Arrenodes minutus
In 3 days ~10% in a week ~20%
Arrenodes is a genus of primitive weevils belonging to the family Brentidae, containing a single described species, Arrenodes minutus, commonly known as the oak timberworm. These beetles are pests of hardwoods in North America. Adult oak timberworms are shiny, elongate, and range 7 to 25 mm in length. They are reddish-brown to brownish-black in coloration, with yellow spots on their elytra. Adults display strong sexual dimorphism; females have long, slender, straight mouthparts, while males possess flattened, broadened mouthparts with large mandibles. Males are known to be aggressive and use these large mandibles for combat. These mandibles are also used in courtship. Larvae are elongate, cylindrical, white, and curved. They have three pairs of jointed legs on the thorax and one pair of prolegs near the end of the abdomen.
Oak timberworms primarily attack oak (Quercus spp.), elm (Ulmus spp.), beech (Fagus spp.), and Populus species such as aspen and poplar. They have also been documented on boxelder (Acer negundo) and honeylocust (Gleditsia triacanthos). Upland oak species such as black oak (Q. velutina) and scarlet oak (Q. coccinea) appear to be especially susceptible... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Shenandoah National Park | 🇺🇸 United States | |
| 2 | Great Smoky Mountains National Park | 🇺🇸 United States |
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Baltimore | 🇺🇸 United States | |
| 2 | Washington | 🇺🇸 United States | |
| 3 | Boston | 🇺🇸 United States | |
| 4 | Toronto | 🇨🇦 Canada | |
| 5 | New York City | 🇺🇸 United States | |
| 6 | Chicago | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report an Oak Timberworm sighting in Baltimore on a given day, based on 6 verified sightings from GBIF citizen-science data. It is the 546th most-seen of the 705 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
May
In that month about 10% of wildlife watchers report an Oak Timberworm in Baltimore on a given day, against under 5% in June to April, the lowest months.
Between noon and 3 pm
Across all the parks we cover, that three-hour window holds the most Oak Timberworm sightings with a recorded time, and about 7 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 6 cities where we can rate Oak Timberworm sightings, Baltimore has the highest daily chance: under 5%. Next come Washington (United States, under 5%) and Boston (United States, under 5%).
Same order: Coleoptera
The closest relatives of the Oak Timberworm that you can see in Baltimore (order Coleoptera, Beetles) are Asian Lady Beetle (about 30%), Common Green June Beetle (about 10%) and Horned Passalus Beetle (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Oak Timberworm is recorded against all the insects logged in Baltimore (6 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.
