Onychargia atrocyana
In 3 days ~20% in a week ~40%
Onychargia atrocyana a species of damselfly in the family Platycnemididae. This species is commonly known as the marsh dancer or black marsh dart. It is found in Asia: Bangladesh, China, Hong Kong, Indonesia, India, Sri Lanka, Myanmar, Malaysia, Philippines, Peninsular Malaysia, Singapore, Thailand, Viet Nam.
It is a medium sized damselfly with velvet-black head, thorax and black-capped brown eyes. The dorsum of the thorax has narrow citron-yellow ante humeral stripes in the sub-adult and teneral stage. The sides are citron-yellow, marked with a broad oblique black stripe over the postero-lateral suture in that stage. But all these marks are obscured by pruinescence in adults. Abdomen is black, unmarked in the adult; but with narrow bluish basal rings on segments 3 to 6. There are yellow marks on the lateral sides of segment 1 and 2 in sub-adults. Female is similar to the sub-adult male with yellow marks.
It breeds in ponds and marshes in forests. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kinabatangan Wildlife Sanctuary | 🇲🇾 Malaysia | |
| 2 | Sepilok | 🇲🇾 Malaysia | |
| 3 | Khao Yai National Park | 🇹🇭 Thailand |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Tamluk | 🇮🇳 India | |
| 2 | Kolkata | 🇮🇳 India | |
| 3 | Guwahati | 🇮🇳 India | |
| 4 | Dhaka | 🇧🇩 Bangladesh | |
| 5 | Colombo [Sri Jayawardenepura Kotte] | 🇱🇰 Sri Lanka | |
| 6 | Prayagraj | 🇮🇳 India | |
| 7 | Ho Chi Minh City | 🇻🇳 Vietnam | |
| 8 | Kochi | 🇮🇳 India | |
| 9 | Bangkok | 🇹🇭 Thailand | |
| 10 | New Delhi | 🇮🇳 India |
With luck
About 10% of wildlife watchers report a Marsh Dancer sighting in Khao Yai National Park on a given day, based on 10 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 183rd most-seen of the 221 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
May and September
In those months about 20% of wildlife watchers report a Marsh Dancer in Khao Yai National Park on a given day, against under 5% in February–March, June–August and October–December, the lowest months. Those are among Khao Yai National Park's wettest months, with about 260 mm of rain a month against 15 mm in December.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Marsh Dancer sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 3 parks where we can rate Marsh Dancer sightings, Khao Yai National Park ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Kinabatangan Wildlife Sanctuary (Malaysia, about 10%) and Sepilok (Malaysia, about 10%).
Same family: Platycnemididae
The closest relatives of the Marsh Dancer that you can see in Khao Yai National Park (family Platycnemididae, White-legged damselflies) are Yellow Featherlegs (about 20%), Black Threadtail (about 20%) and Coeliccia poungyi (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Marsh Dancer is recorded against all the insects logged in Khao Yai National Park (10 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.
