Outline of undescribed specimens MPTA 207-13307 This specimen represents a new genus and species of Balaenopteridae whose description is now complete. It includes an incomplete skull with periotic still in articulation and part of the postcrania. The estimated age is earliest Piacenzian. NMR 999100007096 This specimen includes skull, periotic and part of the postcrania. Its morphology suggests a close relationship to ‘Balaenoptera’ portisi. In the remainder of the paper and in the illustrations it is called NMR 7096. The estimated age is early Piacenzian. RBINS M. 2231 This specimen includes skull, periotics, dentaries and part of the postcrania. It is closely related to ‘Balaenoptera’ sibbaldina of which it represents the first reasonably complete skeleton. The specimen is briefly presented in Bisconti & Bosselaers (2014) and a full description is currently in progress. The specimen is currently held by RBINS. The estimated age is Early Pliocene. RBINS M. 2315 The specimen includes partial skull and postcrania of a Pliocene individual very close to Protororqualus cuvieri. The description of this specimen is currently in progress. MHNL 1613 The specimen includes a large skull with periotics still in articulation. It represents a new balaenopterid genus characterized by wide exposure of parietal at the cranial vertex. A description is currently close to be finished. The estimated age is Late Miocene. MHNL 1610 The specimen includes a partially prepared skull with fragments of dentary. Its morphology suggests close relationships with Archaebalaenoptera castriarquati of which it could be an additional species. A description is currently in progress. The estimated age is Late Miocene.