Stizocarya communis
Stizocarya communis
Summary
Stizocarya communis was a small, subglobose to ovoid icacinaceous fruit with an unusual perforated endocarp. Numerous narrow cylindrical channels run through the wall from the external surface to the seed cavity. Unlike the pitted fruits of Palaeophytocrene, however, these channels do not terminate in large tubercles projecting into the locule, giving Stizocarya a fundamentally different internal architecture.
The wall is thick, the principal marginal vascular bundle is embedded for most of its course, and the locule lining is made from relatively large interlocking, star-like or digitate cells rather than an ordinary field of fine papillae. These anatomical traits justify a distinct fossil genus. The fruit protected a single seed, but its soft outer tissues and vegetative organs are unknown; no specific growth habit should therefore be assigned beyond its secure membership in the woody Icacinaceae lineage.
Quick Identification
Look for: a subglobose/ovoid stone about 11–14.5 mm across with many narrow cylindrical pits or channels penetrating the entire wall. CT/sectioning is decisive: the channels reach the locule but do not form the large inward tubercles seen in Palaeophytocrene.
Diagnostic Features
- Endocarp is subglobose to ovoid, generally about 11–14.5 mm in diameter.
- Wall is thick, commonly around 1.5–2 mm.
- Numerous narrow cylindrical channels pass completely through the wall from surface to locule.
- Channels do not terminate in conspicuous tuberculate projections into the locule.
- Locule lining consists of large interlocking digitate or star-shaped cells, with the marginal vascular bundle embedded for most of its course.
Fossil Details
Similar Species
Recorded Fossil Sites
London Clay Formation
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