Coral Bean - The red seeds of Coral Bean (Erythrina herbacea) remain nestled in their open pod. They are toxic to humans, and since they have persisted into the late Winter it seems likely that there are no animals there that eat them.
One of the most deadly plant toxins, abrin, is produced by rosary pea (Abrus precatorius). As little as of toxin per body weight will cause fatality in humans (a single seed). Birds appear to be unaffected by the deadly toxin.
I have these plants for Mike and Yuting's garden: Seed pod from Chinese lanterns. As the beautiful orange lantern decays it leaves a weblike cocoon which finally releases the seed at the right time. Evidence of design.