Its type species, E. gastaldii, had a complex taxonomic history, starting as a cetothere, then as an extinct member of Balaenoptera, before being finally recognized as a relative of the gray whale.

Its holotype, MRSN 13802, comes from the early Pliocene-age Sabbie d'Asti Formation of the Piedmont region in Italy [1] and it is currently exposed in Asti's paleontological museum "Museo Paleontologico Territoriale dell'Astigiano".

After four days of digging they had unveiled a giant skeleton easily identifiable as a whale 12 feet 5 inches long.

Cortesi noted that at that time few naturalists could assign cetacean fossils to individual species, and he therefore never named his specimen.

Desmoulins 1822[6] thought the "Baleine de Cortesi" represented a distinctive species because it was a very small adult individual and because the curvature of the maxillary branches was less convex than in any other known whale.