Species of Acryptolaria Norman, 1875 (Cnidaria, Hydrozoa, Lafoeidae) collected in the Western Pacific by various French expeditions, with the description of nineteen new species

The species of Acryptolaria present in collections from several French expeditions in the western Pacific, mostly in the waters around New Caledonia and neighbouring areas, have been studied. The collection proved to be rich in biodiversity, since 29 species were found, of which 19 new to science, doubling the number of known species in this genus. All the species are described, including measurements, and figured. The unknown coppiniae of several previously described species have been found; these are also described and figured. The study confirmed the key role of the cnidome for species identification.