denticle

denticle, part of a conodont, a small toothlike fossil found in marine rocks representative of a long span of geologic time. Although they resemble cusps, denticles are generally smaller than distinct cusps and vary greatly in shape and structure. Denticles may be spaced closely to each other or separated by gaps of varying size; they may be distinctly formed or partially fused to each other. In shape, denticles may be needlelike, spiny, or saw-toothed. In...