it is a special "conical shape" inductor. that data sheet has a poor picture, so you can not see that the coils of the inductor have a varying diamteter. So while ONE loop of a coil might resonate at your specific frequency of interest, the coil before it is slightly smaller and does not resonate, and the coil after it is slightly bigger and does not resonate there.
These sort of "inductors" are used for biasing up broadband devices, like a laser diode working from DC to 40 GHz.