Caddisflies or Trichoptera, (meaning, from the Greek trichos a hair and pteron a wing; hairy-wings)

This is one of the few insect groups where, at least in so far as the British fauna is concerned, the majority of the larvae are known and both adults and larvae can be identified to species. Careful manipulation of both larval and adult specimens, under the microscope, is required in order to see characters clearly. In the larvae, some important characters are the form and position of gills, hairs on various parts of the body and legs and the shape, position and colour of sclerotized plates on body segments, along with head patterns. In the adults, examination of the wing venation (front and hind wings) and genitalia, as well as spur formula are among the characters used to determine a species identification. Though some characters can be difficult to assess, the identification of the order, in both its life stages is relatively straight forward, using the excellent keys (listed below). These volumes also provide much interesting information on their ecology as well as instructions on collection and preservation. The majority of the larvae make, and live in, portable cases, but a considerable number of them do not. All the species in any particular family are either case bearing or caseless. This is not; however; as straight forward a division as it might seem, as some case-bearing larvae wait until their final instar before constructing a case and some flowing water species are known to abandon their cases from time to time to drift with the current. Caseless larvae construct a fixed shelter when they are ready to pupate.

Limnephilus politus in its amazing case. (Photo Credit Sharon Flint)

Keys to adults:-

Macan T.T.(1973.) A Key to the Adults of the British Trichoptera. Scientific publications of the Freshwater Biological Association, No.28.

Barnard and Ross (2012). The Adult Trichoptera (caddisflies) of Britain and Ireland. Handbooks for the identification of British Insects. Vol.1 Part 17.

Keys to the larvae:-

Edington, J.M. and Hildrew, A.G.(1995). A revised key to the caseless caddis larvae of the British Isles with notes on their ecology. Scientific publications of the Freshwater Biological Association, No. 53.

Wallace, I.D., Wallace, B. and Philipson, G.N. (2003) Keys to the case-bearing Caddis larvae of Britain and Ireland. Scienfitic Publications of the Freshwater Biological Association, No.61.

You can send records to the Trichoptera Recording Scheme here.

Adult Caddisflies can be humanely euthanised by putting them into a domestic freezer for a few hours. Each sample can then be preserved in 70% alcohol in a specimen jar for later identification or, if assistance with identification is immediately available, put into an envelope and posted, if necessary. Some Caddisflies can be identified reliably from good quality photographs, but most are difficult to reliably identify this way unless a high quality image of the genilalia and wing venation is provided. Please make sure the following data are recorded with any specimens: date of capture, six figure grid reference, catch method, habitat, name of collector. Please write this in pencil on a piece of paper; this is especially important if you are putting the label into a specimen jar containing alcohol. Records can also be put into https://www.brc.ac.uk/irecord/

Thankyou

The Review of the Status of British Caddisflies Report can be down loaded from this link:

Stoneflies, belonging to the Insect order Plecoptera, are so called because the adults of the larger species may often be encountered walking, and hiding, amongst the rocks on the shore after emerging from rivers and streams.   Many of the smaller species are active flyers and may also be found on tree trunks and amongst bankside vegetation.   The scientific name refers to the complex pattern of venation in the wings which, in some species, resembles braiding when the wings are folded along the back when at rest.   Adults may be fairly short lived as many of them are not known to feed; although they do drink; but there is evidence (shown by gut content analysis) that some species do feed on lichens and pollen.  The juvenile stages, at least of the larger species, may take up to three years to grow to maturity.   Both adults and mature juveniles can be identified to species using the keys in Hynes (1993).

Hynes, H.B.N. (1993). A key to the adults and nymphs of the British Stoneflies (Plecoptera) with notes on their Ecology and Distribution. Scientific Publications of the Freshwater Biological Association No. 17.

The Plecoptera Recording Scheme can be viewed here at the Riverfly Partnership's website.

Stoneflies are occassionally found in light trap by-catches. Some can be identified from qood quality photographs, but, most require more detailed examination, usually on deceased specimens, in order to identify them reliably to species. Photographs of the relevent characters will be necessary if records are to be veritied on iRecord. You can upload Stonefly records into: https://www.brc.ac.uk/irecord/

In Britain the white-clawed crayfish is our only native crayfish and is our largest freshwater invertebrate. It lives in clean, relatively hard, mineral-rich waters with a pH of between 7 and 9 and calcium concentrations above 5mgL -1. It is widespread in clean, calcareous streams, rivers and lakes in England but many populations have been lost since the 1970s.

Within the last decade the White-clawed Crayfish has been the subject of numerous site and river catchment surveys within the Yorkshire region, the results of which are being collated by the Environment Agency and resulted in the foundation of the North Yorkshire Crayfish Forum in 2019, which expanded to Yorkshire-wide in 2024.

Research paper: Gazetteer of White-clawed Crayfish in Yorkshire, by Colin Howes

Links and Downloads

Checklist of flatworms

Checklist of leeches

Status of British Caddisflies report can be downloaded from this link: http://publications.naturalengland.org.uk/publication/5436150266200064

Check out the Riverfly Partnership.