An unfamiliar physeteroid periotic (Cetacea: Odontoceti) from the German middle–late Miocene North Sea basin at Groß Pampau

Abstract

Abstract. The Miocene mica clay locality of Groß Pampau, known for numerous and partly spectacular finds of marine mammals is becoming more and more a prominent site that bears the potential to resolve questions regarding taphonomic relationships and to interpret life communities of the ancient North Sea because of its rich faunal assemblage including invertebrates and other remains of various vertebrate organisms. In the present work we describe a right periotic of Physeteroidea with morphological characters so far unknown from other sperm whales. The periotics of the middle Miocene Aulophyseter morricei demonstrate the closest resemblance to the Groß Pampau specimen in their overall appearance and in the general arrangement and proportions of single structures, particularly of the anterior process and pars cochlearis. A great similarity is also documented with periotics of the living sperm whale, Physeter macrocephalus, especially regarding the shape and disposition of the anterior process and the bony element located dorsally to the accessory ossicle. Kogiid periotics differ strongly from that of the Groß Pampau specimen by having an inflated and short anterior process and, typically, three well-defined spines on it. A new taxonomic naming of the Groß Pampau periotic is not appropriate at this stage, although it might demonstrate the existence of a so-far undescribed physeteroid species. Additionally, its systematic position remains yet unclear and it is unknown at this point if it could belong to Hoplocetus ritzi, another physeterid, whose fragments were discovered in the same locality, or to another, already-described taxon, of which the periotic is still unknown.

First records of extinct kentriodontid and squalodelphinid dolphins from the Upper Marine Molasse (Burdigalian age) of Switzerland and a reappraisal of the Swiss cetacean fauna

“…Of the four characters relevant to the periotic mentioned in the phylogenetic analysis of Lambert, Bianucci & De Muizon (2017) , NMBE 5036437 shares with other physeteroids the very small anterior bullar facet and the enlarged accessory ossicle (judged by the size of the fovea epitubaria). The accessory ossicle is fused to the periotic in some physeteroids (e.g., the Gross Pampau physeteroid in Montañez Rivera & Hampe, 2020 ), but not in NMBE 5036437 (accessory ossicle missing). The posterior part of the posterior process of NMBE 5036437 is directed posteroventrally as in other physeterids and unlike in kogiids.…”

The so‐called foramen singulare in cetacean periotics is actually the superior vestibular area

“…As mentioned above, the foramen singulare in mammals lies ventral to the transverse crest in the fundus of the internal acoustic meatus. The position of the foramen singulare relative to the transverse crest in cetaceans, however, has been variably interpreted among species: in some, it is considered as being dorsal to the transverse crest, and in others, being ventral to the crest (e.g., Aguirre‐Fernández & Fordyce, 2014; Boessenecker & Fordyce, 2015, 2017; Ichishima, Furusawa, Tachibana, & Kimura, 2019; Ichishima & Kimura, 2005; Kasuya, 1973; Kellogg, 1936; Kimura & Hasegawa, 2019; Lambert, Bianucci, & de Muizon, 2017; Lambert, Bianucci, & Urbina, 2014; Lambert, Godfrey, & Fitzgerald, 2019; Montañez‐Rivera & Hampe, 2020; O'Leary, 2010; Tanaka, Abella, Aguirre‐Fernández, Gregori, & Fordyce, 2017; Tanaka & Fordyce, 2014, 2015; Viglino, Buono, Gustein, Cozzuol, & Cuitiño, 2018).…”

“…Interestingly, essentially no reference about the presence or absence of the superior vestibular area in cetacean periotics has been made to (with some exception based on misunderstanding for the orientation of the petrosal, upside down, viz. the inferior vestibular area labeled as the superior vestibular area) (e.g., Montañez‐Rivera & Hampe, 2020), in spite of being an obvious component in a quadrant of the fundus of the internal acoustic meatus in mammals. Mead and Fordyce (2009), which has become widely cited in the field of cetacean paleobiology and osteology, referred to the dorsal (=superior) vestibular area, and mentioned that in Tursiops the ventral vestibular area includes the spiral cribriform tract.…”

Influence of abiotic and biotic factors on benthic marine community composition, structure and stability: a multidisciplinary approach to molluscan assemblages from the Miocene of northern Germany

“…Over the past 40 years, excavations yielded highly diverse marine fossil assemblages, which include marine mammals (mainly mysticetes, odontocetes and pinnipeds), remains of cheloniid and dermochelyid sea turtles, teeth and skeletal elements of elasmobranchs, teleost otoliths, and more than 140 species of mollusc (Moths 1989, 1990, 1992, 1994, 1995, 1998, 2003; Höpfner 1991, 2014; Behrmann 1995; Lierl 1995; Hampe 1999, 2006; Kazár & Hampe 2014; Kriwet et al . 2015; Montañez‐Rivera & Hampe 2020).…”