Southern Grey Tortrix Cnephasia communana

Formerly given the vernacular name May Shade.

Usually the first of the Cnephasia to come out, but while the date and the large size might be a strong clue, dissection is really needed to be certain of the ID, especially once Common Grey Tortrix Cnephasia stephensiana has started to fly.

This species is currently scarce in Norfolk but seems to have increased recently.

I'm yet to catch one in Norfolk but these three were caught together in Surrey (VC17) while I was visiting friends. The comparison images at the Moth Dissection website point to the long bulbous colliculum. I dont know if this is normally the case, but on this individual the colliculum was strongly bent into an S shape (best seen in side view) which meant that from the top it was not as long as it would be if this were straightened out (although even so it is still quite different from stephensiana). The sterigma shape was more like that of asseclana (shallower than stephensiana) though less tapered at the sides and a rounder ostium.

female Southern Grey Tortrix Cnephasia communana showing genitalia before and after setting, Riddlesdown (Surrey, UK), 30th May 2025

Judging from the images at the Moth Dissection website there is some variation in the length of the sacculus in males. The aedeagus is distinctively long and straight.

male Southern Grey Tortrix Cnephasia communana showing genitalia before and after setting, Riddlesdown (Surrey, UK), 30th May 2025

These three individuals were all quite similar to one another externally. I examined this one's genitalia too.

second male Southern Grey Tortrix Cnephasia communana, Riddlesdown (Surrey, UK), 30th May 2025