Macrosqualodelphis

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Macrosqualodelphis
Temporal range: Burdigalian
~18.78  Ma
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Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Squalodelphinidae
Genus: Macrosqualodelphis
Bianucci et al. 2018
Species:
M. ukupachai
Binomial name
Macrosqualodelphis ukupachai
Bianucci et al. 2018

Macrosqualodelphis is an extinct genus of river dolphins from the Early Miocene (Burdigalian) Chilcatay Formation of the Pisco Basin, Peru. The type species is M. ukupachai.

Description

Macrosqualodelphis is distinguished from other squalodelphinids by its larger size (3.5 metres (11 ft)) and a less abrupt anterior tapering of rostrum in dorsal view, U-shaped left antorbital notch prominent nuchal crest higher than the frontals and nasals at the vertex, a thinner, blade-like lateral margin of the posterior portion of the rostrum, and a more voluminous temporal fossa and larger teeth. [1]

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References

  1. Giovanni Bianucci, Giulia Bosio, Elisa Malinverno, Christian de Muizon, Igor M. Villa, Mario Urbina and Olivier Lambert. 2018. "A New Large Squalodelphinid (Cetacea, Odontoceti) from Peru Sheds Light on the Early Miocene Platanistoid Disparity and Ecology" Archived 2018-08-13 at the Wayback Machine . Royal Society Open Science. 5(4) DOI: 10.1098/rsos.172302 CC-BY icon.svg Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.