Stygofauna are aquatic animals that live in groundwater, often at considerable depths below the ground surface. While some of the best-known species occupy lakes in subterranean caves, most stygofauna species occur in alluvial, karstic or fractured rock aquifers. They occupy the interstitial spaces, vugs and fissures in these aquifers. Most stygofauna are invertebrate crustaceans but there are also stygal mites, worms, snails and beetles, as well as a few fish and amphibians. Because they live in the absence of light, stygofauna lack eyes and pigmentation. The Pilbara is a global hotspot for stygofauna, and their evolution and existence over millions of years is indicative of the longevity and importance of groundwater in the Pilbara environment. Bennelongia staff have many years of policy and research experience in stygofauna surveys and identification and ecological impact assessments and reviews.