Prosotas dubiosa
In 3 days ~50% in a week ~80%
Prosotas dubiosa, the tailless lineblue or small purple lineblue, is a blue butterfly (Lycaenidae) found in Asia to Australia. The species was first described by Georg Semper in 1879. Unlike many other species in the Prosotas genus, P. dubiosa does not have hair-like filaments ("tails") protruding from its hindwings, thus the tailless in its common name.
Prosotas dubiosa subardates (Piepers & Snellen, 1918) - Java, Sulawesi The butterfly occurs in Sri Lanka and peninsular India and the Himalayas from Sikkim to Assam. The range extends onto Myanmar and Yunnan, and, possibly Thailand, Peninsular Malaysia, Singapore, Hong Kong, Sumatra, Borneo and Java. Possibly Philippines and Sulawesi. Further east the butterfly occurs in Australia, New Guinea and the Solomon Islands. In Australia the butterfly occurs from Northern Australia to New South Wales (Coffs Harbour).
List of butterflies of India (Lycaenidae... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 2 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 3 | Kakadu National Park | 🇦🇺 Australia |
Possible
About 20% of wildlife watchers report a Tailless Lineblue sighting in Cuc Phuong National Park on a given day, based on 12 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 95th most-seen of the 126 insects 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.
May
In that month about 50% of wildlife watchers report a Tailless Lineblue in Cuc Phuong National Park on a given day, against under 5% in July–August and October–April, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Tailless Lineblue sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 3 parks where we can rate Tailless Lineblue sightings, Cuc Phuong National Park has the highest daily chance: about 20%. Next come Kaeng Krachan National Park (Thailand, about 10%) and Kakadu National Park (Australia, about 10%).
GBIF citizen-science records
It is estimated from how often the Tailless Lineblue is recorded against all the insects logged in Cuc Phuong National Park (12 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.
