Weird Creature of the Day: Red Triangle Slug
Thank you for the wonderfully positive response yesterday! Today we're checking out Triboniophorus graeffei!
Red triangle slugs are a common air-breathing slug found along the east coast of Australia. They are considered part of the Athoracophoridae family, also called the leaf-veined slug family. Measuring up to 15 cm/5.9 in, they are Austalia's largest native land slug!
Like most slugs, they love damp spaces such as forests, shrublands, gardens, and, on occasion, your bathroom. They primarily eat algae off of eucalyptus trees, and also sometimes mold, if they're visiting your home. You'll know if this guy has recently had lunch by the telltale circular marks their radula (mouth) leaves behind.
The iconic jaunty red triangle around their breathing pore reminds me of 80s/90s fashion and/or bowling alley carpet. And! It matches the red edge they have around their foot-- very fashion-forward. They don't develop this pattern until adulthood.
Some individuals have markings that are more red or orange, and their main body may be yellow, grey, white, pink, red, or even green. Research is still being done to determine if these variations merit classifying them into separate species.
While they may be considered common, red triangle slugs have one hell of a defense mechanism that sets them apart from other common slugs. While all slugs secrete a slippery mucus that helps them slide around, red triangle slugs can ALSO secrete a highly adhesive mucus that can pin predators down, sometimes for days at a time! Perhaps you will not find her common now!
Coincidentally, this slug lives in the same place that the fictional cartoon dog Bluey does (Brisbane).








