Nacaduba biocellata
In 3 days ~10% in a week ~20%
Nacaduba biocellata, the double-spotted line blue, is a butterfly of the family Lycaenidae. It is found in Australia (including New South Wales, the Northern Territory, South Australia, Victoria and Western Australia), Singapore, the New Hebrides, Sumba and Bali.
The wingspan is about 20 mm. Adult females have a brown upperside, while the males are blue with narrow black margins. The underside of both sexes is pale brown with light and dark wavy lines. The larvae feed on the shoots, flowers and buds of various Acacia species, including A. aneura, A. betchei, A. brachybotrya, A. deanei, A. erinaceae, A. irrorata, A. karroo, A. ligulata, A. osswaldii, A. penninervis, A. rigens, A. salicina, A. sclerophylla, A. sowdenii and A. victoriae. They can have a wide range of colours depending on their host plant, including pink, orange, yellow or green. They are attended by ants, mostly Iridomyrmex species, including I. purpureus and I. viridiaeneus.
Pupation takes place in a pale brown pupa. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Uluru-Kata Tjuta National Park | 🇦🇺 Australia | |
| 2 | Flinders Ranges National Park | 🇦🇺 Australia | |
| 3 | Hattah-Kulkyne National Park | 🇦🇺 Australia | |
| 4 | Ningaloo Marine Park | 🇦🇺 Australia |
Rare
Under 5% of wildlife watchers report a Double-Spotted Line Blue sighting in Singapore on a given day, based on 29 verified sightings from GBIF citizen-science data. It is the 589th most-seen of the 1045 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.
January
In that month about 10% of wildlife watchers report a Double-Spotted Line Blue in Singapore on a given day, against under 5% in February to December, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Double-Spotted Line 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.
3rd of 5
Of the 5 cities where we can rate Double-Spotted Line Blue sightings, Singapore ranks 3rd at under 5%. The best odds are in Perth (Australia, about 10%) and Melbourne (Australia, about 10%).
Same genus: Nacaduba
The closest relatives of the Double-Spotted Line Blue that you can see in Singapore (genus Nacaduba) are Rounded Sixline Blue (about 10%), Transparent 6-Line Blue (about 10%) and Large Fourline Blue (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Double-Spotted Line Blue is recorded against all the insects logged in Singapore (29 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.
