A B S T R A C TAs the demand for marine ornamental fish is ever increasing, the industry largely relies on collections from natural habitat due to insufficient breeding and seed production technologies. Fishes of the family Pomacentridae are popular in marine aquaria throughout the world. Among these, damsel fishes of the genus Dascyllus has high demand and are mostly collected from the wild. The present study forms the first-ever report on successful breeding and larval development of Cloudy Damsel (Dascyllus carneus Fischer, 1885). Though there are a few reports on breeding of other species of Dascyllus, there has been no report on the complete larval development of any of the species in this genus. This forms the first description of early larval development of a Dascyllus species. Using the copepod Parvocalanus crassirostris as first feed the larval rearing was done. Successful breeding and larval development were achieved from the wild-caught broodstock of D. carneus at Vizhinjam Research Centre of ICAR-CMFRI, India. Brood stock from the wild took 4 months to spawn, laid 6500-10,500 eggs per spawning and hatching rate ranged from 90.6 to 98.81%. Newly hatched larvae were the smallest among all the reported larvae of pomacentrid fishes and measured 1.95 ± 0.14 mm in total length. Yolk reserve was completely absorbed within 72 h of hatching. Preflexion stage is from 4 to 10 dph, flexion stage is from 11 to 12 dph and postflexion period is 13-15 dph. Larvae accepted only copepod naupliar stages as first feed and calanoid copepod P. crassirostris alone was fed until 25 dph. Larvae settled from planktonic stage in 22-23 days and all the larvae metamorphosed into juveniles by 50 dph. The egg development, larval development and larval pigmentation up to 50 dph has been described. The feeding protocols and feed size preference in relation to their age or mouth gape, the gut contents and mouth gape of the larvae caught from a feed trial with surplus copepods of all stages were analysed at regular intervals. Larvae preferred larger stages of copepods in later stages of their development. Finally larval feeding protocols were modified accordingly and better survival was observed. A final feeding regime has been developed and a strategy for the consistent hatchery production of this species was achieved. Different stages of copepod P. crassirostris were used till the settlement of planktonic stage of larvae and Artemia nauplii were used from 25 dph. The larvae were completely weaned to artificial diet from 50 dph.

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Cyclopoid copepod, Dioithona oculata, is a common free-living euryhaline species in tropical and temperate waters having potential as live feed in marine fish larval rearing. Here, the effect of salinity on adult and naupliar survival, total population, population composition, clutch production, clutch size, development rate and adult longevity was investigated. Adult copepods survived the abrupt changes in salinities from 15 to 50 ppt (parts per thousand). The highest naupliar survival was at 30 ppt (86.33 ± 2.84%) and the lowest at 15 ppt (12.6 ± 2.34%). The highest production was at 30 ppt (883.0 ± 5.5 individuals/L) and the lowest at 15 ppt (49.0 ± 6.56 individuals/L). The proportion of nauplii was higher at salinities from 20 to 40 ppt, whereas the total population of copepodites and adults was significantly less at 15 and 45 ppt. The highest clutch production was observed at 30 ppt (8.6 ± 0.54 clutches)and the lowest at 45 ppt (2.6 ± 0.54 clutches). Maximum clutch size of D. oculata was recorded at 30 ppt (19.2 ± 2.94 eggs/clutch) and minimum at 45 ppt (7 ± 1 eggs/clutch) respectively. Development time from nauplius to adult was significantly (p < 0.05) longer at 45 ppt (12.72 ± 0.03 days) and shorter at 20 ppt (9.06 ± 0.02). Adult longevity was significantly higher at 30 ppt (27 ± 1.0 days) and lower at 45 ppt (11.3 ± 1.15). Salinity changes significantly affected the production performance of D. oculata. The optimum salinity for mass culture of D. oculata was found to be 30 ppt.