Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This is the classic Spaghetti Western by Sergio Corbucci (the director of "Django") with the great whistling theme "L'arena" by Ennio Morricone that was used 36 years later in Kill Bill Vol. 2. But enough trivia. At the beginning of this film we see a bunch of peasant men working outdoors at a mine when they announce a lunch break and the men line up for the same single scoop of beans into a bowl that you see in every prison or work movie. One tells the guard there should be extra protein in the beans because it's Sunday. Another pulls a lizard out of his beans and the guard laughs and says that's your extra protein. The laborers (who are really revolutionaries) immediately pull guns and take over the mine. Their leader takes the lizard he found and forces the mine owner to eat it while all the revolutionaries laughs. The movie was made in Spain, so it's probably a real but dead Spanish lizard that resembles a small lacerta of one of the several species found in Spain. The lizard eaten appears to be fake, but tasty for sure.