Amphibians · Anura · Centrolenidae

Fleischmann's Glass Frog

Hyalinobatrachium fleischmanni

Least Concern

The species is abundant and widely distributed; it faces no significant short-term risk. See full glossary

Fleischmann's glass frog has a completely transparent belly: through the skin you can see the beating heart, the liver and the intestines. It lives on leaves overhanging streams and the male guards the eggs for weeks. In 2022 it was discovered how it manages to become almost invisible while it sleeps.

Size

2 cm – 3 cm

Lifespan

5 years

Diet

Insectivore

Feeds mainly on insects and other invertebrates.

Activity

Nocturnal

Active mainly at night.

Social structure

Solitary

Lives and hunts alone, joining others only to breed.

Sighting difficulty

Easy

RainforestFreshwaterInsectivore Nocturnal Solitary Amphibian Rainforest Freshwater

11countries 45parks

Fun facts

It turns transparent to sleep: a 2022 study revealed that while asleep it concentrates almost all its red blood cells in the liver, taking them out of circulation, which makes it two to three times more transparent. On waking it releases them again.
That mechanism ought to give it fatal clots and does not: how it stores so much concentrated blood without clotting is a puzzle being investigated for its possible medical applications.
The male guards the eggs, stuck to the underside of a leaf over the stream, for weeks, keeping them moist and defending them from parasitic wasps, and on hatching the tadpoles drop straight into the water.

Life cycle & biology

Skeleton type: Vertebrate - internal bony skeleton (amphibian)
Habitat & environment: Vegetation over streams in rainforest of Central America and northern South America
Sexual maturity: 12 months
Gestation / incubation: 15 days of egg development on leaves
Litter / clutch size: 30 eggs

Sources consulted: https://es.wikipedia.org/wiki/Hyalinobatrachium_fleischmanni