Byasa alcinous
In 3 days ~20% in a week ~50%
Byasa alcinous, the Chinese windmill, is a butterfly of the family Papilionidae. Byasa alcinous has a wingspan reaching about 9–10 centimetres (3.5–3.9 in). The basic colour of the wings is black or dark brown. The hindwings have long tails and a chain of red spots at the edges. The thorax and the abdomen are mainly black on the upperside and the underside, with several black spots, while the other areas are red.
Adults are on wing from May to August in two generations. The larvae feed on Aristolochia species including A. mandshhuriensis, A. debilis and A. manchuriensis. Subspecies has been recorded on A. shimadai, A. liukiuensis, A. kankauensis, A. elegans, A. debilis, A. kaempferii, A. onoei, A. tagala, Cocculus trilobus and Metaplexis chinensis. The species overwinters as a pupa.
This species can be found in the Asian part of the Palaearctic realm and partially in the Indomalayan realm, from Bhutan, and eastern China to the southern Ussuri region, Korea and Japan. Byasa alcinous is present in mixed broadleaved forests. Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Chinese Windmill sighting in Tokyo on a given day, based on 218 verified sightings from GBIF citizen-science data. It is the 76th most-seen of the 1013 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 50%, if each day is a fresh chance.
April to October
In those months about 10% of wildlife watchers report a Chinese Windmill in Tokyo on a given day, against under 5% in November to March, the lowest months.
3rd of 5
Of the 5 cities where we can rate Chinese Windmill sightings, Tokyo ranks 3rd at about 10%. The best odds are in Nagoya (Japan, about 20%) and Naha (Japan, about 10%).
Same family: Papilionidae
The closest relatives of the Chinese Windmill that you can see in Tokyo (family Papilionidae, Swallowtails and Parnassians) are Chinese Yellow Swallowtail (about 20%), Common Bluebottle (about 20%) and Old World Swallowtail (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Chinese Windmill is recorded against all the insects logged in Tokyo (218 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.
