Walnut Underwing Moth in Los Angeles

July 17, 2010
We were sitting on the front porch when we saw this Underwing Moth in the genus Catocala alight on the carob tree during the afternoon.  We are uncertain what species it is.  There are many possibilities picture on BugGuide, many of which look the same to our untrained eyes.  Exactly one year ago, we posted an image of an Underwing Moth that was attracted to the porch light.

Walnut Underwing Moth

Update:  September 12, 2013
Through the years, we continue to see Underwing Moths, nearly every summer, and we now believe this is a Walnut Underwing, Catocala piatrix, which Charles Hogue writes about in Insects of the Los Angeles Basin, indicating:  “On the hottest days of summer (in July and August) adults may been seen [sic] flying during the day in the neighborhood of the larval food plant, which is the California Walnut (
Juglans californica).”  BugGuide calls this species the Penitent.

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