Type specimens of flashing fireflies (Coleoptera, Lampyridae, Luciolinae) in the Naturalis Biodiversity Center, Leiden (RMNH) collection were documented. Specimens explicitly marked or indicated as types belonging to the lucioline fireflies were investigated with each specimen and its accompanying labels photographed, and its morphological characters analysed and compared with the original species description. The genitalia dissections of selected types enabled redescription and clarification of the taxonomic status of seven name-bearing type specimens. This study provides the first redescriptions of holotypes, designation of lectotypes for five species, and confirmation that two of these belong in the genus Luciola s. str. A lectotype and paralectotype were designated for two specimens of Luciola cerea Gorham, 1882 which is confirmed to belong to the genus Curtos Motschulsky, 1845. Atyphella testaceolineata Pic, 1939 was redescribed and figured based on the holotype (an incomplete specimen). We assigned Luciola laticollis Gorham, 1883 and Luciola nicollieri Bugnion, 1922 to Luciola sensu stricto and Luciola picea Gorham, 1882 to species inquirenda. The identity of Pteroptyx decolor Olivier, 1911 is finally confirmed as a close Indonesian relative of Pteroptyx valida Olivier,1909 and a lectotype is designated. In addition, we take the first opportunity to present pictures of the original holotype of Pygoluciola stylifer Wittmer, 1939. We also discuss the challenges taxonomists face in identifying specimens and how detailed dissections allow us to present descriptions of certain male features not previously addressed.
