Thrasops occidentalis is characterized by its predominantly black coloration, which provides camouflage in its natural habitat.

The diet of Thrasops occidentalis primarily consists of small mammals, birds, and occasionally reptiles.

The breeding season and specific reproductive behaviors are not well-documented but are presumed to be similar to other colubrid snakes, with females laying clutches of eggs that hatch after an incubation period.

As with many snake species, Thrasops occidentalis faces predation from larger mammals, birds of prey, and humans.

Habitat destruction and fragmentation pose significant threats to its population due to deforestation and agricultural expansion.