This is a surface with interesting limits. The divisor of the squared Gauss map is below.

Below are 8 copies of a translational fundamental piece near the two limits: Two doubly periodic Karcher-Scherk surfaces of genus 0 and 2 on the left (with catenoidal stitches), and horizontal planes joined by Costa and Catenoidal nodes.

This examples indicates that Costa and Catenoid nodes can occur simultaneously, at least between different planes.

##### Resources

Mathematica Notebook

PoVRay Sources