Isoetes malinverniana

Isoetes malinverniana is found only in the Ticino and Po rivers in northern Italy and is critically endangered in the wild, making its cultivation in the aquarium hobby a genuine act of botanical conservation. It produces longer, more flexible and graceful quill-shaped leaves than I. lacustris, arranged in a spreading fountain rosette. Like all Isoetes it requires cool, very clear, soft water with bright light and CO2, placing it firmly in the specialist category — but its rarity and beauty justify the effort.