The identification of skeletal elements, the analysis of their developmental sequence, and the time of their appearance during larval development are essential to broaden the knowledge of each fish species and to recognize skeletal abnormalities that may affect further fish performance. Therefore, this study aimed to provide a general description of the 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 25 days posthatching. Skeletogenesis began with the endoskeletal disk and some cartilage structures from the caudal fin and the splachnocranium, while the first bony structure observed was the cleithrum. When larvae reached the free-swimming and exogenous feeding stage, mostly bones from the jaws, the branchial arches, and the opercle series evidenced some degree of ossification, suggesting that the ossification sequence of C. dimerus adjusts to physiological demands such as feeding and ventilation. The caudal region was the most variable regarding meristic counts and evidenced higher incidence of bone deformities. In conclusion, this work provides an overview of C. dimerus skeletogenesis and lays the groundwork for further studies on diverse topics, like developmental plasticity, rearing conditions, or phylogenetic relationships.

中文翻译：

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从零到僵化：新热带丽鱼科鱼 Cichlasoma dimerus 的幼虫骨骼个体发育

骨骼元素的鉴定、对其发育顺序的分析以及它们在幼体发育过程中出现的时间对于扩大每种鱼类的知识和识别可能影响进一步鱼类性能的骨骼异常至关重要。因此，本研究旨在提供整个骨骼发育的一般描述，突出其在Cichlasoma dimerus中的变异性。C. dimersus幼虫从孵化到孵化后 25 天用阿新蓝和茜素红染色。骨骼发生始于内骨骼盘以及尾鳍和颅骨的一些软骨结构，而观察到的第一个骨结构是锁骨。当幼虫达到自由游动和外源摄食阶段时，大部分颌骨、鳃弓和鳃盖系列的骨骼都出现了一定程度的骨化，这表明二聚梭鱼的骨化顺序适应了摄食和通气等生理需求。 。尾部区域的分节计数变化最大，并且骨畸形的发生率较高。总之，这项工作提供了C. dimerus骨骼发生的概述，并为进一步研究不同主题（如发育可塑性、饲养条件或系统发育关系）奠定了基础。