Plectranthias pelicieri is described as a new species of anthiine fish from six specimens collected in 50-70 m at Mauritius. It is distinct in having dorsal rays X, 16 or 17; branched caudal rays 15; pectoral rays 13, none branched; lateral-line complete with 29 pored scales; 4.5 rows of scales on cheek; scales dorsally on head not reaching a vertical at rear edge of orbit; 3 ventrally-directed to antrorse spines on ventral margin of preopercle; third dorsal spine longest; a slender membranous flap from tip of larger spines of dorsal fin; an emarginate caudal fin; and a distinctive red and yellow color pattern with pale blue to white vertical lines on body.
A Seychelles specimen of P. gardineri (Regan) is illustrated for the first time in color.

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To examine a role of calcium excretion into gallbladder bile in calcium homeostasis, a single administration of Stannius corpuscle extracts from rainbow trout or 17β-estradiol was given the rainbow trout, Oncorhynchus mykiss, and serum and bile calcium concentrations were analysed by flame photometry. Calcium concentrations were approximately 3.7 times higher in bile than serum in the control fish. Calcium-roaded fish showed marked increases in serum and bile calcium conentrations. The simultaneous administration of the extracts effectively reduced the hypercalcemia after 3h. However, the extracts did not have any effects on bile calcium concentrations at any examination times. 17β-estradiol induced marked hypercalcemia with a peak 10 days after administration. In contrast, bile calcium concentrations decreased to a minimum level on the day showing a mirror profile to changes in serum calcium concentrations (r=-0.95). These results inidcate that gallbladder bile calcium is not involved in the hypocalcemic regulation by Stannius corpuscle extracts, but decreases in concentration as a result of vitellogenin synthesis in hepatocytes.

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The distribution and life history of the catadromous cottid fish, Trachidermus fasciatus were studied in rivers discharging into Ariake and Yatsushiro Sounds, west Kyushu, Japan. The fish were found to inhabit rivers located between the Yabe River of Fukuoka Prefecture and the Honmyo River of Nagasaki Prefecture. Juveniles were found in May pointing upstream just below dams which were located at the lowest point in the rivers. Until their first autumn, the fish remained in small areas below the dams. Most of the dams were located at the upper end of the tidal reaches of the rivers. We did not find T. fasciatus inhabiting areas above the lowest dam. Their present distribution, which is restricted down-stream and confined to unnaturally small areas, is thought to be caused by the construction of the dams. The fish do not appear to migrate as far upstream as previously reported. The fish mature and migrate downstream in their first autumn or winter, when they are about 150 mm in total length. No age 2 fish were found in the rivers surveyed. Juveniles smaller than 19mm in total length mainly fed on copepods, and their main food changed from aquatic insects to fish after their upstream migration.

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The osteological development of the neurocranium of Micropogonias furnieri (Perciformes, Sciaenidae) is described with special attention to the substitution of cartilage by bone. Preflexion, flexion, postflexion larvae and juveniles from 3.8mm NL to 48.3mm NL and adult of 380 mm SL were cleared and stained. The preflexion larvae, 3.8mm NL to 4.2mm NL, present a completely chondrified neurocranium. In the flexion larvae from 5.8mm NL to 7.8mm NL the frontal and supraoccipital are present as a transparent lamina and the ethmoidal and otic regions are chondrified. In the postflexion larvae around 8.0mm SL to 14.0mm SL, a number of ossification areas are observed such as the supraorbital ridge of the frontal, the supraoccipital and supraoccipital crest, the parietal, the parasphenoid, part of the exoccipitals and the wall of the trigeminofacialis chamber. In the juveniles of approximately 14.0mm SL to 48.3mm SL major ossification is at the ethmoid, orbital and otic regions, the ethmoid being the most ossified region. The vomer and the prefrontal are less ossified; the frontal is partially ossified but with incomplete or absent ridges. The parietal, the occipital and supraoccipital ridge ossify rapidly. The otic capsule ossifies more slowly, presenting a large cartilaginous area at 48.3mm SL. The parasphenoid and basioccipital have got a large ossified extension since 14.0mm SL. In the adult of 380mm SL all the regions are completly ossified. The supratemporal suture with the pterotic is not distinguished; these structures fuse very early in the development process.

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Using the ichthyoplankton samples collected in the southeastern Brazil Bight (from 23°S to 29°S), morphological development of four species of Symphurus larvae and pre-settlement juveniles are described. Larvae of four species are identified based on distribution pattern of pigment on the dorsal and ventral margins of trunk and the length of first five dorsal fin rays. All four species have a crest consisting of elongated dorsal rays. Symphurus ginsburgi larvae have one short first dorsal finray followed by four long rays and a pair of melanophores are visible on the dorsal and ventral margins of the trunk at about one-third of body length from preflexion stage. Only S. ginsburgi of the four species reported has a conical appendix attached to the trailing gut coil. Symphurus kyaropterygium also has one short dorsal finray followed by four long rays, but can be distinguished from the former species by pigment pattern, i.e. there are four groups of melanophores along the dorsal margin of the trunk. Symphurus tessellatus has one short finray followed by two long rays and seven groups of melanophores on the dorsal margin of the trunk. Symphurus trewavasae has four long dorsal finrays and six groups of melanophores along the dorsal margin of the trunk.

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Repomucenus richardsonii and R. valenciennei eggs were obtained from captive spawners, and the larvae were raised to the juvenile stage. Total lengths (TL) of newly-hatched prolarvae were 1.17±0.04mm and 1.11±0.03mm, respectively. Each species had 8-9+11-12 myomeres and a large oval yolk sac. Developmental changes in the two species were similar: absorption of the yolk was completed at 5-6 days after hatching at ca. 2.2mm TL, all fin rays were fully developed at ca. 5.5mm TL, and the transition to a demersal life style was completed at ca. 10-11mm TL. The postlarval stage of the two species can be distinguished by the melanophores on the ventral edge of the notochord, on the branchiostegal membrane, and on the ventral finfold. The juvenile stages can be distinguished by the melanophores on the branchiostegal membrane, on the pelvic fins, and just above the lateral line and the infraorbital canal pattern.

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Sexual pattern, group structure and inter-group movement of the anemonefish, Amphiprion clarkii, were investigated on a coral reef at Sesoko Island, Okinawa, where host sea anemones were sparsely distributed. An adult group usually consisted of an adult pair, and a varying number of subadults and juveniles. Adults rarely moved between groups because they already occupied large host sea anemones, which were requisite to reproduction. If a female disappeared from a group, the male usually changed sex and a subadult became male. Subadults often moved between groups if it resulted in higher size order. There existed subadult groups, each of which consisted of one or two subadults and a varying number of juveniles. The largest and the second largest subadults in a group became female and male respectively if they occupied large hosts without adults. Subadults never became adults in the presence of adult pairs. It was concluded that labile sexuality of subadult A. clarkii is maintained as a mate acquisition tactic irrespective of host density even under the conditions where the habitat is saturated with breeders.

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The morphology of the throat barbels of Cirrhoscyllium japonicum is described in detail. Each barbel is supported by a basal cartilage and a cartilaginous core, and innervated by ramus mandibularis externus from truncus hyomandibularis VII. Neither muscles nor taste buds or other sensory receptors are associated with the barbels, which are thought to function as sensory organs, responding to physical or mechanical stimulation. Comparison of the throat barbels with head appendages found in related shark groups suggests that the former are not homologous with any of the latter, but are better interpreted as an autapomorphic character of the genus Cirrhoscyllium.

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A new platycephalid, Grammoplites knappi, is described from specimens from the South China Sea (off Sarawak, Borneo Island, the Gulf of Thailand and Hainan Island, China). The species is distinguished from other species of Grammoplites by the following combination of characters: 5 or fewer gill rakers on the lower arch, narrow interorbit, large eye diameter, short uppermost preopercular spine, no papillae on lips, small body scales and pored lateral line scales with posteriorly-positioned ctenii and a single exterior opening on the posterior margin. A key to the five species of Grammoplites is presented.

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Spawning behavior of Chaetodontoplus duboulayi was recorded for the first time in an aquarium. Dimorphic characters associated with sex were recognized in color pattern and caudal fin shape. From 14 March to 27 April 1992, a pair spawned almost daily. Spawning took place between about 50 min before and 70 min after the mercury lamps went out in the evening (18: 40-20: 40). A second spawning was observed on three evenings. The number of eggs per spawning ranged between 5, 000 and 33, 000. Compared with the courtship of other pomacanthid species, the male's rapid swimming, which was its only courtship display, and the female's active display, including soaring and rapid swimming, were unique to C. duboulayi. Eggs were pelagic and spherical, 0.92-0.97mm in diameter, and had a colorless transparent chorion and a yellowish transparent oil globule of 0.22-0.24mm in diameter. Hatching occurred 24-25hrs after spawning at 25.0-25.4°C. The newly-hatched larvae, 2.40-2.63mm in total length (TL) with 12+16=28 myomeres, had an elliptic yolk sac, which extended beyond the snout. The yolk was segmented. The oil globule was located at the rear end of the yolk sac. The larvae of C. duboulayi up to 48hrs after hatching were generally similar to those of other pomacanthid species, but distinguishable by the pigmentation patterns.

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A new gobiid fish, Stonogobiops pentafasciata, is described on the basis of four specimens from Kashiwajima Island, Kochi Prefecture, Japan. It differs from other species of the genus in having a diagonal black band from chin, through eye, to occiput; first dorsal fin rounded and clear; posterior part of pelvic fin jet black; scales on anterior part of body embedded.

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We surveyed fish fauna at 3 boulder sites in Uchiumi Bay, Shikoku Island, Japan. Numbers of fish species and individuals of each species were recorded along 2 lines (50 and 100m) at each site, using SCUBA in September 1992. A total of 126 species were recorded; about 66% of them were tropical or subtropical fishes. Number of temperate species was similar among the 3 sites (26-28 spp.). Numbers of tropical or subtropical species (30-60 spp.) was greater at the sites where the coral coverage was higher (4-37%). The location in the bay and the strength of water current in each site are also suggested to affect recruitment and density of tropical fishes transported by the Kuroshio Current. The fish fauna of Uchiumi Bay was compared with those of 16 localities of southern Japan. The number of species common to Uchiumi Bay was relatively high in Kushimoto, Kagoshima Bay and Shirahama; all the 4 localities are situated near the border between the warm temperate region and the subtropical region.

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Oxygen consumption rates of larval Japanese whiting, Sillago japonica, were examined at various developmental stages from hatching (Day 0) to just before the juvenile stage (Day 28). The oxygen consumption rate per larva increased exponentially with larval age throughout development. The weight-specific oxygen consumption rate increased with age from hatching to Day 13, subsequently decreasing to Day 28, being subject to diurnal variation throughout, with higher rates during daytime. The latter were more variable than nighttime rates, which were almost equal to the values observed at hatching.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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