Abstract This paper records the first occurrence of the genus Myrmicium Westwood, 1854 in the Cretaceous of Gondwana and describes it as a new species Myrmicium araripterum sp. nov, based on the most complete specimen of this genus yet known, which represents the largest specimen of the grade “Symphyta” ever found in the Crato Formation.

ABSTRACT The Romualdo Member of the Santana Formation, a lithostatigraphic unit attributed to a marine intrusion, is famous for its preserved fossils in calcareous concretions, which stand out for their diversity and excellent preservation levels. This paper aims to record the first occurrence of the Class Insecta in the Romualdo Member of the Santana Formation of the Araripe Basin, as well as to describe and discuss the paleo-ecological implications of such finding. The first occurrence of the order Orthoptera (family Gryllidae) is presented for this unit. This new species is attributed to the genus Araripegryllus, that lasted throughout the deposition of the Crato Member, which is under the Romualdo Member. In reference to its statigraphic origin, the specimens was named Araripegryllus romualdoi sp. nov.