First bioluminescent terrestrial mollusc

The first (and currently the only) species of terrestrial mollusc known to be bioluminescent is Quantula (=Dyakia) striata, a tropical species of air-breathing gastropod land snail. Its eggs, juveniles, and most adults emit flashes of greenish light, with a wavelength of approximately 505 nanometres. Although bioluminescence was first recorded from this species in 1942, the substance responsible for it has still not been identified. This species is native to Cambodia, Malaysia, Singapore, Indonesia's Rhio Archipelago, the Philippines and Fiji.

In adult specimens of this snail, bioluminescence is most intense when moving, only half as much when feeding, and not at all when inactive. It originates from an organ called the "organ of Haneda", which is contained in the adult snail's head-foot region, and the flashes of light produced by it are thought to be involved in communication.