by Veronika Meduna
New Zealand is known for its extraordinary flora and fauna, which includes many species that are found nowhere else. One of our lesser known endemic animals is a tiny glowing limpet that lives only in stony streams throughout the North Island.
These luminescent limpets belong to the genus Latia, and they are the world’s only freshwater species capable of producing a brightly glowing slime. The limpets release the slime only when they are disturbed, and University of Auckland microbiologist and bioluminescence enthusiast Siouxsie Wiles thinks they use it mostly as a defense mechanism to startle or distract predators. She says it is also possible that some of the glowing slime sticks to the predator and makes it more at risk of being eaten itself.
Latia limpets are related to land snails and have evolved a limpet-like shell shape to cope with flowing waters. They are abundant in gently flowing stony-bottom streams in most parts of the North Island, where they graze on algae that grow on rock surfaces, and they are most common in streams with good water quality, which makes them a useful environmental indicator species.