Light and electron photomicroscopy were used to study variability in eye regression of populations of a cavernicolous gryllid cricket from Northern Venezuela. Statistical analysis suggests there are two distinct types or subspecies each with a separate habitat preference. The micropthalmic type is probably better adapted to life in low-energy, deep-cave environments but is outcompeted in high-energy environments (e.g. Guano beds) by the macropthalmic type.