Actinic moth trap
No interactions present.
As RHoman says it is not possible to split these without looking at the genitalia. With a male (at least) the can be done on an anaesthetised moth without the need to dissect it - moderate pressure on the abdomen causes the relevant parts to be revealed.
Alternatively, you can look for the caterpillars instead - although the adult moths of these two species are very similar, the caterpillars are readily identified.
Entomologist and biological recorder
Lat/Lng: 51.5, -0.4
OS grid ref: TQ1689