250 Francs CFA Titanoboa

Titanoboa cerrejonensis, the snake this coin commemorates, was excavated from the Cerrejón coal mine in Colombia beginning in 2009 — a fossil discovery that forced paleontologists to revise their models of post-extinction equatorial temperatures, since a cold-blooded animal of that bulk requires ambient heat well beyond previous estimates for the Paleocene. Senegal's involvement is purely jurisdictional; the BCEAO issues collector bullion under CFA franc denominations as a licensing arrangement, with no pretense of domestic relevance to the subject matter.