I've seen a few larger folk art pull toys (primarily dogs) made in this articulated manner, allowing the body to curve and snake, but I've never seen a crocodile, or one of this smaller (perfect!) scale. With a bit of a similar feel to those old Pennsylvania folk art turtle step stools I really love, and with a most excellent and perfectly aged paint job: sponged black paint animating the dark green, and yellow spots on top of that, plus eyes that remind me of fried eggs! Earlyish 20th century I believe, on antique tin wheels that roll along. 

12" l x 1" across at wheels x 2 1/8" t. Excellent condition, and just excellent!