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The present study provides the complete report on the embryonic and larval development of pink ear emperor, Lethrinus lentjan (Lacepede, 1802). Eggs were obtained from captive-reared broodstock of pink ear emperors from 1-year of age maintained in a 10-tonne recirculating aquaculture system (RAS). The brood fishes spawned throughout the year without hormonal induction. Fertilized eggs (692.65 ± 6.67 μm) were pelagic, transparent, non-adhesive and with a single oil globule measuring 146.63 ± 3.51 μm. Description of the different phases of embryogenesis, namely the zygote, cleavage, blastula, gastrula, segmentation of the fish is provided. Additionally, the developments during larval development period after hatching, which extends till the completion of yolk-sac absorption (pre-larvae) and the end of metamorphosis (post-larval) are also included in the present study. The embryonic development was completed within 14 h 40 min after fertilization. The newly hatched larvae had an average body length of 1.39 ± 0.08 mm, with a yolk sac measuring 787.67 ± 42.65 μm. The mouth opening was observed at 2 days post-hatch (dph). The yolk sac was completely absorbed by 2 dph, and the preflexion stage began, and it continued till 14 dph. Notochord flexion began by 15 dph and extended to 20 dph. The appearance of the typical adult colouration and scale formation started by 22 dph and by 35 dph the larvae reached the juvenile stage. The data on the embryonic and larval development will help to standardize the larval rearing techniques for the species.

Pink ear emperor, Lethrinus lentjan (Lacepede, 1802), belonging to the family Lethrinidae (oder: Perciformes) is an important food fish in India, Arabian Gulf and other South East Asian countries. The present communication gives detailed information on its captive broodstock maturation in RAS, natural spawning, larval rearing and seed production for the first time. Fertilized eggs (714.21 ± 11.91 μ) were transparent, pelagic, non-adhesive with single oil globule (146.63 ± 3.51 μ). Green water system was used for larval rearing. Size of hatchling ranged from 1355.1 μ to 1534.6 μ and mouth (110–148.2 μ) opened on 2nd dph. Larvae were reared using copepods, rotifer, artemia and micro diet. Squamation and intense pigmentation on the body began by 22 dph and by 25–30 dph larvae started moving from pelagic to benthic realm. Larvae became juvenile (length – 19.2 mm; weight – 0.096 g) after 35 dph resembling the adult fish colourations and by 46 dph, they attained an average body length of 27.83 mm and average body weight of 0.276 g. Fishes spawned throughout the year in RAS without any hormonal manipulation. Average percentage survival at seed stage was 2.85 ± 1.41.

Steps taken for broodstock development of Neopomacentrus nemurus, Coral demoiselle (Bleeker, 1857) in a hatchery, its spawning and development of egg to the juvenile stage are described. Among the three treatments tried, only the trial using Parvocalanus crassirostris nauplii as the first diet helped in the development of larvae. Larval and post‐larval growth was studied for a period of 65 days post hatch. The larva measured 2–2.4 mm in total length at the time of hatching. The mouth size of larva at the time of hatching measured 237.92 μm. By the 5th day, the width of the larval body had significantly increased. All the fins were conjoined, except for the caudal fin which had begun its appearance on the 2nd day itself. The digestive system was functional by the 5th day and the copepod remains were seen in the digestive tract. The larva metamorphosed by the 15th day with fully developed fins and fin rays. On the 20th day, the larval body had begun to display signs of fin pigmentation. The larva assumed adult pigmentation by the 35th day. By the 65th day, the larva grew to a total length of about 27 mm and weighed about 0.56 g.

Marcia's anthias, Pseudanthias marcia Randall and Hoover, 1993, belonging to the subfamily Anthiinae (family: Serranidae) is a highly sought after marine ornamental fish mainly due to its vibrant pink shade. The present study reports the first successful captive brood stock development, spawning, and larval rearing of P. marcia. Brood stock was developed in a 5-ton recirculation aquaculture system (RAS) using 12 wild caught juveniles. After 6 months of rearing, the fish (8–9.5 cm size) started courtship behavior. Spawning occurred at 1900 to 2100 h. The eggs (mean size - 617.9 ± 14.9 μ) were transparent, pelagic, non-adhesive and with single oil globule. The eggs hatched out after an incubation period of about 14–16 h at a water temperature of 29 °C. Newly hatched larvae measured 1206.6 ± 100.02 μ in total average length and increased to 1852.9 ± 24.68 μ at 48 h post hatch (ph). Mouth opened at 48–50 h post hatch (ph) and measured 76 to 80 μ. Larval rearing trials were conducted using rotifer (L and S type), wild zooplankton, copepod nauplii, artemia nauplii and microparticulate diet. Primordial fin development started by the 10th day post-hatching (dph) (larval size ~2.9 mm) while the opercular and dorsal spines were fully formed by 15 dph (total length of the larva was 4.4 mm). Larvae metamorphosed to miniature adult shape by 32–34 dph and on 50 dph they reached the pink colored juvenile stage (42–43 mm) and at this stage, they were transferred to nursery rearing tank. Four treatments with different feed combination were tried and treatment III with wild copepod gave an average survival of 5.2 ± 1.07% and treatment IV with Parvocalanus crassirostris gave an average survival of 7.3 (±2.51) %.

Broodstock development, breeding, spawning, larval rearing and growth of black Amphiprion ocellaris in captivity are described in this study. The black ocellaris, a magnificent colour morph of A. ocellaris was bred in captivity at Vizhinjam Research Centre of ICAR-Central Marine Fisheries Research Institute (ICAR-CMFRI). Two adults, approximately 4-6 cm in total length (TL) were stocked in FRP tanks of 300 l capacity, under optimum water quality. The broodfishes were fed a combination of boiled mussel meat, boiled squid and semimoist feed (protein - 40 %, lipid - 9.5 %, fibre - 2% and moisture - 31%) twice daily at a rate of 3-5% of their body weight. After a period of 1.7 years, the fishes started showing courtship behaviour and initiated spawning. The oocytes were of 3-3.3 mm in length and 1.1-1.9 mm in width. Approximately 200-300 eggs spawned the first time and the number of eggs gradually increased in subsequent spawnings. Spawning was obtained at an interval of 12-14 days providing an average of two spawnings per month. The incubation period of the eggs were 7-8 days and the fertilised eggs hatched on the 8th day, soon after sunset, generally between 19.00 and 20.00 hrs. Different strains of cultured plankton like Isochrysis galbana, Nanochloropsis oculata, L-type rotifer Brachionus plicatilis, calanoid copepod Acartia southwelli and Artemia were used as feed for larvae. The newly hatched larvae with a total length of 5±0.16 mm metamorphosed to juveniles on the 40th day (18.87±0.07 mm). Black ocellaris is a highly priced clownfish and can be used to crossbreed with the normal orange coloured ocellaris clown fish to produce different colour variants. Keywords: Black Amphiprion ocellaris, Breeding, Broodstock development, Larval Rearing, Live feed, Variants

The morphological, anatomical and reproductive features of the little Indian squid, Loliolus (Loliolus) hardwickei (Gray, 1849) were studied based on samples collected from boat seine operated along the Vizhinjam Coast. The species was found to be a new entrant to the fishery along the Vizhinjam Coast. A total of 27 morphometric characters were measured and 13 indices were calculated and reported. Dorsal mantle length (DML) of the specimens ranged from 2.6 to 6.8 cm with a mean DML of 4.5±0.88 cm. The largest specimen observed was a male with DML 6.8 cm. Fully mature (Stage IV) specimens were found to have a higher gonadosomatic index (12.54±2.64 in females and 0.8±0.21 in males). Average length and width of spermatophores were 3.078±0.092 mm and 0.11±0.02 mm respectively. Samples with higher DML were in advanced maturity stages (Stage V). Size composition (DML) of samples revealed that 50% of squids were within the 4-5 cm size range.