Texas Shrews (Blarina hylophaga) Lacking External Eye Openings

Abstract

Shrews are insectivorous opportunistic foragers occupying moist habitats characterized by high vegetative composition. Shrews characteristically have poorly developed eyesight and rely on olfactory and auditory senses for efficient foraging. Two Blarina hylophaga (Elliot's short-tailed shrew) recently trapped in East Texas did not have externally visible eyes. Further examination during specimen preparation revealed both had developed eyes, but lacked developed, opened, or functional eyelids. A third shrew, collected in Bastrop County, TX, had developed eyes and eyelids, however, the external openings were abnormally small. All three shrews were adults and alive in traps, suggesting no ill effects due to the reduction or absence of eye openings and further suggesting little or no effect on the survival of these individuals.