an olive-green or yellow hue – although some are tan, brown or white, too.
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One of these species is the Pacific banana slug, which holds the record for the world’s second-largest species of terrestrial slug, measuring up to 25cm (9.8 inches).
But their appearance isn’t the only bizarre thing about this creature.
Banana slugs release their vivid yellow slime, which is laden with pheromones, to attract other slugs so it can mate.
All terrestrial slugs are hermaphrodites, meaning that each individual has male and female reproductive organs. However, self-fertilisation isn’t the preferred option for these animals as this risks inbreeding.
Once another slug appears, their mating dance involves circling around each other, sometimes lunging and nipping.
And in certain species of banana slugs, it’s been discovered that this dance ends in a type of ‘battle’ to eat the other’s penis. This is called apophallation, and can take around 45 minutes.
This is because after slugs have mated once, there’s more benefit to being a sperm-giver than a sperm-receiver, with the slugs battling it out to continue being the giver.
Most species are found exclusively in California, US, although some are found in other northwestern states and in Canada.
In fact, it’s so synonymous with the Golden State that the banana slug is the mascot of the University of California, Santa Cruz. And in September 2024, the banana slug was made the official state slug of California.
Top image: a banana slug on the vegetation of the forest floor. Credit: GomezDavid/Getty Images
