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Volume 30, Issue 4
Displaying 1-15 of 15 articles from this issue
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Kenji Mochizuki, Mitsuhiko Sano1984 Volume 30 Issue 4 Pages 335-340
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA new percichthyid fish, Neoscombrops calauticus, is described on the basis of 15 specimens from the Caribbean Sea.It is distinguished from congeners by the combination of the following characters: pored scales on lateral line 44-48 (mean 46) to hypural end;gill rakers on lower part of first arch 14-18 (mean 17);teeth on lateral side of lower jaw greatly reduced in size;some scales on body ctenoid.All specimens of the species were captured at the depths between 180 and 650m mainly by shrimp trawls.View full abstractDownload PDF (3127K) -
Kazunari Yano, Sho Tanaka1984 Volume 30 Issue 4 Pages 341-360
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSScymnodon in Japan is represented by two species, S. squamulosus and S. ichiharai sp.nov. The new species differs from other species of the genus by the shape of 1st dorsal fin, dermal denticles and lower teeth, the head length, and the interspace between the pelvic and caudal fins. S. squamulosus is redescribed from 12 specimens. S. obscurus is regarded as a junior synonym of S. squamulosus. A key to the species of Scymnodon is given. Scymnodon is closely related to Centroscymnus.View full abstractDownload PDF (18383K) -
Masao Katayama, Yasuhiko Taki1984 Volume 30 Issue 4 Pages 361-367
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSSpecimens of the centropomid genus Lates occurring in Japanese waters are compared with those from the Philippines, Thailand and Australia.Specimens from localities other than Japan are morphologically identical, and referrable to L.calcarifer (Bloch).Whereas, the Japanese specimens are found to represent a distinct, undescribed species, with clear morphological differences from L.calcarifer, although L.calcarifer was originally described by Bloch on the basis of a material allegedly from Japan.The Japanese form of Lates is described here as L.japonicus sp.nov.This new species differs from L.calcarifer in the relative depth of the body, relative length of the third dorsal and second anal spines, pectoral fin ray count, squamation, and gill raker count.View full abstractDownload PDF (1190K) -
Ronald Fricke, Ulrike Heckele1984 Volume 30 Issue 4 Pages 368-370
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSAbstract A new callionymid fish, Callionymus sphinx, is described on the basis of one male specimen from Shoal Bay, Northern Territories, Australia.It differs from the nearest allied species, Callionymus erythraeus Ninni, 1934, by the different shape of the first dorsal fin (4th spine short, not filamentous), the more elongate last ray of the second dorsal fin, the preopercular spine shape, the pectoral fin length, and the color pattern of the first and second dorsal fins, anal fin, head, and body (no saddle-like blotches).View full abstractDownload PDF (520K) -
C.E. Dawson1984 Volume 30 Issue 4 Pages 371-373
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDiffering from other known pipefishes with caudal fin and continuous superior and inferior body ridges by the combination of 19-20 trunk rings and lateral trunk ridge ending on the 10th-13th tail ring, this new species is provisionally referred to the genus Festucalex Whitley 1931, pending collection of adults.The planktonic type material was taken in the upper 0-167 m over depths of 1, 280-4, 825 m in the Sulu and Celebes seas and off northwestern Irian Jaya.Subadults-adults are expected to occur in depths>40m.View full abstractDownload PDF (2300K) -
Keiichiro Mori1984 Volume 30 Issue 4 Pages 374-392
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThe morphology and ecology of Lutjanus vitta in early developmental stages were studied.Materials were collected with plankton nets, seines and trawls from 1975 through 1977 in Yuya Bay located in the southwestern part of the Sea of Japan.Larvae and early juveniles of the fish are outstanding in having an elongate second dorsal spine, pelvic spines, and pelvic rays.The body is compressed, and the head is armoured with spines and bony projections on the maxillary, posttemporal, supracleithrum, postcleithrum and four opercular bones.The fish attain full fin ray counts at about 10mm SL (= standard length) and specific coloration around 24mm SL.Relative growth of the elongate fin elements consists of four stanzas delimited by three growth inflexions which occur at about 7, 16 and 32mm SL.Close correlations between morphological and ecological changes were observed.Larvae less than 7mm SL spend planktonic life in the open sea, showing rapid growth in fin elements, adapting to the life mode.At about 7mm SL, a sharp downward inflexion occurs simultaneously in these fin elements, and the negative growth rate is maintainted until the fish measure about 16mm SL.In this growth stanza, the fish develop free-swimming ability gradually, migrate into bays and concentrate in shallow waters.In the third growth stanza (16-32mm SL), relative growth is highly negative (the relative growth coefficients, a<<1) in these body parts and actually negative (a<0) in some of them indicating a fast decrease of these parts in proportion to the length of the fish.In this growth stanza the fish move into grass beds, and the transition from pelagic to demersal life is completed at the end of the stanza.Over 32 mm SL, relative growth is slightly negative and stable until 20 cm SL, the size limit of the observations.Stomach contents of demersal young fish caught in grass bed were analyzed and a flexible feeding strategy was demonstrated.The fish is seemingly a random feeder which utilizes the most abundant food items available from more than one microhabitat within grass beds.They take small fishes and crustaceans both at the sea bottom, on Zostera blades, and in the water column between Zostera blades.View full abstractDownload PDF (2857K) -
Shigeharu Kudo, Norihiko Kimura1984 Volume 30 Issue 4 Pages 393-403
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSGill epithelia of rainbow trout fingerlings suffering bacterial gill disease were examined by scanning electron microscopy.Surface ultrastructure of the outermost layer of epithelial cells in normal lamellar and filament epithelia was characterized by branching and anastomosing microridges approximately 275 nm in width, with average spacing of about 390 nm and considerably varying lengths.In hyperplastic lesions, little typical microridge structure was observed on the surface of the epithelial cells, instead shortened and thickened contours averaging 520 nm in width were seen along the longitudinal axis with many constrictions.Further, fine granular elements averaging 550 nm in size often appeared on the epithelial cell surface, piled one upon another or in bead-like chains which were frequently connected with short irregular microridges.
The free surface of normal chloride cells was generally characterized by a granular texture studded with short microvillus-like or isometric granular projections averaging 460 nm in thick-ness.Among these projections a small number of extremely short microridge structures frequently appeared.In bacterial gill disease, the microvillus-like projections were more numerous, denser and thinner than in healthy fingerlings;they averaged a thickness of 310 nm and exhibited several gourd-like constrictions implying plasma membrane vesiculation at their tips.Domed chloride cells were covered with either a number of small verruciform projections irregular in size and shape or a few thick and short projections.The latter surface was difficult to discriminate from the surface in the early stage of the globoid structure appearing on the gill lamellae.
The free surface of mucous cells in healthy fingerlings was rather smooth and often more prominent than other types of cells, but in diseased fingerlings many of mucous cells were domed and their surface was either smooth or had several small prominences which might have been caused by secretory granules underneath.View full abstractDownload PDF (21100K) -
Hiromi Ohta1984 Volume 30 Issue 4 Pages 404-411
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA large number of electron dense granules less than 2μm in diameter were found in granulosa cells in the pre-ovulatory follicles of the Pacific herring, Clupea pailasi, except in the region of the micropylar funnel where a micropylar cell and granulosa cells overlying the funnel were almost devoid of the granules.Granulosa cells in the post-ovulatory follicle had lost a large majority of cytoplasmic granules.On the chorion of ovulated eggs, a thin, electron dense layer newly occurred.This layer was sticky, and covered the whole surface of the chorion except for the micropylar region.These observations indicate that cytoplasmic granules existing in pre-ovulatory granulosa cells may be the origin of the adhesive material of the herring eggs.The micropylar region of ovulated eggs was, on the other hand, covered with two kinds of materials which seem to have been secreted from micropylar and granulosa cells covering the micropylar region.It is suggested that a micropylar cell and granulosa cells in the micropylar region are probably involved in the formation of material which may favor efficient fertilization of eggs in the herring.View full abstractDownload PDF (11738K) -
Tomokichi Kobayashi, Tetsuji Iwamoto1984 Volume 30 Issue 4 Pages 412-418
Published: February 15, 1984
Released on J-STAGE: July 04, 2011
JOURNAL FREE ACCESSEarly life history of the threebanded sweetlip, Plectorhynchus cinctus was studied from eggs, larvae and juveniles reared in the laboratory.Juveniles collected from the Suo Sea in the western region of the Seto Inland Sea were also studied.The artificial insemination was carried out in June and July and larvae were reared from June 25 to September 7 of 1981.
Eggs were 0.79 mm in diameter, pelagic, spherical with a single oil globule of 0.20 mm in diameter.Incubation time was 33-35.5 hours at the temperatures of 21.6-23.2°C.Length of prolarva 2 hours after hatching was 2.2 mm.By the time of yolk absorption in three days larvae grew to 2.9 mm.Transformation of larvae to the juvenile stage was completed at 9.1 mm.During early developmental stages, outstanding features included the formation of head armatures and dense pigmentation of body.Head armatures were acquired in the sequence of preopercular spines at 3.3 mm, supraorbital and upper cleithral spines at 5.5 mm, and postocular and subopercular spines at 9.1 mm.Several of these spines and the conical teeth in early juveniles were lost in the advanced specimen of 21.3 mm.In advanced larvae and juveniles melanophores were scattered over the entire surface of body except the upper parts of soft dorsal and anal fins, pectoral fin and caudal fin including caudal peduncle.This color pattern changed rapidly by physical stimuli from the uniformly black to the pale with distinct four oblique bands suggesting the potential differentiation of the typical color pattern in this species.A wild-caught juvenile, 50 mm in total length was provided with three oblique bands and several dots which were more distinct and fewer than those in the adults.In the fields, juveniles were found from early July to early August in the surf zone in the waters surveyed.View full abstractDownload PDF (3729K) -
Seiichi Mori1984 Volume 30 Issue 4 Pages 419-425
Published: February 15, 1984
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThree hundred and ninety five specimens of Gasterosteus aculeatus microcephalus were collected from the Yamayoke River and Tsuya River in the southwestern part of Gifu Prefecture and the Amano River in the northeastern part of Shiga Prefecture, Japan.Their morphometric and meristic characters were examined to study whether or not this species shows sexual dimorphism.
The number of anal fin rays showed a tendency to be larger in males than in females.Another marked sexual difference was found in the ratio of the head length to the body length: the pro-portional head length was clearly larger in males than in females.This dimorphism seemed to have occurred in relation to breeding habits.Males frequently use the head in fighting to guard their territory and in building nests.The larger head of males may make easy to do so.The ethological significance of the larger head of male is discussed.View full abstractDownload PDF (3228K) -
Shiro Fujita, Toshihisa Yogata1984 Volume 30 Issue 4 Pages 426-434
Published: February 15, 1984
Released on J-STAGE: February 23, 2011
JOURNAL FREE ACCESSThe present paper deals with ovarian maturation by hormone injection and morphological development of the amberjack, Seriola aureovittata Temminck et Schlegel.Ovarian maturation of the amberjack during the spawning season was successfully induced by injection of either “Gonatropin7” (Teikoku Zoki Mfg.Co.Ltd.), or Hypophthalmichthys molitix's pituitary homogenate, or H.molitrix's pituitary homogenate combined with “Gonatropin”.The last dosage was evaluated to be the most effective and reliable.The spawning period seemed to ex-tend from late April to the mid-May in the Sea of the Goto Islands.On May 14, 1977 the authors performed artificial fertilization of the specimens which were artificially induced to mature by the hormone injection, and reared the hatched larvae to grow to the juvenile stage.The eggs of the amberjack are pelagic, spherical in shape and 1.27-1.50mm in diameter.The yolk is roughly segmented and contains a single colorless oil globule of 0.34-0.36mm in diameter.The perivitelline space is narrow.During embryonic development, many melanophores and xantho-phores appear on the embryo and oil globule.Hatching took place in 96 hours after artificial fertilization at water temperatures between 15.5 and 20.4°C.The newly hatched larvae were 4.45-4.55mm TL and had 26 (12+14) myomeres.Characteristic features at the larvae were that the oil globule was situated at the anterior part of the segmented yolk which was extended slightly beyond the head and that the granules existed on the marginal fin which was densely pigmented with xanthophores.The yolk was almost all absorbed when the larvae attained 5.23-5.45mm TL, 4 days after hatching.In a 9-day old postlarva, 6.25mm TL, small denticles appeared on the margin of the upper jaw and there were 4 opercular spines on the preoperculum.In a postlarva 19-days after hatching, 7.5mm TL, the notochord was turned up and caudal, dorsal and anal fins with rudiments of rays were beginning to develop.In a 30-day old juvenile, 15mm TL, the coloration of the body was pale greyish black with the characteristic 2 yellow bands situated at the anterior part of the trunk and the caudal region.In a juvenile of 40-days, 23mm TL, 3 4 greenish dark brown cross bands appeared on the posterior part of the side of the body.The number of the bands increased to 7 at a size of 45mm TL, but such bands had disappeared in a specimen of 195mm TL.View full abstractDownload PDF (3718K) -
Toru Takita, Shin-ichi Kondo1984 Volume 30 Issue 4 Pages 435-443
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn Nagasaki Prefecture during 1981, larvae and juveniles of Allanetta bleekeri were collected from June to October with a larva net and dip net in Omura Bay, and immature individuals were collected under fish lamps in Nomo Harbor from April to December.Morphological development, local occurrence and food composition, especially in larval and juvenile stages, were studied.
A.bleekeri reaches the juvenile stage at sizes of 13.2-15.6mm in total length.The common morphological characteristics of other species of the Atherinidae were observed in larvae and juveniles.These include round head, short trunk, long and compressed tail, melanophore procession along the dorsal edge of the body, longitudinal black stripe formed laterally, fin fold remaining till early juvenile stage.The following points are important to distinguish larvae and juveniles of A.bleekeri from those of the other species of the same family, due to their supposedly sympatric occurrence: presence of melanophores on rear of notochord and caudal fin base, presence of ventral melanophore procession between pelvic and anal fins, and reach of lateral stripe.Relative growth during the early developmental stages is divided into three phases: larval, juvenile (up to 20-25mm in total length), and ault-form stage.
Larvae were collected with a larva net from the surface layer.They occurred abundantly from June to early September along the coast where Zostera marina or Sargassum spp.grew thick.Their occurrence is thought to have started in May.Larva net collection showed rather extensive distribution in the young larval stage.Well-grown larvae and juveniles were observed to form concentrated schools along the sea-wall of a harbor in September and October.
Investigation on food composition in digestive tracts revealed A.bleekeri to be a zoo-plankton feeder mainly relying on Copepoda and its larvae.View full abstractDownload PDF (1219K) -
Kiyoshi Fujita, Jin Hattori, Kiyoki Tsutsumi1984 Volume 30 Issue 4 Pages 444-447
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS -
Hajime Ishihara1984 Volume 30 Issue 4 Pages 448-451
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS -
Hajime Ishihara, Shuzo Kishida1984 Volume 30 Issue 4 Pages 452-454
Published: February 15, 1984
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS
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