Kollikodontidae

fossil monotreme family

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 16, 2026

Quick Summary

The Kollikodontidae family is known from fossil jaw fragments found in Australia, dating back to the early Cretaceous Period. This family, along with Steropodontidae, represents extinct monotremes, which are egg-laying mammals. The most notable species, Kollikodon ritchiei, possessed unique rounded cusps on its molar teeth, suggesting a greater diversity among Cretaceous monotremes than previously understood. These discoveries indicate that monotremes may have been the dominant mammals in the ancient supercontinent of Gondwanaland. The order Monotremata, which includes modern platypuses and echidnas, is the most ancient living order of mammals.1

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

monotreme
Paleontology and classification
…galmani), and the uniquely specialized Kollikodontidae, which is also represented by a single species (Kollikodon ritchiei). Both are known only from opalized jaw fragments. The strange rounded cusps on the molar teeth of K. ritchiei were a surprise to paleontologists, suggesting that Cretaceous monotremes may have been more diverse and…
Read More
…galmani), and the uniquely specialized Kollikodontidae, which is also represented by a single species (Kollikodon ritchiei). Both are known only from opalized jaw fragments. The strange rounded cusps on the molar teeth of K. ritchiei were a surprise to paleontologists, suggesting that Cretaceous monotremes may have been more diverse and…
Read More