Ekalakia (Decapoda: Brachyura): The Preservation of Eyes Links Cretaceous Crabs to Jurassic Ancestors

Abstract Description of a new species of crab, Ekalakia exophthalmops, brings to two the number of species within this Late Cretaceous genus from the upper mid-west in North America. Discovery of eyes and orbital structures in both species permits placement of the genus within the superfamily Glaessneropsoidea Patrulius, 1959 and family Glaessneropsidae Patrulius, 1959, extending the range of those taxa from the Late Jurassic into the Late Cretaceous. The extraordinarily large eyes relative to body size suggests that the Jurassic reef-dwelling crabs were adapted for a cryptic lifestyle which preadapted them for the deep-water, dysphotic, level-bottom habitat occupied by the Cretaceous descendants.