Rock shelters, tunnels and perpetually dark caves occur in large numbers in Sri Lanka. Their importance to food security, public health and sustainable economies has largely gone unnoticed and unexplored by scientists, researchers and naturalists. Throughout history, these perpetually dark caves have been feared, respected and admired but their biota has for long years gone unnoticed because naturalists reasoned that conditions in them were too tough for life. Since 1689 when the eyeless salamander (Proteus anguinus) was discovered in a dark cave in Slovenia in south central Europe, many countries have focused on cave biodiversity and have recorded insects, crustaceans, molluscs, chilopods, diplopods, arachnids, fish, amphibians, bats, reptiles and birds.
With a view to exploring hidden biodiversity in the dark caves of Sri Lanka, Dilmah Conservation partnered with Biodiversity Sri Lanka and the Lanka Institute of Cave Science (LICAS) to document the diverse range of organisms that inhabit these dark, understudied structures.