Hi I have been spotting a few of these mystery slugs in our garden recently. They are brown with darker brown markings like patches down their back. Could this mystery slug be a leopard slug? If it isn't could you tell me what species it is, as it is a bit unusual amongst my common garden slugs!
This individual was having it's breakfast on some spilled bird food...................Yum!!!
3.5-5(-6) cm*? Deroceras reticulatum. Some individuals are more spotted than others (and some are hardly spotted at all). (To be 100% certain it is not a D. agreste you sometimes have to dissect it, but when it is as flecked as this one: D. reticulatum). The commonest slug in NW Europe, BTW.