# Glass Frog — Facts, Threats & Conservation

*Hyalinobatrachium valerioi*

> Glass frogs are small tree frogs of Central and South American rainforests, famous for the translucent skin on their bellies that reveals their internal organs and beating heart. They are nocturnal, arboreal, and care for their eggs on leaves above streams.

**IUCN status:** Least Concern  ·  **WARN range:** North America, South America

## Quick facts
| Fact | Value |
| --- | --- |
| Scientific name | Hyalinobatrachium valerioi |
| Diet | Insectivore (small insects, spiders) |
| Habitat | Streamside vegetation in humid rainforest |
| Lifespan | About 10–14 years |
| Weight | Around 5 g (0.2 oz) |
| Size | 2–3 cm (0.8–1.2 in) body length |
| Conservation status | Least Concern (IUCN) |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Amphibia
- **Order:** Anura
- **Family:** Centrolenidae

## Conservation status
- **Status:** Least Concern (IUCN Red List category)
- **Population:** Global population not compiled for this guide
- **Trend:** See the IUCN Red List assessment
- **Assessed:** See the IUCN Red List assessment
- **CITES:** See CITES appendices
- Conservation figures are drawn from the IUCN Red List and CITES; this guide links to the authoritative sources rather than restating population counts.

## Key facts: Glass Frog
- Glass frogs are named for the translucent skin on their undersides, through which the heart, liver, and digestive tract can be seen.
- These tiny frogs are insectivores that hunt at night among leaves near streams.
- Glass frogs live in humid montane and lowland rainforests of Central and South America, almost always near clear, flowing streams.

## Behavior and transparency
Glass frogs are named for the translucent skin on their undersides, through which the heart, liver, and digestive tract can be seen. Recent research found that some glass frogs become even more transparent while sleeping by tucking red blood cells into their liver. Their green backs help them blend with leaves by day, while they are active and vocal at night.

## Diet and feeding
These tiny frogs are insectivores that hunt at night among leaves near streams. They eat small insects such as flies, crickets, and ants, as well as spiders, snatching them with a quick tongue. Their small size limits them to equally small prey.

## Habitat and range
Glass frogs live in humid montane and lowland rainforests of Central and South America, almost always near clear, flowing streams. Males often guard clutches of eggs laid on leaves overhanging the water, so that hatching tadpoles drop into the stream below. They depend on clean water and dense streamside plants.

## Conservation
Many glass frog species are listed as Least Concern, but they are highly sensitive to deforestation, water pollution, and the amphibian fungal disease chytridiomycosis. Because they need pristine streams, they are useful indicators of rainforest health. Some narrow-range species are threatened or poorly known.

## What WARN does
WARN does not run a dedicated glass frog programme — this guide is part of the World Animal Rescue Network's free educational library. The glass frog is currently widespread and not globally threatened, and this guide helps readers understand the pressures that can change that. Building public understanding of species like the glass frog supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.

## Frequently asked questions: Glass Frog
### Why are glass frogs transparent?
Glass frogs have translucent skin on their bellies that lets you see their internal organs, including the beating heart. The transparency is thought to help them blend in and avoid detection by predators.

### What do glass frogs eat?
Glass frogs are insectivores that eat small insects such as flies, crickets, and ants, along with spiders, hunting at night among streamside leaves.

### Where do glass frogs live?
They live in humid rainforests of Central and South America, almost always near clear, flowing streams where they breed on overhanging leaves.

### How big are glass frogs?
Glass frogs are very small, with most species measuring only about 2 to 3 cm (0.8 to 1.2 in) in body length.

### Do glass frogs care for their eggs?
Yes. In many species the male guards the eggs, which are laid on leaves above a stream, keeping them moist and protected until the tadpoles hatch and drop into the water.

### Are glass frogs dangerous?
Glass Frogs are not generally dangerous to people. Glass frogs are small tree frogs of Central and South American rainforests, famous for the translucent skin on their bellies that reveals their internal organs and beating heart. Give wild individuals space and do not corner or handle them.

### How long do glass frogs live?
Glass Frogs typically live About 10–14 years. Glass frogs are small tree frogs of Central and South American rainforests, famous for the translucent skin on their bellies that reveals their internal organs and beating heart. Wild and captive figures can differ; use the sources listed on the guide for the underlying studies.

## Sources
- [IUCN Red List — Hyalinobatrachium valerioi](https://www.iucnredlist.org/search?query=Hyalinobatrachium%20valerioi&searchType=species)
- [Wikipedia — Glass Frog](https://en.wikipedia.org/wiki/Hyalinobatrachium_valerioi)
- [Wikidata — Glass Frog](https://www.wikidata.org/wiki/Q905610)

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Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/glass-frog