Trichomanes speciosum Trichomanes speciosum – Killarney Fern Found in Cool Fernery Glasshouse at Chelsea Physic Garden Trichomanes speciosum is long-lived, with delicate, translucent fronds that are only one cell thick. It is a native to the UK, Europe, the Canary Islands and the Azores. It grows in very deeply shaded habitats such as large dripping caves, crevices in cliffs and small caves, and on dripping vertical cliffs and rocky banks in wooded ravines. This fern has always been a rare species in the UK and exists as either a ‘gametophye’ which looks a little like moss or a ‘sporophyte’ that has fronds. The sporophyte generation that grows at the Garden is only found in 16 UK locations in the wild. The main threat to these ferns in the British Isles has been from collecting, particularly during the Victorian era of ‘Pteridomania’. It became a protected species in the UK in 1975 under the Conservation of Wild Creatures and Wild Plants Act. Find out more about our Glasshouse Restoration Project.