15 July 2015

15 July 2015 – The Waves

Single-dotted Wave (Ideae dimidiata)

Yesterday morning, while looking at the photographs from Thursday night’s trap, we came to the conclusion that a new species had arrived at Shandy Hall – the Single-dotted Wave (Idaea dimidiata). We had difficulty locating it in Humphreys & Westwood (their illustrated picture is included beneath) because its taxonomy has changed with the years – it is recorded as Ptychopoda lividata in their 1845 edition. The moth was not easy to identify; that can in part be attributed to its proclivity to show up in varying colors – from bleached cream to tawny brown; ours was of the former. At first we suspected it might be a pug (satyr or ochreous, even though the colorings did not match up), because of the precise resting position and shape of its wings – in our photograph it appears narrower than in the Field Guide. However, the discrepancies in colors and lack of exact pattern matchings made identification inconclusive; only after consulting with Dave Chesmore from the University of York were we able to label it a new species. The Single-spotted Wave is common throughout Britain, found mainly in damp locations. I have concluded that the easiest way to recognize it is through the matching large dark dots on the edges of its wings; and how its “lines” appear to be comprised of small, speckled dots, as opposed to clearly delineated colorings. 

Post by Ariel Smith

Single-dotted Wave (illustration)

Having completed our investigations it was then noticed that there was an image of the Single-dotted Wave as a miscellaneous moth on the sidebar of the blog – dated 2011.  It wasn’t a new species after all but had been captured and identified before the blog records were kept.

Riband Wave (Idaea aversata)

Trying to identify the pretty moth above, the colouring seemed to indicate that it must be a Smoky Wave – but it turns out to be a Riband Wave though greyer than usual.  Checking through old photographs of the Riband Wave posted on our blog, we found a second error in our archive – the moth beneath…

Small Blood-vein (Scopula imitaria)

…had been mistakenly identified as a Riband but should have qualified as a new species – the Small Blood-vein.  So the new total of 364 moth species is correct, but not as we thought.

The Small Blood-vein (Scopula imitaria) is not a common moth in North Yorkshire so we should have paid greater attention to its arrival in Coxwold.  The scientific name refers to a scopula (a small broom) and imitaria (to imitate or counterfeit). Your guess is as good as mine.

Small Blood-vein (illustration)