Uncertain - an adjustment to records in the database

There has been a great deal of discussion, particularly on the Scottishmoths forum, concerning the separation of Uncertain from Rustic. This is an old problem; indeed the vernacular name “Uncertain” reflects the long-standing nature of the difficulty. It appears that of the two species in Scotland may be even more difficult. Furthermore, their separation by examination of their genitalia is unreliable because differences are so subtle
that they are subjective. The conclusion from the discussion appears to be that strong cross-lines are a good indicator for Uncertain but the most reliable feature for their separation is the colour of the hind wings. Uncertain has nearly uniform brown hind wings while those of Rustic are silvery with a greyish brown outer margin.

I have reviewed the seven records in my data-base (three for vc86, one for vc87 and three for vc99). I have decided that six of these, including two of my own, were not accompanied by photographs or specimens and cannot therefore be validated with sufficient rigour. I have therefore moved these six out of the vice county data-bases into a "to be confirmed" file. The photograph of the remaining record has been circulated and despite not showing the hind wing is considered by Jon Clifton and Roy Lewington to be typical of Uncertain. It is reproduced above.

All future claims for this species must be accompanied by specimens or by photographs that include pictures showing the hind wing.