Four species - "H. bombycinus", "H. crucibracteatus", "H. giffardianus", and "H. wilderianus" - were only ever known from a single individual in the wild.
Четыре вида — "Hibiscadelphus bombycinus", "Hibiscadelphus crucibracteatus", "Hibiscadelphus giffardianus" и "Hibiscadelphus wilderianus" — стали известными науке благодаря единственным экземплярам, встретившимся в дикой природе.