Ctenolepisma lineata
In 3 days ~20% in a week ~30%
Ctenolepisma lineatum, the four-lined silverfish, is a species of silverfish of the order Zygentoma. It is rather stouter and less shiny with all the appendages (antennae and 3 "tails") being noticeably longer. The abdomen is often marked with dark brown lines.
This species is native to southern Europe but is now found throughout most of the world, aside from polar and cooler temperate regions (e.g. the British Isles), as an accidental introduction. It is found both indoors and outdoors and can be a nuisance pest.
Recent studies on this species in Europe suggest that, due to speciation, there is enough geographical variation to justify splitting into several species, with one form already having been given specific status as Ctenolepisma almeriense from south-eastern Spain. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Acadia National Park | 🇺🇸 United States |
More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Four-Lined Silverfish sighting in Portland on a given day, based on 46 verified sightings from GBIF citizen-science data. It is the 128th most-seen of the 507 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 30%, if each day is a fresh chance.
January–March, May, July–August and October–November
In those months about 10% of wildlife watchers report a Four-Lined Silverfish in Portland on a given day, against under 5% in April, June, September and December, the lowest months.
Between 8 and 11 pm
Across all the parks we cover, that three-hour window holds the most Four-Lined Silverfish sightings with a recorded time, and about 8 in 10 of them come between 6 pm and 6 am: it is mostly seen at night.
Among the best
Of the 29 cities where we can rate Four-Lined Silverfish sightings, Portland ranks 11th at about 10%, level with the leaders once rounded. The best odds are in Kharkiv (Ukraine, about 10%), Kyiv (Ukraine, about 10%) and Turin (Italy, about 10%).
GBIF citizen-science records
It is estimated from how often the Four-Lined Silverfish is recorded against all the insects logged in Portland (46 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.
