Hydrophylax gracilis
Silhouette: Michael Scroggie, from original photograph by John Bettaso, USFWS (original photograph in public domain). · PhyloPic
In 3 days ~50% in a week ~80%
Hydrophylax gracilis, also known as Gravenhorst's frog, Gravenhorst's golden-backed frog, and Sri Lanka wood frog, is a species of frog in the family Ranidae. It is endemic to Sri Lanka. Hydrophylax gracilis occurs in marshes, agricultural land, grassland, and bush forests at elevations below 600 m (2,000 ft). Adult frogs are semi-arboreal and semi-aquatic, whereas the tadpoles live in stagnant waters. H. gracilis is a common species that can be threatened by loss of its wetland habitats through wetland reclamation, urbanization, and aquatic agrochemical pollution. However, it is present in many protected areas. Wikipedia →
Recording0:37
Sri Lanka · 2026
© Deshan Dewmina · iNaturalist · CC BY-NC 4.0
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Sinharaja Forest Reserve | 🇱🇰 Sri Lanka | |
| 2 | Minneriya National Park | 🇱🇰 Sri Lanka |
Possible
About 20% of wildlife watchers report a Sri Lanka wood frog sighting in Minneriya National Park on a given day, based on 15 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 8th most-seen of the 10 amphibians we can rate there. Over three days the chance rises to about 50%, and over a week to about 80%, if each day is a fresh chance.
April and October
In those months about 40% of wildlife watchers report a Sri Lanka wood frog in Minneriya National Park on a given day, against under 5% in January, March, May–July, September and November, the lowest months.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Sri Lanka wood frog sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 2
Of the 2 parks where we can rate Sri Lanka wood frog sightings, Minneriya National Park ranks 2nd at about 20%. The best odds are in Sinharaja Forest Reserve (Sri Lanka, about 30%).
Same order: Anura
The closest relatives of the Sri Lanka wood frog that you can see in Minneriya National Park (order Anura, Frogs and Toads) are Rohan's Globular Frog (about 30%), Chunam Tree Frog (about 30%) and Common Hourglass Tree Frog (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Sri Lanka wood frog is recorded against all the amphibians logged in Minneriya National Park (15 verified sightings from 2019 to 2026), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
