I is for…..

Idiospermum
Idiospermum hales from the Daintree national park in Queensland, Australia. It was discovered in the late 19th century having previously only been known from their fossil record (making them what is known as a Lazarius taxon). Unfortunately the botanist that identified the plant from samples brought to him by loggers misidentified it as a Calycanthus (it is actually a member of the Calycanthaceae) When he visited the area where it had been found he saw it had been clear felled and thus the species was believed to have become extinct again! Then in 1971 it was rediscovered after some cattle grazing in the forest started to die. The poisonous seeds of the ‘Idiot plant’ where discovered in their gut.
Idiospermum actually means unusual fruit pertaining to the fact that its seed is a naked plant embryo. It is also unusual in that it can have between 2 and 5 cotyledons (seed leaves) making it neither a monocot nor dicot!
With fossils resembling Idiospermum (Virginianthus calycanthoides) aged at 120 million years and phylogenetic data placing it as one of the earliest extant (alive today) species of flowering plant. The evidence points to it being a true ‘fossilplant’.
I wish I could grow it here in North Wales but alas the garden just isn’t hot enough!