Argentina tricrenulata

Argentina tricrenulata

(Stinton, 1965)

Common name Argentine fish
Fossil group Bony Fish
Order Argentiniformes
Family Argentinidae
Genus Argentina
Taxonomic status Accepted
Geological age Thanetian

Summary

Argentina tricrenulata was a Palaeogene argentinid, part of the marine lineage represented today by argentines. It is known primarily from sagittal otoliths. Modern revision restores Stinton’s species under Argentina and distinguishes it nomenclaturally from material fixed under the older name Argentina erratica.

Its otolith is thin and broadly pentagonal, with a conspicuous postdorsal angle and a long narrow sulcus. These features provide a more reliable basis for identification than size, colour or a single broken margin.

Quick Identification

Look for: a thin, broadly pentagonal otolith only a few millimetres long, with a massive pointed rostrum, a sharp postdorsal angle and a long narrow supramedian sulcus whose cauda extends far toward the posterior margin.

Diagnostic Features

  • Otolith is thin and broadly pentagonal, with five principal angles around the outline.
  • Rostrum is massive and pointed; a distinct excisura and antirostrum are absent.
  • Postdorsal angle is conspicuous and sharper than the rounded predorsal and posterior angles.
  • Sulcus is long, narrow and supramedian; the cauda is about twice the length of the short ostium and reaches far posteriorly.
  • Outer face is nearly flat and smooth, while the inner face is comparatively flat with a marked dorsal depression.

Fossil Details

Typical size
Published adult otoliths are only a few millimetres long and reach about 4 mm.
Fossil material
Otolith
Preservation
The otolith is thin and can break at the rostrum, postdorsal angle or posterior margin. Abrasion may round the postdorsal angle and soften the sulcus margins, making worn specimens difficult to separate from other small argentinids. Juvenile specimens can also differ in outline from adults.

Recorded Fossil Sites

Reculver Sand Member

Thanet Formation
Confirmed
Reculver

Synonyms & Previous Names

Primaevomesus tricrenulatus

References

  • Schwarzhans, W.; Mörs, T.; Engelbrecht, A.; Reguero, M.; Kriwet, J. (2017). Before the freeze: otoliths from the Eocene of Seymour Island, Antarctica, reveal dominance of gadiform fishes (Teleostei). Journal of Systematic Palaeontology, 15(2), 147–170 View reference
  • Stinton, F.C. (1965). Teleost otoliths from the Lower London Tertiaries. Senckenbergiana Lethaea, 46a, 389–425 View reference
  • Ward, D.J. (1978). The Lower London Tertiary (Palaeocene) succession of Herne Bay, Kent. Report of the Institute of Geological Sciences. Institute of Geological Sciences View reference
Last Reviewed
22 August 2026 Reviewed by Sam Harris