Ctenucha brunnea
In 3 days ~10% in a week ~20%
Ctenucha brunnea, the brown ctenucha or brown-winged ctenucha, is a moth of the family Erebidae. The species was first described by Richard Harper Stretch in 1872. It is a diurnal moth found in the US from central to southern coastal California. North of that, it is replaced by Ctenucha multifaria.
Adults' bodies are 20–26 millimetres (0.79–1.02 in) in length and blue, with red heads and shoulder markings. The length of the forewings is 18–20 millimetres (0.71–0.79 in). Adults are on wing from mid May to mid July. They feed on the nectar of Heteromeles arbutifolia.
Eggs are round and fade from white to yellow, and laid in rows. The larvae are black with buff-colored or yellow hairs, with two black tufts on the front and rear and an amber or orange head. They feed on Leymus condensatus and other grasses and sedges. The pupae are chestnut in color and wrapped loosely in a cocoon of the larval hairs. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Channel Islands National Park | 🇺🇸 United States |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | San Diego | 🇺🇸 United States | |
| 2 | Los Angeles | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Brown Ctenucha sighting in San Diego on a given day, based on 16 verified sightings from GBIF citizen-science data. It is the 358th most-seen of the 693 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 Brown Ctenucha in San Diego on a given day, so our monthly data shows no clear season.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Brown Ctenucha sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
Yes
Of the 2 cities where we can rate Brown Ctenucha sightings, San Diego has the highest daily chance: under 5%. Next come Los Angeles (United States, under 5%).
Same family: Erebidae
The closest relatives of the Brown Ctenucha that you can see in San Diego (family Erebidae, Underwing, Tiger, Tussock, and Allied Moths) are Salt Marsh Moth (about 10%), Western Tussock Moth (about 10%) and Painted Tiger Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Brown Ctenucha is recorded against all the insects logged in San Diego (16 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.
