Yellow Slant Line

Subject: I this a female Imperial Moth?
Location: Sheboygan, WI
July 4, 2017 8:30 am
I found this moth attached to the siding on our porch in Sheboygan, WI. I have never seen anything like it before. It was about 1 1/2 inches from wing tip to wing tip. The stripe is definitely black, not brown. All of the information I found about Imperial Moths suggest that they are yellow with brown. What is this? Thanks!
Signature: Mary

Yellow Slant Line

Dear Mary,
This very lovely Geometer Moth is not a female Imperial Moth, though both are yellow.  We will be searching BugGuide for its identity, but in the meantime, we are posting it as unidentified.

Hello again Mary,
We identified your Geometer Moth as a Yellow Slant Line, Tetracis crocallata, thanks to images on Moth Photographers Group, and we verified its identity on BugGuide.  According to BugGuide:  “Larvae feed on leaves of alder, chestnut, sumac, willow” and “Larva – a twig mimic; young instars have brown head and green body with white intersegmental membranes; older instars have two morphs: (A) reddish-brown with 2 pairs dorsal and 2-3 pairs lateral white tubercles; T1 with forward projections tipped white (B) light brown to gray with no white tubercles; T1 projections present, but not white; morph B is similar to A. pampinaria but has no dorsal tubercles on A7 [adapted from description by Pedro Barbosa].”

Wow! Thanks, Daniel! I wonder how this poor thing ended up in Wisconsin.
I really appreciate your assistance.
Just an FYI, I left it alone. I am not in the habit of killing creatures of any sort.

Dear Mary,
Based on BugGuide data, Wisconsin has reported sightings of the Yellow Slant Line during the months May through August.

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