Phasis thero
In 3 days ~20% in a week ~40%
Phasis thero, the silver arrowhead or hooked copper, is a butterfly of the family Lycaenidae. It is found in South Africa. The wingspan is 31–46 mm for males and 38–47 mm females. Adults of subspecies P. t. thero are on wing from September to November and again from March to May in two generations. Adults of subspecies P. t. cedarbergae are on wing from October to November and probably also in autumn.
The larvae feed on Rhus undulata and Melianthus major. Larvae have been found inside hollow stems of their food plant, but also in nests of Crematogaster peringueyi ants at the base of these stems. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | De Hoop Nature Reserve | 🇿🇦 South Africa | |
| 2 | West Coast National Park | 🇿🇦 South Africa | |
| 3 | Garden Route National Park | 🇿🇦 South Africa | |
| 4 | Table Mountain National Park | 🇿🇦 South Africa |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Cape Town | 🇿🇦 South Africa |
With luck
About 10% of wildlife watchers report a Silver Arrowhead sighting in Cape Town on a given day, based on 52 verified sightings from GBIF citizen-science data. It is the 81st most-seen of the 311 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 40%, if each day is a fresh chance.
October
In that month about 20% of wildlife watchers report a Silver Arrowhead in Cape Town on a given day, against under 5% in December to August, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Silver Arrowhead 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 Cape Town, in our data
Cape Town is the only city on Wallace's Line with enough records to rate Silver Arrowhead sightings: about 10% of wildlife watchers there report one on a given day.
Same family: Lycaenidae
The closest relatives of the Silver Arrowhead that you can see in Cape Town (family Lycaenidae, Gossamer-winged Butterflies) are African Grass Blue (about 20%), Geranium Bronze (about 10%) and Water Geranium Bronze (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Silver Arrowhead is recorded against all the insects logged in Cape Town (52 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.
