eng International Academy of Ecology and Environmental Sciences Arthropods 2224-4255 2017-6-1 6 2 36 46 1 article John A. Fornshell 1 2 Alessandra Tesei 1 2 Department of Invertebrate Zoology, United States National Museum of Natural History, Smithsonian Institution, Washington D.C., USA AGUAtech, Via delle Pianazze 74, 19136 La Spezia, Italy The Achelata, lobsters lacking claws and having a phyllosoma larva, are divided into two families, the Palinuridae or spiny lobsters and the Scyllaridae or slipper lobsters. Within the Palinuridae adults of two groups were identified by Parker (1884), the Stridentes that are capable of producing sounds, and the Silentes that are not known to produce sounds. The Stridentes employ a file-like structure on the dorsal surface of the cephalon and a plectrum consisting of a series of ridges on the proximal segment of the second antenna to produce their sounds. All species of Achelata hatch as an unpigmented thin phyllosoma larva. The phyllosoma larva of the Stridentes have a presumptive file-like structure on the dorsal cephalon. A similar file-like structure is found on the cephalon of one species of Silentes, Palinurellus wienckki, and some but not all of the phyllosoma larvae of the Scyllaridae. No presumptive plectrum is found on the second antenna of any of the phyllosoma larvae. Presence of a presumptive file-like structure on phyllosoma larvae of Silentes and Scyllaridae suggests that the ability to produce sounds may have been lost secondarily in the Silentes and Scyllaridae. http://www.iaees.org/publications/journals/arthropods/articles/2017-6(2)/sound-producing-organs-in-achelate-lobster-larvae.pdf Spiny lobster larva bio-acoustics slip-stick mechanism Phyllosoma