An abnormally twinned fossil fruit of Iodes Blume (Icacinaceae) from Rivecourt (Thanetian, Oise, France)

The Rivecourt site (Thanetian from Oise, France) includes about 70 endocarp specimens distributed among five Iodes Blume species. Of the 36 specimens of Iodes rivecourtensis Del Rio, Thomas & De Franceschi one has an abnormal morphology. It is divided in two locules rather than one, and two apical apertures per face in contrast to normal specimen possessing only one per face. Icacinaceae Miers is a family with one carpel and two pendulous ovules where only one becomes mature. Here we have cases of two fused carpels, revealed by a wall between the twin lateral parts and by the four apertures, probably corresponding to the vascularisation of the four ovules. Finaly, we hypothesize that the two functional locules found here may correspond to a partial reversion of ancestral characters of the fruit.