EMBRYONIC AND LARVAL DEVELOPMENT OF THE FIREMOUTH CICHLID (Thorichthys meeki Brind, 1918)

Abstract

In this study, it was aimed to investigate the embryonic and larval development of firemouth cichlid (Thorichthys meeki Brind, 1918) fish in laboratory environment. The spawning and embryonic development of the eggs of the 5 pairs of broodstock fish used in the study took place at an average water temperature of 27±1°C. Spawning lasted about 60 minutes and the average number of eggs was 1159.40±91.92 pieces.  The long axis of the egg was measured as 1.47±0.01 mm on average, and the short axis as 1.14±0.01 mm on average. After fertilization, the first draft of the embryo was seen between 10.45-11.35 hours. Between 12.30-13.45, the first optical capsule is formed. In the embryo, the first somite was seen at 14.00-17.30, the first heartbeat at 18.00-23.30, the first blood circulation at 21.40-30.20 and the first movement at 22.00-31.00. Hatching took place between 38.20-51.55 hours. The average total length of the newly hatched larva was measured as 3.38±0.03 mm. Larva started to swim on the 5th day, consumed the yolk sac on the 8th day and started to take feed. The larva reached the appearance of an adult individual by the end of the 30th day, and on the 30th day the total length of the larva was measured as an average of 11.02±0.36 mm.