Tuesday, September 7, 2021

[PaleoMammalogy • 2021] Marzanoptera tersillae • A New Balaenopterid Genus and Species (Mysticeti: Balaenopteridae) from the Pliocene of Piedmont, north-west Italy


 Marzanoptera tersillae 
Bisconti, Damarco, Pavia, Sorce & Carnevale, 2021

Marzanoptera tersillae gen. & sp. nov., a new balaenopterid from the Pliocene of the Piedmont in north-west Italy, is described based on a partial skeleton and compared with other living and fossil baleen whales. Marzanoptera tersillae shares characters, such as the shape of the supraoccipital, glenoid fossa of the squamosal and zygomatic process of the squamosal, with ‘Balaenopterabertae. We used a computed tomography scan to view parts of the skull that were otherwise impossible to observe, such as the periotic. A phylogenetic analysis based on 355 character states scored from 87 taxa revealed a well-resolved hypothesis of relationships for Balaenopteridae and a general phylogenetic hypothesis for chaeomysticetes. The monophyly of all superfamily- and family-rank clades and of crown balaenopterid species was confirmed. In addition, a monophyletic group including most basal thalassotherian taxa was recovered. The mollusc fauna associated with the specimen was autochtonous and constituted a residual fossil assemblage indicative of an environmental context located below the base of the storm wave, characterized by a low-energy hydrodynamic regimen. Many shark teeth have been found in close association or embedded within the bones, suggesting a possible scavenging action by two shark species on the whale carcass.

Keywords: Balaenopteridae, phylogeny, taphonomy, whale falls


Class Mammalia Linnaeus, 1758 
Order Cetacea Brisson, 1762 
Suborder Mysticeti Flower, 1865 
Infraorder Chaeomysticeti Mitchell, 1989 
Parvorder Balaenomorpha Geisler & Sanders, 2003 

Superfamily Thalassotherii Bisconti, Lambert & Bosselaers, 2013 
Epifamily Balaenopteroidea Gray, 1868 
Family Balaenopteridae Gray, 1864 

Genus Marzanoptera gen. nov. 

Etymology: The genus name is composed of Marzano-, shortened from San Marzanotto, the locality of the discovery of the holotype skeleton, and the Greek φτερόwing, referring to the wide and long forearms of balaenopterid whales. 

Map showing the distribution of the bones of the holotype skeleton of  Marzanoptera tersillae. In this and subsequent figures, see ‘Anatomical abbreviations’ subsection of the main text for explanations of abbreviations. Scale bar: 500 mm.

Holotype skull of  Marzanoptera tersillae in lateral view.
 A, photographic representation of the skull in right lateral view.
B, anatomical interpretation.
C, photographic representation of the skull in left lateral view.
D, anatomical interpretation.
Scale bar: 10 cm.

Marzanoptera tersillae sp. nov.

Etymology: The fossil skeleton was discovered by Tersilla Argenta, for whom it was named. 

Holotype: Specimen 207.13307 of the inventory of EGPPA-MPTA institution in Asti. The specimen includes most of the skull, with one periotic in articulation, seven vertebrae and nine ribs. 

Michelangelo Bisconti, Piero Damarco, Marco Pavia, Barbara Sorce and Giorgio Carnevale. 2021. Marzanoptera tersillae, A New Balaenopterid Genus and Species from the Pliocene of Piedmont, north-west Italy. Zoological Journal of the Linnean Society. 192(4); 1253–1292. DOI: 10.1093/zoolinnean/zlaa131