[Palaeontology, Vol. 53, Part 5, 2010, pp. 1077–1098] HIGH CONCENTRATION OF LONG-SNOUTED BEAKED WHALES (GENUS MESSAPICETUS)FROM THE MIOCENE OF PERU by GIOVANNI BIANUCCI*, OLIVIER LAMBERT à and KLAAS POST§ *Dipartimento di Scienze della Terra, Universita` di Pisa, via S.Maria, 53, I-56126 Pisa, Italy; e-mail
[email protected] De´partement de Pale´ontologie, Institut royal des Sciences naturelles de Belgique, Rue Vautier, 29, B-1000 Brussels, Belgium àPresent address: De´partement Histoire de la Terre, Muse´um National d’Histoire Naturelle, Rue Buffon, 8, F-75005 Paris, France; e-mail
[email protected] §Natuurhistorisch Museum Rotterdam, PO Box 23452, 3001 KL Rotterdam, The Netherlands; e-mail klaaspost@fishcon.nl Typescript received 18 May 2009; accepted in revised form 4 December 2009 Abstract: Eight skulls of beaked whales (Cetacea, Odonto- cent of the medial margin of the maxilla from the vertex. A ceti, Ziphiidae), in six cases associated with elements of the parsimony analysis reveals that Messapicetus belongs to a mandible, were collected from a limited area (about 1.5 km2) basal clade, which includes other ziphiids with a dorsally and roughly from the same stratigraphic horizon at Cerro closed mesorostral groove and prenarial basin. The high con- Colorado, 35 km south-south-west of the city of Ica (Peru), centration of specimens belonging to the same species (some where the late Middle Miocene basal strata of the Pisco For- of them tentatively identified as adult males and females), mation crop out. They represent the highest concentration combined with the presence of a calf, supports the hypothe- reported of fossil Ziphiidae.