The obverse of the coin features the Coat of Arms of the Republic of Lithuania, encircled with the inscriptions LIETUVA (Lithuania), 50 LITŲ (50 litas) and 2010.
Reverse:
The reverse of the coin bears the image of a fish, which is the Loach included in the Red Data Book of Lithuania. The fish is surrounded by the inscriptions VIJŪNAS and MISGURNUS FOSSILIS in the Lithuanian and Latin languages.