Canary-shouldered Thorn – Ennomos alniaria

Night of 10th August 2018 saw a serious drop in temperature. We’ve been enjoying/sweltering in relatively balmy upper teens and into the 20s at night since May, but last night it dropped below 10 degrees Celsius in many places. The moth-ers are almost all reporting very few specimens in their traps. Personally, I had one Spectacle, a solitary Silver Y, a single Willow Beauty in the trap, and another on the white sheet hanging next to the light, and a few LBJs (Little Brown Jobs).

So here’s one of the highlights from a couple of weeks ago, a Canary-shouldered (Ennomos alniaria). It is a geometer moth (Geometridae) found across Europe. Geometers get their name from the behaviour of their larvae or caterpillars, which are whimsically also known as inchworms, their method of locomotion being reminiscent of someone measuring the earth. They’re also called loopers, for the “loop” the caterpillars form as they do their measuring.

In the UK, the adults breed in a single generation from July to September. They’re commonly found in woodland and gardens and the larvae eat the leaves of various deciduous trees. Indeed, the second part of its scientific binomial, the alniaria refers to the alder tree. The Ennominae are the largest sub-family of geometer moths, with some 9700 known species in 1100 genera.