Picromerus bidens
In 3 days ~10% in a week ~30%
Picromerus bidens, the spiny shieldbug or spiked shieldbug, is a carnivorous species of shield bug in the family Pentatomidae. This species has a wide distribution in the Palaearctic, from 64°N to North Africa and from the British Isles to China. It has also been introduced, probably more than once, to North America, where it has been recorded from more than 180 sites.
These bugs prefer deciduous and mixed forests, heathland, gardens, chalk downland and damp flower-rich meadows. Picromerus bidens is a large (12 to 13.5 mm long) and distinctive predatory shieldbug. It shows a thick rostrum directed away from head. Body colour is quite variable, generally light to dark brown or bluish, with red-brown antennae and legs and two unmistakable thornlike brown projections on the sides of the pronotum (hence the species name bidens, meaning "with two teeth"). Front femurs are armed with a ventral spine distally. The early instar nymphs are commonly reddish, while the final instar nymphs are greyish black, with banded antennae and legs.
Both adults and nymphs of the spiny shieldbugs are predatory, feeding on the larvae... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Vanoise National Park | 🇫🇷 France | |
| 2 | Pyrénées National Park | 🇫🇷 France | |
| 3 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 4 | Cévennes National Park | 🇫🇷 France | |
| 5 | Wadden Sea National Park | 🇩🇪 Germany |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Helsinki | 🇫🇮 Finland | |
| 2 | Birmingham | 🇬🇧 United Kingdom | |
| 3 | Warsaw | 🇵🇱 Poland | |
| 4 | Manchester | 🇬🇧 United Kingdom | |
| 5 | Toronto | 🇨🇦 Canada | |
| 6 | Saint Petersburg | 🇷🇺 Russia | |
| 7 | Moscow | 🇷🇺 Russia |
Rare
Under 5% of wildlife watchers report a Spiny Shield Bug sighting in Warsaw on a given day, based on 7 verified sightings from GBIF citizen-science data. It is the 413th most-seen of the 580 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
September and October
In those months about 10% of wildlife watchers report a Spiny Shield Bug in Warsaw on a given day, against under 5% in November to August, the lowest months.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Spiny Shield Bug 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 7
Of the 7 cities where we can rate Spiny Shield Bug sightings, Warsaw ranks 3rd at under 5%. The best odds are in Helsinki (Finland, about 10%) and Birmingham (United Kingdom, under 5%).
Same family: Pentatomidae
The closest relatives of the Spiny Shield Bug that you can see in Warsaw (family Pentatomidae, Stink Bugs) are Green Shield Bug (about 20%), European Striped Shield Bug (about 20%) and Forest Bug (about 20%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Spiny Shield Bug is recorded against all the insects logged in Warsaw (7 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.
