Iodes bilinica
Iodes bilinica
Summary
Iodes bilinica was an early Eocene member of a plant genus that still occurs in tropical regions today. It produced a one-seeded fruit with a hard endocarp that protected the seed as the fruit developed. The London Clay stones preserve both the outer fruit-wall structure and internal vascular anatomy.
Living Iodes are woody climbers, so a climbing growth habit is a reasonable comparison for the fossil lineage, but no London Clay stems or leaves are attached to these fruits and the habit of the individual fossil plant is not directly demonstrated. The preserved fruit nevertheless shows that the Iodes lineage was already established in early Eocene vegetation.
Quick Identification
Look for: a broad oval, slightly inflated Iodes stone with a sharp reticulate ridge network containing many freely ending ridgelets, plus a pronounced marginal keel. CT/sectioning should show the vascular bundle embedded in the wall and a finely papillate locule lining.
Diagnostic Features
- Endocarp is broadly oval and slightly inflated rather than strongly flattened.
- Surface has prominent acute ridges forming a reticulum with numerous freely ending ridgelets.
- A conspicuous marginal keel contains the embedded primary vascular bundle.
- Locule lining is finely papillate.
- Apex lacks the paired horn-like projections characteristic of Iodes corniculata.
Fossil Details
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
- 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
- Marjorie Elizabeth Jane Chandler. (1961). The Lower Tertiary Floras of Southern England. I. Palaeocene Floras. London Clay Flora (Supplement). . British Museum (Natural History), London View reference