Early Ontogeny of Cichlids Using Selected Species as Examples

Area of Science:

• Ichthyology and Reproductive Biology
• Aquaculture and Conservation Science

Background:

• The genus Cichlasoma encompasses diverse fish species with varying reproductive strategies.
• Understanding embryogenesis and larval development is crucial for aquaculture and conservation.

Purpose of the Study:

• To comprehensively characterize the reproductive strategy, embryogenesis, and larval development in three Cichlasoma species: green terror (Andinoacara rivulatus), red discus (Symphysodon discus), and jaguar cichlid (Parachromis managuensis).
• To provide data that can inform reproductive biotechnology for these species.

Main Methods:

• Eggs were collected from five pairs of each species and incubated at 26°C.
• Embryonic development was monitored microscopically from fertilization to yolk-sac resorption.
• Key metrics recorded included egg number per female, egg size, embryogenesis duration, larval size at hatching, and yolk-sac resorption time.

Main Results:

• Jaguar cichlids produced the most eggs (average 2991), followed by green terror (922), and red discus (300).
• Egg sizes varied significantly, with green terror eggs being the largest (1.365 ± 0.16 mm³), and jaguar cichlid eggs the smallest (1.060 ± 0.05 mm³).
• Embryogenesis and yolk-sac resorption times differed among species, with red discus showing the shortest yolk-sac resorption (3 days) and jaguar cichlid the longest embryogenesis (2470 °H).

Conclusions:

• Significant variations exist in reproductive traits and developmental timelines among the studied Cichlasoma species.
• The data generated can support the development of reproductive technologies for aquaculture.
• Enhanced understanding of these reproductive characteristics can aid in the conservation of these fish in their natural habitats.