Brasilennea arethusae is a fossil species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Cerionidae, from the Paleocene Itaboraí Basin, Brazil.Salvador, R.B.; Rowson, B.; Simone, L.R.L. 2011. Rewriting the fossil history of Cerionidae (Gastropoda: Pulmonata): new family assignment of the Brazilian Palaeocene genus Brasilennea Maury, 1935. Journal of Molluscan Studies 77: 445–447. Brasilennea arethusae is the largest species in the genus Brasilennea. It was one of the first fossils found in Itaboraí Basin and its name makes reference to the fact that it is a terrestrial species: the name is in honor of Arethusa, a sylvan nymph and one of the Hesperides from Greek mythology.
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