Spiny Hook-tip

Spiny Hook-tip Watsonalla uncinula

This species has been recently discovered in the Channel Islands and now in parts of England, especially between Gloucestershire/Somerset and the Home Counties. As of 2026 it has not yet been found in Norfolk. Most of the differences between this species and Oak Hook-tip Watsonalla binaria are inconsistent, so identification based on external characters is not always possible.

I spent a night in North Somerset and trapped hoping to find this species. I arrived late so didn't put the trap out until 9.30pm but the very first moth in was a promising candidate. By dawn I had caught four examples that I suspected were Spiny Hook-tip. Two of them (subsequently turning out to be both male and female) were much larger than any Oak Hook-tip I've ever seen. These also had a distinct hoary-grey sheen to them, although this was not particularly obvious from the photos. The other two didn't stand out so much but elements of the wing-tip pattern led me to suspect they were all Spiny Hook-tip. I ran photos past the ObsIdentify app and depending on the photo used this varied from favouring Spiny Hook-tip to being 100% sure they were Oak Hook-tip. Dissecting the genitalia confirmed that none of the four (three males and a female) were Oak Hook-tips and all were consistent with Spiny Hook-tip.

One should also be careful to eliminate the not dissimilar Barred Hook-tip Watsonalla cultraria. The genitalia of that species seems to be more similar to Spiny Hook-tip than either are to Oak Hook-tip, indeed I am not completely sure I understand the differences. For my four though, I think the external appearance is sufficient to eliminate Barred.

female Spiny Hook-tip Watsonalla uncinula showing apex of wing, genitalia, close-up of ovipositor to ostium and close-up of top of ductus bursae, Cowslip Green (North Somerset, UK), 9th October 2026