I spy Spilosomas

Here we go! This time with tiger moths

According to Moths of North Carolina website, there are three Spilosoma species to be found in the NC Coastal plain.

Spilosoma congrua
Spilosoma dubia
Spilosoma virginica
and BugGuide mentioned that Hyphantria cunea can be confused with the others, and moths of NC had it on the coastal plain checklist as well, so we'll look at that as well. All of the following information is taken directly from BugGuide unless otherwise mentioned.

Virginian Tiger Moth Spilosoma virginica

• wingspan 32-52 mm
• "S. virginica has yellow markings on the abdomen"- Paul Dennehy
• tibiae and tarsi will be strongly white with complete or partial black banding dorsally along the tarsi.
• Yellow egg masses

Agreeable Tiger Moth Spilosoma congrua

• wingspan 27-47 mm
• "S. congrua's abdomen is pure white" - Paul Dennehy
• tibiae and tarsi will be solid white laterally, bordered by solid black medially along the interior of the tibiae/tarsi with a clear demarcation and no banding on tarsi.
• White egg masses

Dubious Tiger Moth Spilosoma dubia

• wingspan 32-38 mm
• Yellow areas on abdomen. Black dots down dorsal abdomen- dots are larger than H. cunea's (personal observation, not from BugGuide).

Fall webworm moth Hyphantria cunea

• wingspan 25-42 mm
• has small row of dots down dorsal abdomen
• tibiae and tarsi vary – in immaculate specimens the tibiae/tarsi is often completely white/pale, while in heavily marked specimens, the tibiae/tarsi are completely black.
• In other lighter marked specimens, tarsi may appear banded and most similar to S. virginica, but will only appear so laterally with solid black/dark medially.
• When dealing with this variation, it’s typically described as H. cunea having dark tibiae/tarsi, the tarsi banded with white, verses S. virginica having mostly white tibiae/tarsi, the tarsi banded with black.
• very pale green egg masses

Posted on July 30, 2023 06:07 PM by aureleah_aurita