Arion fuscus · tamsusis smalžys

EN · dusky arion DE · Braune Wegschnecke LT · tamsusis smalžys, kislusis arionas LV · rūsas kailgliemezis

https://en.wikipedia.org/wiki/Arion_fuscus A 50–70 mm roundback slug. It is brown in colour, ranging from black-brown through olive-brown to orange and bright reddish-orange. Darker lateral bands are present. Dark pigment reaches under the pneumostome from back to front. The foot fringe is pale with thin lines. The sole is uniformly pale/translucent.The tentacles are pale or dark. It does not contract into a bell shape when stimulated. The Dusky Arion differs from other Arion species in its yellow-orange body mucus.