Anasa tristis
In 3 days ~10% in a week ~20%
Anasa tristis is a species of bug in the family Coreidae. It is a major pest of squash and pumpkins, found throughout North America, and is a vector of the cucurbit yellow vine disease bacterium. These bugs can emit an unpleasant odor when disturbed. It is commonly known as the squash bug but shares this name with certain other species.
The adult A. tristis is a greyish-brown, somewhat flattened insect reaching a length of about 1.5 cm (0.6 in) and a width of 0.75 cm (0.3 in). There is often a row of alternate brown and gold spots along the margin of the abdomen. Adults survive for three or four months.
Anasa tristis can be found on various members of the gourd family Cucurbitaceae, but most often occurs on pumpkins and squashes. Some varieties and cultivars are more susceptible to attack than others. Research has shown that nymphs can grow to adulthood with varying degrees of success on different host plants; 70%, 49%, 14%, 0.3% and 0% survived to maturity on pumpkin, squash, watermelon, cucumber and cantaloupe melon respectively. Nymphs can develop from the first instar to the second instar when fed on pumpkin, cucumber, or even water alone, but... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Portland | 🇺🇸 United States | |
| 2 | Salt Lake City | 🇺🇸 United States | |
| 3 | Minneapolis [Saint Paul] | 🇺🇸 United States | |
| 4 | Dallas | 🇺🇸 United States | |
| 5 | Philadelphia | 🇺🇸 United States | |
| 6 | Phoenix | 🇺🇸 United States | |
| 7 | Baltimore | 🇺🇸 United States | |
| 8 | Sacramento | 🇺🇸 United States | |
| 9 | Denver | 🇺🇸 United States | |
| 10 | Washington | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Squash Bug sighting in Chicago on a given day, based on 18 verified sightings from GBIF citizen-science data. It is the 473rd most-seen of the 978 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.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Squash Bug in Chicago on a given day, so our monthly data shows no clear season.
11th of 15
Of the 15 cities where we can rate Squash Bug sightings, Chicago ranks 11th at under 5%. The best odds are in Portland (United States, about 10%), Salt Lake City (United States, under 5%) and Minneapolis [Saint Paul] (United States, under 5%).
GBIF citizen-science records
It is estimated from how often the Squash Bug is recorded against all the insects logged in Chicago (18 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.
