Early development of the Neotropical fish known as long sardine Triportheus auritus (Valenciennes 1850) (Characiformes, Triportheidae)

• DOI: 10.1111/jai.14228
• Publication Date: 2021-06-05T10:46:59Z
• Authors: Ruineris Almada C...; Lucas Silva Oliveira; Fabíola Katrine S...; Diego Maia Zacardi
• Keywords: Snout; Characiformes; Fish fin; Barbel; Meristics; Dorsal fin; Teleostei

Larvae and juveniles of long sardine, Triportheus auritus, from the lower Amazon river was described, evaluating ontogenetic changes in their external mor­phology, pigmentation, fin development, morphometry, meristics. A total 93 individuals, 83 larvae 10 were analyzed, they captured monthly between 2014 2019 channel macrophytes aquatic stands alluvial plains located River. From each specimen, morphometric meristic data measured then growth pattern variables analyzed. The have an elongated body a fusiform shape, superior mouth, simple nostril, pigmented spherical eyes intestine, surpassing median region body. Initial pigmentation is scarce, but intensifies through development forming composed three longitudinal bands concentrated ventral, cephalo-dorsal lateral line regions. There are also pigments mandible, surrounding under swim bladder, intestine fins. sequence complete formation is: caudal, anal, dorsal, pectoral pelvic. number myomeres ranged 45 to 48 (25–29 preanal 17–22 postanal). Morphometric relationships indicated differential for measurable parameters, with abrupt snout length, head length height transition flexion postflexion stages. pre-dorsal distance showed decrease rate at threshold larval juvenile period. pre-pectoral pre-anal distances negative allometric growth. In conclusion, combination shape and, fins allow identification genus coupled myomeres, relationships, ray numbers anal ensure differentiation T. auritus other congeneric species. metamorphosis occurred mainly end period it related physiological ecomorphological characteristics