• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.447-456
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• 1987

The osteological development of the larvae and juveniles of Prognichthys agoo was examined on the laboratory-roared materials of 5.06-20.01 mm in mean total length(MTL). Cranium, vertebrae, caudal skeleton, siloulder girdle bone, pelvic girdle bone, pterygiophore and jaw bones were descriued in detail to examine the sequences of ossification. Ossification of the cranium took place at ca. 5.06 mm of MTL in exoccipital, basioccipital, parasphenoid. Ossification of the visceral skeleton occurred in areas where active movements of bones were required, notably in the parts for feeding and respiration. Vertebrae began to develop from the anterior end and to ossify posteriorly. Neural and haemal spines of vertebrae ossified always prior to the corresponding centra. Urostyle bone developed as an elongated bone from the early larvae and ossified prior to the centra caudal part. In jaw bones, maxillary and a part of dentary appeared first at 5.06 mm of MTL and attained a fundamental structure at 9.30 mm of MTL. Ossification of all bones was nearly completed at ca. 20.01 mm of MTL.

• Korean Journal of Ichthyology
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• v.12 no.4
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• pp.230-235
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• 2000

The purpose of the present study was to describe the morphological and skeletal development of the larvae and juvenile of Ilisha elongata(Bennett). The larvae(mean 5.02 mm in total length, TL) opened the mouth and anus with 36~38+15~16=51~54 myotomes, and anus located about 73.0% of TL. The clavicle of shoulder girdle was ossified. The larvae(mean 7.82 mm in TL) have all fin-fold differentiated and its caudal notochord began to flex. Parasphenoid of cranium and dentary of the lower jaw were ossified. The caudal notochord of the larva(mean 9.84 mm) was flexed $45^{\circ}$, and anus located about 67.0% of TL. The body height of the larvae(mean 23.32 mm in TL) were 18.0~20.0% of TL, and the aggregate numbers of all fin rays were completed. Ossification was completed in the larva of mean 26.52 mm in TL.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.30-39
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• 2024

This study examines the osteological development of the Bartail Flathead Platycephalus indicus in the cranial, vertebral, caudal bones and pelvic, sholder grilde bones for the purpose of taxonomic studies. Adult P. indicus were collected from the Yeosu coast and artificially fertilized. Juveniles were reared at 18.5~21.8℃ (average 20.0℃±0.5℃). At 3 days after hatching (total length (TL) 3.49±0.32 mm), the parasphenoid and clavicle began to ossify. At 14 days after hatching (6.34±0.24 mm), the parietal and exoccipital bones of the cranium, the six branchiostegal rays of the hyoid, the urostyle of the caudal bones and the actinost of the shoulder girdle had ossified. At 39 days after hatching (11.39±0.86 mm), the preorbital and suborbital bones of the cranium were ossified, ossification of the pelvis girdle had begun, and the sholuder girdle was fully ossified. The number of vertebral columns were 26. At 45 days after hatching (12.63±0.62 mm), the nasal and supraorbital bones were ossified and the entire skeleton of the juvenile was completely ossified.