4 July 2016 - National Moth Scheme

Dave Chesmore identifying moths

“If you don’t like the weather, wait five minutes.” So I was told by Dave Chesmore, who kindly showed up on National Garden Scheme Day to help us identify moths caught the previous night. It was a perfect description of the schizophrenic shuffle between pouring rain and blinding sun we have been getting. We had decided to set two traps instead of one to ensure the best variety and number. During one of the longer sunny spells, some twenty people hovered around the trap to see what we had managed to attract.

Figure of 80 (Tethea ocularis octogesimea)

A total of 26 species were identified and passed around the group. Beautiful and Plain Golden Y, Heart and Dart, Buff Ermine, Marbled Minor, Middle-barred Minor, and Silver-ground Carpet came in multiples. Just starting to pick up in numbers – Large yellow-underwing, Garden Grass Veneer, Light Emerald, and Common Wave. And the rest of our showstoppers – Barred Straw, Snout, Brimstone Moth, Silver Y, Small Fanfoot, Peppered Moth, Willow Beauty, Buff Arches, Flame, Common Swift, Burnished Brass, Figure of Eighty, and Flame Shoulder. A Ghost Moth was found in the tent over our trap in the top garden that morning but did not stay long enough to meet the crowd’s gaze.

The Figure of Eighty (Tethea ocularis octogesimea) is one of the moths that I remember from my first look at the Lewington illustrated field guide. Everything about this moth (except perhaps the photograph above which I took of the markings - at the worst possible angle) seems to be in service of the ‘80’: the subdued sepia ground color, the central cross-lines that sandwich the number, the scientific name octogesimus meaning ‘eightieth’, and the cylindrical resting position, all point to the figure in white. It is described as having a rosy tint, which is much faded in our sample.

Willow Beauty (Peribatodes rhomboidaria)

A pageant is brought on by our two Beauties. The Mottled Beauty (Alcis repandata) is new to me and makes a good comparison to the Willow Beauty (Peribatodes rhomboidaria), which has an outer cross-line that is more zigzag toward the leading edge and splits into tiny dots on each vein. The Mottled Beauty, in contrast, has a smoother outer cross-line that dips twice as it goes toward the leading edge, forming a fat W. The Mottled Beauty was one of the few that visited our trap in the top garden, quite some distance from its cousin the Willow Beauty in the quarry trap. The former also flies earlier in the season (June-July). Despite their resemblance, the two actually belong to different genus: Alcis is the name of a daughter of Aegyptus, the Egyptian king who was born to the heifer maiden, lo, and the river-god Nilus; she had 50 brothers. Peribatodes is from ‘peri’ which means ‘round’ and ‘batōdēs’, overgrown with thorns, probably describing its habitat.

Green Arches (illustration)

Also new to me is the Green Arches (Anaplectoides prasina). As the name prasina (leek-green) suggests, its brilliant green color stands out against the clay ochre of the others. It was first recorded here in 2012 by Helen Levins and made another appearance last year around this time. I could have sworn I snapped an image of it for identification but later realized that that was done in my head, not on the camera…So, to make up for it, here (above) is an illustration of our moth under the name Polia herbida.


Post: Tung Chau (UPenn)