Why could the extinction of Elleschodes beetles threaten Eupomatia plants?

The extinction of Elleschodes beetles would threaten Eupomatia plants because these plants are dependent on beetles for pollination.31

In the genus Eupomatia, the flower structure is highly specialized to facilitate this relationship. The carpels are enclosed by a cup-shaped receptacle, leaving only their receptive stigmatic apexes exposed to the beetles that visit them. The flowers lack a traditional perianth and instead utilize petal-like staminodes to attract these insects. Because the plant relies on these specific beetles to transfer pollen to the stigmas, the loss of the pollinator would prevent the plant from successfully reproducing, as it cannot be pollinated by other means.2341