From zero to ossified: Larval skeletal ontogeny of the Neotropical Cichlid fish Cichlasoma dimerus

BERIOTTO, AGUSTINA C.; VISSIO, PAULA G.; GISBERT, ENRIC; FERNÁNDEZ, IGNACIO; ÁLVAREZ GONZÁLEZ, CARLOS A.; DI YORIO, MARÍA P.; SALLEMI, JULIETA E.; PÉREZ SIRKIN, DANIELA I.

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2023 vol. 284

0362-2525

The identification of skeletal elements, the analysis of their developmental sequence,and the time of their appearance during larval development are essential to broaden theknowledge of each fish species and to recognize skeletal abnormalities that may affectfurther fish performance. Therefore, this study aimed to provide a general description ofthe development of the entire skeleton highlighting its variability in Cichlasoma dimerus.Larvae of C. dimersus were stained with alcian blue and alizarin red from hatching to 25days posthatching. Skeletogenesis began with the endoskeletal disk and some cartilagestructures from the caudal fin and the splachnocranium, while the first bony structureobserved was the cleithrum. When larvae reached the free‐swimming and exogenousfeeding stage, mostly bones from the jaws, the branchial arches, and the opercle seriesevidenced some degree of ossification, suggesting that the ossification sequence of C.dimerus adjusts to physiological demands such as feeding and ventilation. The caudalregion was the most variable regarding meristic counts and evidenced higher incidenceof bone deformities. In conclusion, this work provides an overview of C. dimerusskeletogenesis and lays the groundwork for further studies on diverse topics, likedevelopmental plasticity, rearing conditions, or phylogenetic relationships.