22 July 2016 - Bulrush Nibbler

Limnaecia phragmitella

‘It’s an upside-down Flame!’ was my first reaction to this moth, though in truth the two are nothing alike. Swayed by the four apple-seed-looking dots in a line and the pale tip with evenly spaced black streaks, I went straight to the Gelechiidae family, but realized that none of their dots had the right configuration. Knowing I was missing the obvious, I took a break and saved myself from what the Chinese call ‘drilling into a bull’s horn’, or persisting blindly, often to a dead end.

A casual leaf through Lewington's guide minutes later revealed its identity: Limnaecia phragmitella although it is represented in the book as having more of an ashy color and less conspicuous markings. Ours is a peacock compared to that one.

‘Limnē’, marshy lake; ‘oikeō’, to dwell. The generic name outlines its zones of activity in the fens and marshes. Phragmites australis, its designated foodplant, is responsible for the species name, though the real foodplant is bulrush.

Small Yellow Wave (Hydrelia flammeolaria)

I have saved this magnificent Small Yellow Wave (Hydrelia flammeolaria) for last because the grand, fire-and-water spectacle is a good relief for the eye after squinting at micros for too long. Not many moths have this lasagne of white and yellow. The Sandy Carpet (Perizoma flavofasciata) is one, but it lacks the black dots and is much bigger. This moth is about the size of a Small Fan-footed Wave and rests in a similar position, with both pairs of wings showing. My only reservation was about the shape of the abdomen, but it may have been just a difference between eggs and no eggs.

The juxtaposition in its name can be broken down into hudrēlos, meaning watery, and flammeolus, flame-colored. The dripping gold is more apparent on the wings of a freshly hatched moth, but you can catch a glimpse of it in ours at the base of the wing where it meets the thorax.

Post: Tung Chau (UPenn)