Abstract

A single lanternfish juvenile (7.56 mm in standard length) was collected from the eastern sea of Jeju-do Island in May 2024 using Bongo net, and then identified Lampanyctus alatus based on mitochondrial DNA cytochrome c oxidase subunit I sequences. We provide a detailed morphological description of Lampanyctus alatus juvenile and propose a new Korean name, as this species has not previously been recorded in Korea. L. alatus has several distinctive morphological traits as follows: rounded eyes, a relatively large head, the presence of second branchiostegal (Br₂) and fifth pectoral organs (PO₅) photophores, and presence of melanophores on the parietal, nape, and base of the pectoral fin. When compared our L. alatus juvenile with the congeneric species L. fernae, they are distinguishable in the number of fin-rays, melanophore distribution, and the presence of the PO₅ photophore. We propose ‘Nal-gae-saet-bi-neul-chi’ as the new Korean name for this species.