Bug FAQOne-eyed Sphinx
Smerinthus cerisyi · Order: Lepidoptera · Family: Sphingidae
Also called: willow sphinx, Cerisy's sphinx moth, One-eyed Sphinx Moth
Source: Wikipedia
Adults have a wingspan of about 6 to 9 cm and show a blue eyespot with a black centre on the hindwing. They are found across much of Canada and the northern United States, from Alaska and the west coast to the Rocky Mountains and into the Midwest. One generation emerges each summer and can be seen throughout the season.
Source: Wikipedia
How to recognize it
The hindwing bears a distinctive blue eyespot surrounded by a black centre.
Source: Wikipedia
Size
The moth’s wingspan ranges from 60 to 90 mm.
Source: Wikipedia
What it eats
Larvae feed on the leaves of willow, poplar, pear, plum and snowberry plants.
Source: Wikipedia
Life cycle
The species has one generation per year, with adults present for much of the summer.
Source: Wikipedia
When you see it
Adults can be seen throughout the summer months.
Source: Wikipedia
Where it comes from
It is native to North America, occurring throughout much of Canada and the northern United States.
Source: Wikipedia
Where it is found in the US
Recorded in 29 of 51 states and DC. Most records: California, Washington, Colorado, Montana, Oregon, Minnesota, Michigan, Wyoming.
Darker = more records. Counts are museum and citizen-science records, not population size.
Source: GBIF
Status: native in North America; native in Canada. Source: iNaturalist
Months it is reported in the US
Source: GBIF
More photos
Questions people ask
What plants do the caterpillars eat?
They feed on willow, poplar, pear, plum and snowberry leaves.
Source: Wikipedia
When can I see adult One-eyed Sphinx moths?
Adults are active during the summer season.
Source: Wikipedia
Same family (Sphingidae)
White-lined SphinxHyles lineataDamages trees, gardens or crops
Eurasian Hummingbird HawkmothMacroglossum stellatarum
Snowberry ClearwingHemaris diffinis
Carolina SphinxManduca sextaDamages trees, gardens or crops
Hummingbird ClearwingHemaris thysbeDamages trees, gardens or crops
Elephant HawkmothDeilephila elpenorSources
- Wikipedia: https://en.wikipedia.org/wiki/Smerinthus_cerisyi
Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia
Text written 2026-10-23 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-23.