Arhopala centaurus
In 3 days ~50% in a week ~80%
Arhopala centaurus, the centaur oakblue or dull oakblue, is a species of lycaenid or blue butterfly found in India and southeast Asia to the Philippines. Male. Upperside very dark blue with a violaceous tint, with black outer marginal fine border and black cilia, a rather broad black tail at the end of vein 2, a slight angular, black projection at the end of vein 1, abdominal space pale. Underside. Forewing with the basal half above the median vein dark violet-brown, the outer portion above that vein somewhat paler, the lower portion of the wing pale ochreous brown; a large round spot inside the cell near the base, a large bar in the middle, and another, larger still, at the end, very slightly darker than the ground colour, formed by their very prominent pale blue edgings, a small pale ringed spot on the costa, above the outer bar, an oblique angled spot below it on its inner side, a round spot below the middle bar, both edged with pale blue, a discal band of large conjoined more or less square spots increasing in size hindwards to vein 2, where it is joined on its inner edge to a large square spot in the next interspace, all edged on both sides with whitish; a sub... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cuc Phuong National Park | 🇻🇳 Vietnam |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Thiruvananthapuram | 🇮🇳 India | |
| 2 | Thrissur | 🇮🇳 India | |
| 3 | Kozhikode | 🇮🇳 India | |
| 4 | Denpasar | 🇮🇩 Indonesia | |
| 5 | Singapore | 🇸🇬 Singapore | |
| 6 | Kochi | 🇮🇳 India | |
| 7 | Jakarta | 🇮🇩 Indonesia | |
| 8 | Bandung | 🇮🇩 Indonesia | |
| 9 | Kuala Lumpur | 🇲🇾 Malaysia | |
| 10 | Bangkok | 🇹🇭 Thailand |
Possible
About 20% of wildlife watchers report a Dull Oak-Blue sighting in Cuc Phuong National Park on a given day, based on 9 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.
June
In that month about 60% of wildlife watchers report a Dull Oak-Blue in Cuc Phuong National Park on a given day, against under 5% in July–August and October–April, the lowest months.
Between 7 and 10 am
Across all the parks we cover, that three-hour window holds the most Dull Oak-Blue sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Only Cuc Phuong National Park, in our data
Cuc Phuong National Park is the only park on Wallace's Line with enough records to rate Dull Oak-Blue sightings: about 20% of wildlife watchers there report one on a given day.
Same family: Lycaenidae
The closest relatives of the Dull Oak-Blue that you can see in Cuc Phuong National Park (family Lycaenidae, Gossamer-winged Butterflies) are Branded Yamfly (about 30%), Common Ciliate Blue (about 30%) and Plains Cupid (about 30%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Dull Oak-Blue is recorded against all the insects logged in Cuc Phuong National Park (9 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.
