Microhyla heymonsi
Silhouette: Vijay Karthick · PhyloPic
In 3 days ~50% in a week ~80%
Microhyla heymonsi, also known as the dark-sided chorus frog or the Taiwan rice frog, is a species of narrow-mouthed frog found in northeastern India, southern China, Taiwan, and Southeast Asia south to the Malay Peninsula and Sumatra as well as the Great Nicobar Island. It was originally described from Taiwan.
As microhylids in general, Microhyla heymonsi is a small frog: males reach 16–21 mm (0.6–0.8 in) and females 22–26 mm (0.9–1.0 in) in snout-vent length. The dorsal colour is pinkish or greyish above with a black lateral band extending from the snout tip to the groin and entirely covering the sides of the head. It inhabits a variety of disturbed areas as well as secondary vegetation. It breeds in temporary rain puddles, paddy fields, ditches, marshes and slow-flowing streams. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 2 | Cat Tien National Park | 🇻🇳 Vietnam | |
| 3 | Doi Inthanon National Park | 🇹🇭 Thailand | |
| 4 | Khao Yai National Park | 🇹🇭 Thailand | |
| 5 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 6 | Khao Sok National Park | 🇹🇭 Thailand |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Nanjing | 🇨🇳 China | |
| 2 | Hangzhou | 🇨🇳 China | |
| 3 | Kuala Lumpur | 🇲🇾 Malaysia | |
| 4 | Bangkok | 🇹🇭 Thailand | |
| 5 | Singapore | 🇸🇬 Singapore |
Possible
About 20% of wildlife watchers report an Arcuate-spotted Pygmy Frog sighting in Cat Tien National Park on a given day, based on 18 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 12th most-seen of the 21 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.
June
In that month about 40% of wildlife watchers report an Arcuate-spotted Pygmy Frog in Cat Tien National Park on a given day, against under 5% in July to February, the lowest months. That is one of Cat Tien National Park's wettest months, with about 340 mm of rain against 15 mm in February.
Between 1 and 4 pm
Across all the parks we cover, that three-hour window holds the most Arcuate-spotted Pygmy Frog sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
2nd of 6
Of the 6 parks where we can rate Arcuate-spotted Pygmy Frog sightings, Cat Tien National Park ranks 2nd at about 20%. The best odds are in Cuc Phuong National Park (Vietnam, about 40%).
Same genus: Microhyla
The closest relatives of the Arcuate-spotted Pygmy Frog that you can see in Cat Tien National Park (genus Microhyla, Rice Frogs) are Mukhlesur's Narrow-mouthed Frog (about 40%), Ninh Thuan Narrow-mouth Frog (about 20%) and Butler's Ricefrog (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Arcuate-spotted Pygmy Frog is recorded against all the amphibians logged in Cat Tien National Park (18 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.
