Eucryptorrhynchus brandti
In 3 days ~20% in a week ~40%
Eucryptorrhynchus brandti, the Ailanthus trunk weevil or snout weevil, is an insect in the weevil family. In its native range in China, it causes significant damage to its single host, Ailanthus altissima, tree of heaven. Thus the weevil is under study as a biological control of tree of heaven in regions where the tree is non-native. In particular, the insect acts as a vector for Verticillium nonalfalfae, a soilborne fungus that causes verticillium wilt.
Eucryptorrhynchus brandti produces one generation per year, with larvae and adults overwintering. Adult weevils feed on leaves, buds, and petioles. Larvae develop under the bark of the host plant, boring and feeding, to emerge as adults through round emergence holes 4 millimeters in diameter. Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Eucryptorrhynchus brandti sighting in Nanjing on a given day, based on 10 verified sightings from GBIF citizen-science data. It is the 150th most-seen of the 272 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, June and August–September
In those months about 10% of wildlife watchers report a Eucryptorrhynchus brandti in Nanjing on a given day, against under 5% in May, July and October–February, the lowest months.
Among the best
Of the 3 cities where we can rate Eucryptorrhynchus brandti sightings, Nanjing ranks 3rd at about 10%, level with the leaders once rounded. The best odds are in Beijing (China, about 10%) and Qingdao (China, about 10%).
GBIF citizen-science records
It is estimated from how often the Eucryptorrhynchus brandti is recorded against all the insects logged in Nanjing (10 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.
