Can Dalmatian molly fish bread with guppies?

Dalmatian molly fish and guppies can breed, but the offspring may not be viable or fertile since they are different species. They belong to different genera, with mollies in the genus Poecilia and guppies also in Poecilia, but they have distinct genetic differences. While they may mate and produce hybrid fry, the success of those fry surviving and thriving is uncertain. It's generally recommended to keep them separate to maintain the integrity of each species.