Nalacetus

Nalacetus Temporal range: Early Eocene,
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Infraorder:	Cetacea
Family:	†Pakicetidae
Genus:	†Nalacetus Thewissen & Hussain 1998
Species:	†N. ratimitus
Binomial name
†Nalacetus ratimitus Thewissen & Hussain 1998

Nalacetus is an extinct pakicetid early whale, fossils of which have been found in Lutetian red beds in Punjab, Pakistan (33.6°N 72.2°E / 33.6; 72.2, paleocoordinates 14.3°N 68.3°E / 14.3; 68.3). Nalacetus lived in a fresh water environment, was amphibious, and carnivorous. It was considered monophyletic by Cooper, Thewissen & Hussain 2009. It was said to be wolf-sized and one of the earliest forms of the order Cetacea.

Nalacetus is known mostly from dental remains from the Lutetian of the Kala Chitta Hill, Punjab, Pakistan:

• H-GSP 96055, right palatal fragment with P⁴ and M¹⁻².
• H-GSP 30306, right maxillary fragment with P² and partial P³⁻⁴; a fragmentary mandible with fragmented teeth together with some isolated lower teeth.

In the cheek teeth of Pakicetus, the protocone lobe increases from the first molar to the third. In Nalacetus, in contrast, the protocone lobe is larger in the first molar than in the second.

References

• Cooper, Lisa Noelle; Thewissen, J. G. M.; Hussain, S. T. (2009). "New middle Eocene archaeocetes (Cetacea: Mammalia) from the Kuldana Formation of northern Pakistan" (PDF). Journal of Vertebrate Paleontology. 104 (4): 1289–99. Bibcode:2009JVPal..29.1289C. doi:10.1671/039.029.0423. OCLC 506008976. S2CID 84127292. Archived from the original (PDF) on 14 July 2012. Retrieved 1 June 2013.
• Thewissen, J. G. M.; Hussain, S. T. (1998). "Systematic review of the Pakicetidae, Early and middle Eocene Cetacea (Mammalia) from Pakistan and India". Bulletin of the Carnegie Museum. 34: 220–38.