Tunnelled pentagonal rotunda

The  is a quasi-convex Stewart toroid. It can be made by excavating a pentagonal rotunda by a pentagonal antiprism and a pentagonal cupola.

Related polytopes
The can be elongated in two ways to form quasi-convex Stewart toroids, both with the elongated pentagonal rotunda as their convex hull. It cannot be gyroelongated.

12 tunnelled pentagonal rotundae are used in the construction of the Webb toroid.