Castalius rosimon
In 3 days ~10% in a week ~20%
Castalius rosimon, the common Pierrot, is a small butterfly found in India that belongs to the lycaenids, or blues family. The species is found in Sri Lanka, Bangladesh, India, Myanmar; Tenasserim, extending into the Malayan subregion. In the Indonesian archipelago the butterfly occurs in north-eastern Sumatra, Kalimantan, eastern Java, Bali, Bangka, Timor, Wetar, Kissar, Sumbawa and Sulawesi.
In India the butterfly is found south of the outer ranges of the Himalayas, except in desert tracts; east India; the north-west Himalayas; Assam. The butterfly is also found in the Andaman Islands and the southern Nicobar Islands.
Forewing has the costa, apex and termen edged with black, the edging much broader on apex and termen; base outwards for a short distance more or less densely overlaid. with metallic blue scales which cover and make indistinct a large basal outwardly clavate (club-shaped) black spot; a transverse black oval spot on the discocellulars touching the black edging on the costa... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Taman Negara National Park | 🇲🇾 Malaysia | |
| 2 | Komodo National Park | 🇮🇩 Indonesia | |
| 3 | Mudumalai National Park | 🇮🇳 India | |
| 4 | Chitwan National Park | 🇳🇵 Nepal | |
| 5 | Kanha National Park | 🇮🇳 India | |
| 6 | Cat Tien National Park | 🇻🇳 Vietnam | |
| 7 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 8 | Nagarhole National Park | 🇮🇳 India | |
| 9 | Khao Yai National Park | 🇹🇭 Thailand | |
| 10 | Satpura National Park | 🇮🇳 India | |
| 11 | Doi Inthanon National Park | 🇹🇭 Thailand | |
| 12 | Minneriya National Park | 🇱🇰 Sri Lanka |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Jabalpur | 🇮🇳 India | |
| 2 | Dhaka | 🇧🇩 Bangladesh | |
| 3 | Thrissur | 🇮🇳 India | |
| 4 | Jamshedpur | 🇮🇳 India | |
| 5 | Thiruvananthapuram | 🇮🇳 India | |
| 6 | Vadodara | 🇮🇳 India | |
| 7 | Bhubaneshwar | 🇮🇳 India | |
| 8 | Chhatrapati Sambhajinagar | 🇮🇳 India | |
| 9 | Nagpur | 🇮🇳 India | |
| 10 | Surat | 🇮🇳 India |
Rare
Under 5% of wildlife watchers report a Common Pierrot sighting in Bangkok on a given day, based on 8 verified sightings from GBIF citizen-science data. It is the 186th most-seen of the 245 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
December and January
In those months about 10% of wildlife watchers report a Common Pierrot in Bangkok on a given day, against under 5% in February to November, the lowest months. Those are among Bangkok's driest months, with about 15 mm of rain a month against 280 mm in September.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Common Pierrot sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
31st of 31
Of the 31 cities where we can rate Common Pierrot sightings, Bangkok ranks 31st at under 5%. The best odds are in Jabalpur (India, about 40%), Dhaka (Bangladesh, about 40%) and Thrissur (India, about 30%).
Same family: Lycaenidae
The closest relatives of the Common Pierrot that you can see in Bangkok (family Lycaenidae, Gossamer-winged Butterflies) are Tiny Grass Blue (about 10%), Lesser Grass Blue (about 10%) and Plains Cupid (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Common Pierrot is recorded against all the insects logged in Bangkok (8 verified sightings), 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.
