Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Fīcē̆dŭlenses, ium, m. [ficedula], sellers of small birds, a comic name of a sort of soldiers, along with Placentini and Turdetani: opus est Ficedulensibus, Plaut. Capt. 1, 2, 60.