Lifted a lid on a overflow yard drain box and saw these 2 together, everyday... there is a 3 inch pipe that connects to the box out to the edge of yard, they are not stuck in there
Probably since they both hunt in different areas, and eat different things, that they can at least share a space.
It could also be their simply don't regard each other worthy of notice.
A symbiotic relationship would be if both are actively helping each other, like prawn gobies and the blind shrimp they care for, the goby guides and protects the shrimp, the shrimp digs and cares for the home of both of them. The goby cannot dig very well.
The fig wasp and fig tree are another symbiotic relationship. (Neither can survive without the other)