Icacinicarya nodulifera

Icacinicarya nodulifera

Reid et Chandler

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

Summary

Icacinicarya nodulifera was a small icacinaceous fruit with an oval, laterally compressed stone. The surviving endocarp looks comparatively plain externally, but its coarse ridged or faceted locule cast suggests that the original wall may have carried more relief than is visible on the weathered fossil. The stone protected a single seed in the same basic way as other drupaceous members of Icacinaceae.

This Species demonstrates why preservation must be separated from biology in the London Clay flora. The modern CT study could confirm its icacinaceous construction, but could not reliably reconstruct every surface or vascular character because pyritisation and abrasion have degraded the material. Its whole-plant habit is likewise unknown. The safest interpretation is therefore a distinct Icacinicarya fruit morphotype rather than an attempt to force it into a living genus.

Quick Identification

Look for: a small, nearly oval endocarp about 14 mm long with a lenticular cross-section and a coarse ridged/faceted locule cast. A smooth-looking outer surface is not reliable because abrasion may have removed the original relief.

Diagnostic Features

  • Endocarp is oval in side view and lenticular in transverse section.
  • Typical dimensions are about 14 mm long, 13 mm wide and 8 mm thick.
  • Locule cast is coarsely ridged or faceted rather than finely papillate in gross relief.
  • Outer surface may appear smooth or weakly nodular, but this is probably strongly affected by abrasion.
  • Marginal vascular-bundle position is ambiguous in modern CT data and should not be used alone for identification.

Fossil Details

Typical size
Approximately 14 × 13 × 8 mm.
Fossil material
Seed, Fruit
Preservation
The available material is strongly affected by abrasion and pyrite alteration. Surface ornament and the exact vascular-bundle position are uncertain, so specimens should not be identified simply because they are small, oval and smooth.

Similar Species

Recorded Fossil Sites

No fossil-site occurrences have yet been recorded for this species.

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
  • 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