Monday, 18 August 2014

Cinnamon Sedge - Limnephilus lunatus.

The light trap came up with a number of new discoveries the other weekend. One of which stumped me for a while. I was convinced it was a micro moth, but the legs were very hairy and didn't quite fit. Neither did the wings. Well thanks to iSpot I was put straight. It's not a moth, but a Caddisfly. I'm not very good at this! But that said this chap, Limnephilus lunatus is quite attractive, also known as the Cinnamon Sedge. The 'lumatus' comes from the crescent shape on the edge of the wings. It is a well known species, especially among anglers. The larva doesn't use sand or other hard materials for building its case, it uses plant materials only. Most of the information I could find on L lunatus came from angling websites.

Caddis flies belong to the Trichoptera, and have been known to fishermen since the advent of fly-fishing and to the entomological for a longer time. Mouffet the author of the first English book on entomology (the 'Theatrum Insectorum') writes in 1658 of the great variety of 'cados worms' to be found in rivers and streams. The name possibly arises from the ancient name for a travelling cloth salesmen who pinned samples of their wares to their coat, they were known as 'cadice men' and it is possible the name 'Caddis fly' is a reference to the cases many Caddis-fly larvae build from bits of debris. The Latin name 'Trichoptera' comes from the Greek 'Trichos' = a hair and 'Pteron' = a wing, meaning hairy winged which is a good description of the adult or imago forms.  In fact Caddis flies are closely related to Lepidotera, and so I don't feel so bad at getting it so wrong.

There are about 7 000 named species world wide of which over 400 occur in Europe and about 190 in Britain. Fossil Caddis flies have been found as far back as the Cretaceous , and possibly from the Jurassic. 

Limnephilus lunatus is on of the few caddis flies which may be a pest. The numbers of larvae in Water Cress Beds may become enormous! That won't be a problem for the tiny pond we have in the garden, but water cress would be welcome. I wonder what's in the fridge?