Iodes eocenica

Iodes eocenica

Reid et Chandler

Fossil group Plants
Order Icacinales
Family Icacinaceae
Genus Iodes
Taxonomic status Accepted
Geological age Ypresian

Summary

Iodes eocenica was an early Eocene icacinaceous plant known from a relatively broad, flattened fruit stone. The substantial endocarp formed a tough protective wall around the seed, and the inner seed cavity preserved a finely papillate lining.

Its placement in Iodes is accepted from the combination of preserved anatomy and well-documented earlier observations. Some material has deteriorated too far for modern imaging to confirm every internal feature again, so the historic anatomical record remains important. No attached stems or leaves are known, and the whole-plant growth form is therefore not directly preserved.

Quick Identification

Look for: a broad oval, flattened Iodes stone about 14–15 mm long, with a coarse network of broad rounded ridges and a finely papillate locule lining. The embedded marginal bundle is historically documented but may not be recoverable in degraded modern specimens.

Diagnostic Features

  • Endocarp is circular to broadly oval in lateral view and strongly lenticular in cross-section.
  • Surface bears a coarse reticulum of broad rounded ridges enclosing small areoles or concavities.
  • Wall is relatively thick and contains interlocking digitate cells.
  • Locule lining is finely papillate.
  • An embedded marginal vascular bundle was documented in the original material, although modern CT could not reliably re-image it.

Fossil Details

Typical size
About 13.5–15 mm long, around 12 mm wide and approximately 5–6 mm thick.
Fossil material
Seed, Fruit
Preservation
The specimens available to the modern revision are degraded, especially along the margin, so the vascular-bundle course cannot always be seen. Abrasion can also reduce the broad ridge network; combine gross form, sculpture and locule lining rather than relying on one feature.

Similar Species

Recorded Fossil Sites

References

  • Eleanor Mary Reid; Marjorie Elizabeth Jane Chandler. (1933). The London Clay Flora. . British Museum (Natural History), London View reference
  • Gregory W. Stull; Neil F. Adams; Steven R. Manchester; Dan Sykes; Margaret E. Collinson. (2016). Revision of Icacinaceae from the Early Eocene London Clay flora based on X-ray micro-CT. Botany, 94(9), 713–745 View reference
  • Kathleen B. Pigg; Steven R. Manchester; Melanie L. DeVore. (2008). Fruits of Icacinaceae (Tribe Iodeae) from the Late Paleocene of western North America. American Journal of Botany, 95(7), 824–832 View reference
  • Margaret E. Collinson; Neil F. Adams; Steven R. Manchester; Gregory W. Stull; Fabiany Herrera; Selena Y. Smith; Mary J. Andrew; Paul Kenrick; Dan Sykes. (2016). X-ray micro-computed tomography (micro-CT) of pyrite-permineralized fruits and seeds from the London Clay Formation (Ypresian) conserved in silicone oil: a critical evaluation. Botany, 94(9), 697–711 View reference
Last Reviewed
26 August 2026 Reviewed by Sam Harris