Arion franciscoloi Boato, Bodon & Giusti, 1983  

External: Slug grey, sometimes with yellowish or greenish hue, with a darker longitudinal colour band at each side, blurry at lower edge and with a white margin upside; skin with elongated tubercles surrounded by a fine reticulate pattern of dots; mantle 1/3 of body length, pneumostome in anterior half and with a pale border; head and tentacles bluish-grey; foot margin yellowish grey with small blackish spots; sole pale yellow; caudal mucus gland clearly evident; mucus colourless.

Resembles Arion hortensis with differences in anatomical characters, characteristic foot-fringe spotting, and position of genital aperture with respect to the respiratory orifice (located between right upper tentacle and slit of repiratory orifice).