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A large number of higher taxa contain species restricted to subterranean habitats, and most of these species show con-vergent differentiation in a suite of features related to the absence of light [1,2]. These features, termed troglomorphy by Christiansen 1962 [3], include partial to complete loss of eyes and body pigment, elaborated extra-optic sensory structures, elongated appendages, and more slender body forms compared to related surface-dwelling taxa. The elab-orated and elongated features are generally assumed to be adaptations to the aphotic environment from selection for enhanced extra-optic sensory performance and efficiency of movement, and are considered as textbook examples of evolution by means of natural selection. The reduction to loss of eyes and body pigment in subterranean species is part of a universal phenomenon of vestigialization to los