Morphological and osteological development of larval Prolatilus jugularis from Bahia Independencia, Pisco, Peru is described. 232 specimens were collected with plankton nets in 2000; 40 individuals (2.5-25.9 mm) from new hatched larvae through transformation were assembled using general morphological features and pigmentation patterns. P. jugularis larva hatches at approximately 2.5 mm. Notochord flexion begins at ca. 5.7mm and ends at ca. 10.6 mm, and transformation occurs at ca. >10.6 mm BL. The most important diagnostic features of the larvae include a pigmented robust body shape, larval P. jugularis are moderately deep-bodied and compressed, the head is large and broad. The small larvae are well developed, the mouth is functional, spines forming at the head, the gut is tubular and folded into a broad "S" shape, and the preanal length is more than half of the body length. Pelvic fins below or slightly in front of pectorals, mouth protractile and terminal, caudal fin truncate to deeply crescentic, dorsal fin continuous, which extends over the length of the dorsal part of the body, with III-IV short spines and 21-23 soft rays, anal fin with 21-23 rays, first one or two may be spinelike, lateral line continuous. It has I,5 Pelvic fin rays, 9+8 principal caudal rays and 36-37 myomeres.