Diaphyodus sauvagei

Diaphyodus sauvagei

(Leriche, 1900)

Common name Drumfish relative
Fossil group Bony Fish
Order Perciformes
Family incertae sedis
Genus Diaphyodus
Taxonomic status Taxonomically Uncertain
Geological age Ypresian

Summary

Diaphyodus sauvagei was an early Eocene bony fish known primarily from robust pharyngeal dentitions. It was historically treated as a wrasse, but modern review excludes it from Labridae and retains Diaphyodus within Perciformes with only tentative sciaenid, or drumfish, affinity.

The upper and lower pharyngeal tooth plates indicate a specialised crushing apparatus, so a durophagous feeding role on hard-shelled or otherwise resistant prey is a reasonable functional inference. Body form, swimming mode and precise habitat position cannot be reconstructed confidently from isolated dental material alone.

Quick Identification

Look for: a robust pharyngeal tooth plate carrying closely set low, rounded crushing teeth rather than an ordinary jaw row of pointed teeth. Plate outline and the arrangement and relative size of teeth matter more than a detached individual tooth; fragmentary or heavily worn isolated teeth should normally remain at a broader durophagous-fish identification.

Diagnostic Features

  • Dentition is borne on a compact pharyngeal tooth plate rather than as a simple marginal jaw row.
  • Functional teeth are low and rounded to blunt, forming a crushing surface rather than narrow piercing cusps.
  • Both upper and lower pharyngeal plates form part of the species concept and must be compared with the appropriate plate position.
  • Tooth size and spacing vary across the plate, so the preserved arrangement is more informative than a detached single tooth.
  • Species-level identification requires agreement of plate outline and tooth arrangement with published Diaphyodus material; isolated worn teeth alone are not diagnostic.

Fossil Details

Typical size
Not reliably established from the published isolated pharyngeal plates.
Fossil material
Tooth Plate
Preservation
Pharyngeal plates commonly survive as broken pieces with missing margins or detached crushing teeth. Functional wear can flatten tooth tops, and abrasion can obscure the original tooth-plate pattern; species-level identification is strongest where enough of the plate outline and tooth arrangement remain.

Similar Species

Recorded Fossil Sites

Synonyms & Previous Names

Nummopalatus sauvagei; Labrodon sauvagei

References

  • Bellwood, D.R.; Schultz, O.; Siqueira, A.C.; Cowman, P.F. (2019). A review of the fossil record of the Labridae. Annalen des Naturhistorischen Museums in Wien, Serie A, 121, 125–193 View reference
  • White, E.I. (1931). The vertebrate faunas of the English Eocene. I. From the Thanet Sands to the Basement Bed of the London Clay. 121 pp.. British Museum (Natural History), London View reference
Last Reviewed
21 August 2026 Reviewed by Sam Harris