Curculio glandium
In 3 days ~10% in a week ~30%
Curculio glandium, commonly known as the acorn weevil, is a species of European carpophagus weevil in the genus Curculio, the acorn and nut weevils. It eats by a rostrum, an elongated snout, that is used for piercing. Curculio glandium is a member of the genus Curculio, which comprises seed beetles. All members of Curculio have characteristically long rostrums and ovipositors, an adaptation that specifically developed by their reliance on seeds for food and reproduction.
Male/female differentiation can be determined using the rostrum as the female's is longer. In female acorn weevils, their rostrums are around the size of their body or larger, while males have a rostrum around two thirds of that size. The larvae are short, and cylindrical in shape, and move by means of ridges on the underside of the body. Adults can reach a length of 4 to 8 mm (0.16 to 0.31 in).
Curculio glandium eggs are deposited in acorns by the adult weevil chewing channels into the fruit. The eggs are then released using an ovipositor, a long, narrow organ featured in female weevils. These do not reach the acorn's embryo and are healed by the plant, sealing the holes and protecting... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Bavarian Forest National Park | 🇩🇪 Germany | |
| 2 | Wadden Sea National Park | 🇩🇪 Germany | |
| 3 | Pyrénées National Park | 🇫🇷 France |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Kharkiv | 🇺🇦 Ukraine | |
| 2 | Kyiv | 🇺🇦 Ukraine | |
| 3 | Berlin | 🇩🇪 Germany | |
| 4 | Hamburg | 🇩🇪 Germany | |
| 5 | London | 🇬🇧 United Kingdom | |
| 6 | Essen | 🇩🇪 Germany | |
| 7 | Munich | 🇩🇪 Germany | |
| 8 | Birmingham | 🇬🇧 United Kingdom | |
| 9 | Copenhagen | 🇩🇰 Denmark | |
| 10 | Warsaw | 🇵🇱 Poland |
Rare
Under 5% of wildlife watchers report an Acorn Weevil sighting in Cologne on a given day, based on 5 verified sightings from GBIF citizen-science data. It is the 200th most-seen of the 235 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.
April–May and August
In those months about 10% of wildlife watchers report an Acorn Weevil in Cologne on a given day, against under 5% in June–July and September–March, the lowest months.
Between 10 am and 1 pm
Across all the parks we cover, that three-hour window holds the most Acorn Weevil sightings with a recorded time, and about half of them come between 6 am and 6 pm: it is seen both by day and at night.
12th of 15
Of the 15 cities where we can rate Acorn Weevil sightings, Cologne ranks 12th at under 5%. The best odds are in Kharkiv (Ukraine, about 10%), Kyiv (Ukraine, about 10%) and Berlin (Germany, about 10%).
Same family: Curculionidae
The closest relatives of the Acorn Weevil that you can see in Cologne (family Curculionidae, True Weevils) are Nettle Weevil (about 10%), Common Leaf Weevil (about 10%) and Green Immigrant Leaf Weevil (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Acorn Weevil is recorded against all the insects logged in Cologne (5 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.
