Psyllobora vigintimaculata
In 3 days ~20% in a week ~40%
Psyllobora vigintimaculata, the twenty-spotted lady beetle, is a species of lady beetle in the family Coccinellidae. It is found in North America, where it has been recorded from Newfoundland to Alaska in the north and from Virginia to Tennessee and Louisiana, west to southern California.
P. vigintimaculata is about 1.75–3.0 mm in length, lives 1-2 years, and has four or five distinctive dark spots on the pronotum in an "M" shape. The elytra have dark, orange or bicolored spots on a white background. Although it is sometimes confused with the fourteen-spotted lady beetle (Propylea quatuordecimpunctata) and the Asian lady beetle (Harmonia axyridis), its unique pattern helps to distinguish it from other lady beetle species found in North America.
In a laboratory setting, the subspecies P. vigintimaculata taedata undergoes four larval instars, molting and then pupation. The timing of life cycle varies according to rearing conditions. The first instar larvae has a white oval body with small hairs projecting from the thorax. The larvae of the second instar have a stripe and a much darker color that gradually turns lighter with... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Great Smoky Mountains National Park | 🇺🇸 United States | |
| 2 | Shenandoah National Park | 🇺🇸 United States | |
| 3 | Channel Islands National Park | 🇺🇸 United States | |
| 4 | Olympic National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Portland | 🇺🇸 United States | |
| 2 | Vancouver | 🇨🇦 Canada | |
| 3 | Boston | 🇺🇸 United States | |
| 4 | Zhuhai [Macau] | 🇨🇳 China | |
| 5 | Seattle | 🇺🇸 United States | |
| 6 | San Francisco | 🇺🇸 United States | |
| 7 | Toronto | 🇨🇦 Canada | |
| 8 | Edmonton | 🇨🇦 Canada | |
| 9 | Montreal | 🇨🇦 Canada | |
| 10 | Washington | 🇺🇸 United States |
With luck
About 10% of wildlife watchers report a Twenty-Spotted Lady Beetle sighting in San Francisco on a given day, based on 478 verified sightings from GBIF citizen-science data. It is the 55th most-seen of the 737 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.
March–April and June–November
In those months about 10% of wildlife watchers report a Twenty-Spotted Lady Beetle in San Francisco on a given day, against under 5% in May and December–February, the lowest months.
Between 9 am and noon
Across all the parks we cover, that three-hour window holds the most Twenty-Spotted Lady Beetle sightings with a recorded time, and about 8 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Among the best
Of the 28 cities where we can rate Twenty-Spotted Lady Beetle sightings, San Francisco ranks 6th at about 10%, level with the leaders once rounded. The best odds are in Portland (United States, about 10%), Vancouver (Canada, about 10%) and Boston (United States, about 10%).
GBIF citizen-science records
It is estimated from how often the Twenty-Spotted Lady Beetle is recorded against all the insects logged in San Francisco (478 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.
