[Crustacea] Last larval stage in development of Euphausiacea (including the cyrtopia stage), characterised by eyes no longer under the carapace, the progressive development of thoracic legs, pleopods, and photophores, and the progressive reduction in number of telson spines. The second antenna may change in form and function from a biramous natatory appendage to a sensory appendage with flattened scale and segmented flagellum. The pleopods are added progressively until the full complement of five setose pleopods is present. Pleopods appear first as non-setose rudiments, which become setose at the following moult. The furcilia phase concludes with the moult to a form with one terminal spine and two pairs of postero-lateral spines, the juvenile number. The number of stages is variable among species and within certain species.