Tanyenn is a luminescent algae that grows in the Sea of Songs. It is a very useful and versatile plant to the Maerum and Alatien. Apart from its use as a convenient light source, it attracts small fish which can then be caught for food - while larger, predatory fish like the Snapjaw tend to avoid the light that Tanyenn emits. There is a suggestion that a lack of Tanyenn in the diet of the Alatien may be responsible for their weakening wings. The Maerum have a particular, very unusual use for it; if a human (or presumably any other sentient 'landwalker') ingests some of it with a specific type of pearl and some of his/her own blood, that individual is then be able to comprehend the language of the Maerum, possibly through some form of telepathy.
Curiously, Tanyenn seems to fare best in areas where Maerum and Alatien communities are both present. Considering how beneficial the Tanyenn and the Maerum/Alatien are to each other, it is quite possible that, like the common ancestors of the two races, Tanyenn was brought to Earth by the Blue Kin.
Tanyenn can be obtained from the home of the Maerum Queen.