Allotrichia pallicornis (Eaton, 1873)

Allotrichia pallicornis is one of 28 members of the Family Hydroptilidae found in Ireland, and the only member of its genus. It is a species whose larvae can be found in streams and moderate to fast-flowing rivers. Its substratum preference ranges from sand and fine gravel to cobble. Allotrichia pallicornis has a case made of algal filaments held together by silk and is strongly laterally flattened. In terms of feeding, this species is entirely a grazer/scraper.

Allotrichia pallicornis is separated from other members of the family by the lack of dorsal and ventral ovoid processes, a laterally compressed case incorporating algal filaments (loosely attached), 2nd & 3rd legs no more than 1.5 times as long as the 1st leg, anal proleg without a gill filament and the lack of dark markings on the mesonotum and metanotum.

Adults of Allotrichia pallicornis can be found on the wing from May to August.

For details of published records of Allotrichia pallicornis, visit the National Biodiversity Data Centre page here.

Allotrichia pallicornis


Barnard, P. and Ross, E. (2012) The Adult Trichoptera (Caddisflies) of Britain and Ireland. RES Handbook Volume 1, Part 17.

Graf, W., Murphy, J., Dahl, J., Zamora-Muñoz, C. and López-Rodríguez, M.J. (2008) Distribution and Ecological Preferences of European Freshwater Species. Volume 1: Trichoptera. Astrid Schmidt-Kloiber & Daniel Hering (eds). Pensoft, Sofia-Moscow.

O’Connor, J.P. (2015) A Catalogue and Atlas of the Caddisflies (Trichoptera) of Ireland. Occasional Publication of the Irish Biogeographical Society, No. 11.

Wallace, I.D., Wallace, B. and Philipson, G.N. (2003) Keys to the Case-bearing Caddis Larvae of Britain and Ireland. Scientific Publication of the Freshwater Biological Association No. 61.

Last updated: 01/11/2019