Its natural habitats are subtropical or tropical moist lowland forests, swamps, and intermittent freshwater marshes.

Chiasmocleis ventrimaculata is a small nocturnal frog of a snout–vent size of approximately 2 cm.

[5] These frogs prefer to remain underground during the day and emerge after dusk alongside their spider hosts and forage the surrounding areas.

This means that they will sit and wait for food to arrive, similar to ambush predators.

[7] C. ventrimaculata has several close relatives: Chiasmocleis albopunctata; C. anatipes; C. antenori; C. avilapiresae; C. bassleri; C. carvalhoi; C. devriesi; C. haddadi; C. hudsoni; C. magnova; C. papachibe; C. royi; C. shudikarensis; C. supercilialba; C.

Immediately after hatching, the frogs will remain motionless in a vertical position with their head up under the water.

[4] These tadpoles can be observed at different depths in shallow water (about 60 cm deep) and form big, nearly motionless aggregations, in which each individual is positioned in the same direction.

[8] After the first substantial rainfall (above 60 mm), males will begin to appear in nearby ponds of water and start to call.

These choruses will first begin on land within leaf litter, and later from floating leaves and twigs.

In general, reproductive activities were highest at the beginning of the rainy season and decrease rapidly after November.

[8] Males will make calls during the breeding season that consist of a series of short pulses (7–8 per second).

[7] After hatching, the tadpoles will prefer the shores of the waters and tend to aggregate there as a way to defend against aquatic predators.

[9] This frog is primarily known for its mutualistic relationship with a burrowing tarantula originally thought to be Xenesthis immanis.

[10] It has been hypothesized that the tarantulas might benefit from this relationship due to the fact these frogs are ant specialists, which can help them protect female spider's eggs from predation, increasing the fitness of female spiders who have these frogs in their burrows.

[9] The spiders did attempt to catch and eat five species of frogs from the families Bufonidae, Hylidae, and Leptodactylidae.

[10] As tadpoles, Chiasmocleis ventrimaculata are often preyed upon by freshwater crustacean species such as Dilocarcinus and Goyazana.

In addition, turtle species such as Phrynops gibbus and Podocnemis unifilis are also known to feed on tadpoles.

Even certain species of bats, suspected to be Trachops cirrhosus, have been seen trying to feed on frogs during mass mating calls.

In addition, when threatened these frogs will make a short leap and land with their legs stretched backwards in a stiff-legged posture.