The smallest moth with the biggest name!

Eilish Rothney,  Trinity Broads Warden


The lovely little moth I have in mind is Colephora hydrolapathella – a bit of a mouthful, it does have an English name: “The Water Dock Case-bearer” not much shorter! 

With a wingspan of only 13-14mm this tiny moth is classed as a “micro-moth” and there are more than 1,400 species of these in the UK. What is so special about this one I hear you asking? Well it is one of the rare micro-moths, designated a UK Biodiversity Action Plan species and difficult to identify in the adult form. The only guaranteed way to identify it correctly is to dissect the poor little blighter. But the good news is – the larval form over-winters in a small case, only found on Water Dock (hence the name, I always like it when it does what it says on the tin!).



So first we need to know where the water dock grows and this is often in very wet inaccessible areas so the species is probably under-recorded. But if you like having a damp walk in the fresh winter air -look out on dyke edges for the brown winter leaves and tall stems of this dock. Check these tall stems all along their length and spot the 10mm long cases. If you are lucky enough to spot one please place the stem back where you found it and send us in your records! If you are not on a NWT reserve then please send you records to:  tdavis@butterfly-conservation.org 

Another reason this little moth is special is, it is what we call an indicator; it tells us by its presence, or absence, how healthy and how diverse the habitat is. This in turn tells us whether we are managing the habitat correctly. Farmers – if you find this on your land it will also inform the agri-environment scheme that you have good wetland habitat and dykes. Although not rare, the Water Dock itself is mainly found in central and south east England, sometimes called “Greater Water Dock” with flower stems up to 2m tall and large leaves.

I remember from my childhood the phrase “look after the pennies and the pounds look after themselves!” Well I think it can be true in nature, if we look after the little vulnerable things then the bigger things will benefit as well and we will have a rich and diverse habitat.