Cashel Loughs is an extensive area of semi-natural vegetation in an ice-scoured rock basin. It takes in a wide range of habitats including dry heath, acid grassland, scrub and woodland.The wetlands are of particular importance, with a range of communities including the clear unpolluted open waters of the three loughs in addition to adjoining fen, cut-over bog, wet heath and rush pasture. The area contains a number of vascular plants with a restricted distribution in Ireland and Britain, including marsh St. John’s-wort, western gorse and a number of notable mosses, as well as common reed, water horsetail and white water lily.
The diversity of wetland habitats supports a rich invertebrate community including 30 species of water beetle, 15 species of spider and 10 species of ground beetle. In addition to its overall diversity, the site contains a number of notable species including the rove beetle Stenus nitens, the water beetle Laccornis oblongus and four species of spider.