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Catocala unijuga - female

Catocala unijuga - Female
9 miles south of Wrangell, Wrangell County, Alaska, USA
September 9, 2013
Size: 3" wingspan
This is the second Catocala that showed up at our porch light. The previous night C. unijuga came to the same light . At first I thought they were the same species, but after the photos were sent to Derek Sikes at UAM and then to several lepidopterists and finally the specimens sent to Larry Gall for id confirmation, I learned how to tell the difference. In C. semirelicta, the black median band in the hind wing doesn't make it all the way to the inner margin as it does in C. unijuga. Both of these species are found in BC which isn't that far away from Wrangell. The other similar Catocala's don't come this far west. These are the first 2 records of the genus in the state.


It's NOT semirelicta
Robert Borth, one of the lepidopterists working on the Catocala revision, sent a leg to BOLD and the DNA result shows this specimen to be Catocala unijuga. per Bob: "C. semirelicta generally has more salmon colored rather than scarlet hindwings and has more contrasty forewings with more dark around the reniform." Apparently this group of species is difficult to distinguish. While these 2 individuals are quite different, it makes more sense that only 1 new species has shown up in Alaska. Bob is also pretty certain that the fuzzy photo Matt Goff in Sitka posted is C. unijuga.