Temporal range: Upper Triassic – Recent
The Prototheria is a former subclass of mammals, now no longer in use. The name comes from Greek prōtos means 'first', and thēr, 'beast'. The only surviving animals in this subclass are the Monotremes.
There are two other subclasses, the Metatheria and the Eutheria. Metatheria contains the marsupials. All the other mammals are Eutherian.
Evidence is accumulating that the Prototheria is not a natural group, but alternative suggestions are not yet agreed. The term is not listed in Benton's 4th ed (2015), so it is now a dead term.
References[change | change source]
- ↑ Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo 2004. Mammals from the Age of Dinosaurs: origins, evolution, and structure. New York: Columbia University Press.
- ↑ Benton, Michael J. 2005. Vertebrate palaeontology. 3rd ed. Oxford: Blackwell Publishing. ISBN 0-632-05637-1