Morfología externa del desarrollo larvario de Hemicaranx amblyrhynchus (Pisces: Carangidae) del sur del Golfo de México

Abstract

Se describe el desarrollo larvario de Hemicaranx amblyrhynchus con especímenes capturados en el sur del Golfo de México. Los ejemplares presentaron tallas desde 1.87 mm hasta 16.43 mm. Los ejemplares más pequeños presentan una cresta supraoccipital aserrada que se distingue todavía en el espécimen de 5.7 mm de LP y desaparece en los de talla superior. El cuerpo es moderadamente alto en la preflexión y aumenta ligeramente durante el desarrollo. Las aletas dorsal y anal son visibles a partir del espécimen de 2.65 mm de LN; el número de espinas y radios está casi completo alrededor de los 9.0 mm LP. Las larvas de H. amblyrhynchus pueden reconocerse por una mancha de pigmentos en la punta del hocico, que está conformada, entre otros, por melanóforos en el palatino.

Translated abstract

Larval development of Hemicaranx amblyrhynchus is described from wild specimens (standard length SL: 1.8-16.4 mm) caught in the southern Gulf of Mexico (N=25). A serrated occipital crest was present only in specimens smaller than 5.73 mm SL and a supraocular crest with a small spine in those between 4 and 5 mm. As in all larval carangids, the angle preopercle spine was conspicuous since the first stages. Supracleithral and posttemporal spines were present during flexion stage, and then disappeared in transformation stage. Body depth is moderate, increasing with development. The dorsal and anal fins start to be evident in the 2.65 mm NL specimen; total number of spines and soft rays are almost complete around 9.0 mm SL. The pelvic bud was observed in the 3.16 mm LP specimens. From the early stages, the larvae are very pigmented and could be recognized by a pigmentation blotch on the tip of nose, which is conformed by palatine melanophores among others. Larvae of H. amblyrhynchus occurred scarcely in the area; they were essentially recorded on the inner shelf, in surface waters, not deeper than 30 m. The present paper is the first larval record for the species in the southern Gulf of México.