Prosotas nora
In 3 days ~40% in a week ~70%
Prosotas nora, the common lineblue, is a species of lycaenid butterfly found in Asia to Australia. The species was first described by Rudolf Felder in 1860. Male upperside: purplish brown or purplish with a dark tint, some specimens brown with a very slight purplish sheen seen only in certain lights. Forewings and hindwings: nearly uniform, both with slender black anteciliary lines, the hindwing in addition with the costal and dorsal margins paler; in most specimens with a subterminal black spot in interspace 2, sometimes seen only by transparency from the underside; tail black tipped with white. Underside: brown, hoary, brownish or pale dull brown. Forewing: a subbasal pair of transverse white strigae, a shorter pair along the discocellulars and a discal pair; these strigae all narrowly edged on the inner sides of each pair with fuscous which gives the appearance of transverse bands somewhat darker than the ground colour; the subbasal pair extend from vein 1 to vein 12, the discocellular pair from upper to lower apex of cell and the discal pair are very irregular and dislocated at each vein, the whole having the appearance of a dark sinuous band; terminal markings... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Namdapha National Park | 🇮🇳 India | |
| 2 | Cuc Phuong National Park | 🇻🇳 Vietnam | |
| 3 | Sinharaja Forest Reserve | 🇱🇰 Sri Lanka | |
| 4 | Taroko National Park | 🇹🇼 Taiwan | |
| 5 | Taman Negara National Park | 🇲🇾 Malaysia | |
| 6 | Gunung Leuser National Park | 🇮🇩 Indonesia | |
| 7 | Kaeng Krachan National Park | 🇹🇭 Thailand | |
| 8 | Khao Yai National Park | 🇹🇭 Thailand | |
| 9 | Kinabalu Park | 🇲🇾 Malaysia |
Possible
About 20% of wildlife watchers report a Common Line Blue sighting in Sinharaja Forest Reserve on a given day, based on 10 verified sightings from GBIF citizen-science data from 2019 to 2026. It is the 47th most-seen of the 117 insects we can rate there. Over three days the chance rises to about 40%, and over a week to about 70%, if each day is a fresh chance.
March–April and November
In those months about 30% of wildlife watchers report a Common Line Blue in Sinharaja Forest Reserve on a given day, against under 5% in May–October and December–January, the lowest months.
Between 11 am and 2 pm
Across all the parks we cover, that three-hour window holds the most Common Line Blue sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
3rd of 9
Of the 9 parks where we can rate Common Line Blue sightings, Sinharaja Forest Reserve ranks 3rd at about 20%. The best odds are in Namdapha National Park (India, about 40%) and Cuc Phuong National Park (Vietnam, about 30%).
Same family: Lycaenidae
The closest relatives of the Common Line Blue that you can see in Sinharaja Forest Reserve (family Lycaenidae, Gossamer-winged Butterflies) are Angled Pierrot (about 30%), Common Cerulean (about 30%) and Red Pierrot (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Common Line Blue is recorded against all the insects logged in Sinharaja Forest Reserve (10 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.
