Thunnosauria
extinct clade of ichthyosaurs
Thunnosauria (Greek for "tuna lizard" – thunnos meaning "tuna" and sauros meaning "lizard") is an extinct clade of parvipelvian ichthyosaurs from the Early Jurassic to the early Late Cretaceous (Hettangian–Cenomanian) of Asia, Australia, Europe, North America, and South America. Named by Ryosuke Motani in 1999, it contains the basal taxa Ichthyosaurus and Stenopterygius and the family Ophthalmosauridae. In thunnosaurs, the fore fin is at least twice as long as the hind fin.
Phylogeny
Thunnosauria is a node-based taxon defined in 1999 as "the last common ancestor of Ichthyosaurus communis and Stenopterygius quadriscissus and all of its descendants". The cladogram below follows the topology from a 2010 analysis by Patrick S. Druckenmiller and Erin E. Maxwell.
The public source identifies “Thunnosauria” as extinct clade of ichthyosaurs. This brief keeps that definition visible, then builds a research path around Thunnosauria, extinct and clade.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Thunnosauria”, the useful work is to connect “extinct clade of ichthyosaurs” to the records capable of establishing context and consequence.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jul 1, 2025. The linked authority identifier is Q3281279. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1999 and 2010.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
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Three-step research path
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- Expand the search: follow Thunnosauria primary sources, Thunnosauria archive and Thunnosauria research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
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This entry incorporates text from “Thunnosauria” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.