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Australia's Marsupial Tree Gains a Sixth Branch
Three fossil species may belong to Keeunamorphia, an ancient lineage that persisted for roughly 35 million years.
Summary
Three fossil species may belong to Keeunamorphia, an ancient lineage that persisted for roughly 35 million years.
A University of New South Wales analysis of teeth and jaw fragments from Queensland's Riversleigh fossil deposits proposes a sixth Australian marsupial order. The three species lived about 18 million years ago, but their teeth resemble the much older Djarthia murgonensis, supporting a lineage that may have split early and survived for tens of millions of years. The classification rests on fragmentary fossils and a reconstructed evolutionary tree, so it is a proposal about deep relationships rather than a complete ancestry.
Why it matters
Three fossil species may belong to Keeunamorphia, an ancient lineage that persisted for roughly 35 million years.
Limits and context
No additional limitation was separately recorded.
Key claims
Three fossil species may belong to Keeunamorphia, an ancient lineage that persisted for roughly 35 million years.
Evidence: source-2026-07-19-004
Sources
- University of New South Wales via ScienceDaily: KeeunamorphiaUniversity of New South Wales via ScienceDaily · secondary reporting
Corrections
No corrections have been recorded for this story.