Subject:  Green Worm?
Geographic location of the bug:  Spokane, WA
Date: 08/14/2021
Time: 02:11 PM EDT
Your letter to the bugman:  found this little guy hiding in the lower crevice underneath my sliding door to the backyard. small enough to fit under the door entirely. i couldn’t see any legs and it seems to only move by flexing its body like a worm. thicker (and greener) than a worm, however. reacted a little to simply blowing in it but it didn’t react when i tapped it with a toothpick (not the sharp sides, i don’t wanna hurt it). no bigger than my index finger in length
How you want your letter signed:  Connor S.

One Eyed Sphinx Caterpillar

Dear Connor,
This is not a Worm.  It is a Caterpillar, more specifically a Hornworm, a caterpillar of a Sphinx Moth or Hawkmoth in the family Sphingidae.  Now comes the interesting part.  It sure looks like the caterpillar of a Lime Hawkmoth,
Mimas tiliae, but that is a European species that is pictured on Wildlife Insight.  12 years ago we posted a sighting of a Lime Hawkmoth in Pennsylvania and through that posting we learned that Lime Hawkmoths have already been reported in eastern Canada.  Doug Yanega, an entomologist at UC Riverside informed us:  “The Lime Hawkmoth is already known from eastern canada so Pennsylvania is just the first time it has been sighted across the US border. Probably introduced carelessly or intentionally from someone who has imported and was rearing Sphinx Moths from overseas.”  According to iNaturalist:  ” the lime hawk-moth, is a moth of the family Sphingidae. It is found throughout the Palearctic region and the Near East, and has also been identified in eastern Canada and in northern Spain (Europe).”  Twelve years have passed since that posting and it is entirely possible that the Lime Hawkmoth has either expanded its North American range across the continent or that it hitched across the country with tourists.  We might be wrong in our identification.  Perhaps Dr. Bostjan Dvorak or another specialist in the family Sphingidae will either confirm or correct our tentative identification.  If we are correct, this might be a first sighting in Washington as we are unable to locate any information on its presence there.

Update:  August 22, 2021
Thanks to a comment from Bostjan Dvorak, we have been informed that this is a One Eyed Sphinx Caterpillar, not a Lime Hawkmoth Caterpillar.

Tagged with →  
Location: Spokane, Washington

8 Responses to One Eyed Sphinx Caterpillar, NOT Lime Hawkmoth Caterpillar in Washington State???

  1. Colleen Smith says:

    I found one today in my backyard in Morton, WA. 8/15/2021

  2. Sprig says:

    I found one just yesterday in Washington too! I was sitting under a willow tree when I heard a plop and saw it on the ground. Now I wish I took a better picture of it…

  3. Dr. Bostjan Dvorak says:

    Dear Bugman, dear Connor, dear Colleen, dear Sprig,

    Thank You very much for sharing this fascinating observation and all the information about similar findings, on this great site! – Whatsthatbug has essentially contributed and greatly contributes to the knowledge about autochthonous and introduced insect species.
    The Lime Hawkmoth (Mimas tiliae) has indeed been reported from several places of the northern New World as an introduced species in the last decennies, mainly from a few cities in USA and Canada; as many imported organisms, it is most likely to be found in rather urban biotopes – which can also be assumed for its homeland, where it preferably follows avenues planted with lime trees within urban centres (as a synanthropic species), a tendency observed in the last centuries in European cities (eg. Berlin) – besides its natural occurrence in “undisturbed” landscapes.
    The caterpillar on the photo shows quite some similarity with that of the Lime Hawkmoth indeed (the water green ground color, the lateral stripes and the bluish horn); however, in the genus Mimas, the rear end of the caterpillar is marked by a characteristic group of prominent colorful tubercles (as on my added photo of a larva found on Potsdamer Platz in Berlin some years ago), which are missing in this individual (smooth anal part); additionally, this caterpillar’s white pattern is adorned with two straight dorso-lateral lines – completely missing in Mimas as well, but typically occurring in caterpillars of the Nearctic branch of the genus Smerinthus – indicating that the caterpillar in question belongs to that genus; as the palaearctic species Smerinthus ocellata (European One-Eyed Sphinx) lacks those lines, and these are less intensive in the eastern nearctic species, the photo shows an individual of Smerinthus ophthalmica, the Western One-Eyed Sphinx (on its pupating march, with the colors already changed). This also correlates with the information about records on willow trees (Salix) in Washington. – Pupating Mimas tiliae larvae are of a rather greyish (ventrally rosy) base color, much smaller (contracted) and strongly rounded – and very difficult to see on paved (asphalted) ground…

    Thus, the bluish-green caterpillar on the photo is of the Western One-Eyed Sphinx, Smerinthus ophthalmica. It is part of the rich natural fauna of Your region – together with other species from 4 authochthone genera of the Smerinthinae tribe – Smerinthus, Paonias, Amorpha and Pachysphinx – from which the last three are only represented in the New World, whereas Mimas was originally only represented in the Old World…

    Best regards over the sea,
    Bostjan

    • bugman says:

      Thanks for your extensive comment Bostjan. We will update the posting.

    • Kristina Paylor says:

      I found one on my corkscrew willow last week; I live near the Southworth Ferry Dock, Port Orchard, WA. I have a good close-up photo 3-4 minute video but not sure how/where to post it.

  4. bekki cox says:

    Burlington, wa. Found one yesterday. Trying to find put when they start to change? This one likes to tunnel into the ground. Actually found it underground.

  5. G. Bell says:

    Found one crawling on my shoulder after mowing under our willows. Anacortes Wa 10/22/21. Never seen one before this. Have pictures available.

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