11 July 2018 - Beware the Dun-bar


Dun-bar (Cosmia trapezina)

The weather has been treacherously, dangerously dry these past two weeks and if rain doesn’t come soon plants in the garden could be in serious trouble. The moths, however, have not yet seemed to notice the looming catastrophe and are still visiting the garden in considerable numbers.

Just like the Udea olivalis, the Dun-bar (Cosmia trapezina) is not new to the garden, but has yet to be featured on the blog. This is most likely because it is a common moth and no one thought to make it a headliner before now – but finally the Dun-bar will have its day! 
The one in the photograph is a little worn - that orange bald patch is normally covered over. 

This moth is an extremely variable species, with colors ranging from earthy-yellow to dark brown. In our trap we had a greenish individual, as well as an orangey rust colored one that was rather worn. Its name is quite literal: Cosima comes from the word “kosmios” meaning well-ordered, from the attractive appearance of the species in the genus; trapezina refers to the quadrilateral shape on its forewings. The Dun-bar usually sticks to a healthy, vegetarian diet of deciduous trees –however, the moth can turn freaky fast, being known to turn cannibalistic on the larvae of other moths and even its own when in captivity.

Dun-bar [illustration]

In this photo of a drawing from Humphreys and Westwood, we can see the little heads of some caterpillars peeking up underneath the Dun-bar – not the safest spot for them considering the Dun-bar’s dark proclivities. Watch out little caterpillars!

Common Rustic (Mesapamea secalis)

We also had either a Common Rustic (Mesapamea secalis) or a Lesser Common Rustic (Mesapamea didyma); the two can only be reliably identified through dissection –and you know our feelings on that. (It turns out to be a Common Rustic...on the best authority.)

Yellow Tail (Euproctis similia)

Finally, here’s a picture of a bright and bushy Yellow Tail (Euproctis similis). This moth has been featured on the blog plenty of times before, but I can’t resist this fluffy, funny-looking little creature. 




Post by: Gabriella Morace [UPenn intern]