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Volume 36, Issue 4
Displaying 1-15 of 15 articles from this issue
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Kenji Mochizuki, Fumio Ohe1990 Volume 36 Issue 4 Pages 385-390
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSTwo specimens of the peculiar squalid shark, Trigonognathus kabeyai gen. et sp.nov., were collected from the coastal waters of Wakayama and Tokushima, Japan, by bottom trawl at depths of 330 and 360meters. Shape of teeth similar in both jaws; slender, unicuspid, canine-like, without any cusplets or serrations, with weak thin fold on both lingual and labial sides in anterior teeth on both jaws; tooth at symphysis of each jaw longest. Interspace between teeth very wide. Both jaws triangular in shape. Most of dermal denticles on body and head roughly rhombic, swollen very much near central part, with about 10-40 facets on the dorsal surface of its crown. Preoral snout length very short. Many small organs considered to be photophores present mainly on ventral surfaces of head and body.View full abstractDownload PDF (5384K) -
Shigeru Shirai, Kazuhiro Nakaya1990 Volume 36 Issue 4 Pages 391-398
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA new etmopterine species, Centroscyllium excelsum, is described from 21 adult specimens captured in the Emperor Seamount Chain, central North Pacific. The present species is distinguished from its congeners in having a very high and semicircular-shaped 1st dorsal fin with a developed spine, dermal denticles only on dorsal side of head and trunk, the 2nd dorsal spine arising behind pelvic fin base, a short caudal peduncle, and prefrontal wall and chondrified eye stalk on neurocranium. Ten embryos were collected from one of the female specimens, and some embryonic features are also noted.View full abstractDownload PDF (1413K) -
John E. Randall, Masayoshi Hayashi1990 Volume 36 Issue 4 Pages 399-403
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSA new species of cardinalfish, Apogon selas, is described from 27 specimens from New Guinea, Ryukyu Islands, and Philippines; also known from photographs taken in the Solomon Islands and Indonesia. It is a species of the subgenus Ostorhinchus Lacepède, distinctive in having a first dorsal fin of VII spines, 13 pectoral rays, 14-19gill rakers, smooth preopercular ridge, body depth 2.9-3.6in SL, and a color pattern of a black spot as large as the eye centered on the caudalfin base and two dusky stripes (mainly red or golden in life), one midlateral and the other from tip of lower jaw across cheek to thorax. A.selas appears to be most closely related to A.endekataenia Bleeker which differs in having 14 pectoral rays, 18-21 gillrakers, and six dark stripes on the body.View full abstractDownload PDF (1223K) -
Ronald Fricke1990 Volume 36 Issue 4 Pages 404-409
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSPsychrolutes occidentalis, a new species of psychrolutid fish, is described from mud bottoms at depths of 350-740m on the continental slopes around Rowley Shoals, northwestern Australia. The new species is illustrated and compared with other species of the genus Psychrolutes. It differs from other species in the following characters: 14-15 dorsal soft rays, 21-23 pectoral rays, 30-31 vertebrae, no cirri on head and body, lateral line not emerging through tubes, and reddish brown head and body color with darker brown marblings. Aspects of the zoogeography of this new species from the tropical region and of the other species of Psychrolutes are discussed.View full abstractDownload PDF (769K) -
Bryan E. Pierce, Keith B. Pierson1990 Volume 36 Issue 4 Pages 410-418
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSGrowth and reproduction of tidepool sculpins (Oligocottus maculosus) from three sites in Puget Sound, Washington State, USA were characterized. One site was a sandy, gently sloping beach, the second was an exposed rock headland with minimal algal cover, and the third was an exposed rock headland with numerous tidepools containing abundant algal cover. Length-weight relationships for sculpins did not differ significantly between sexes within sites. Population age structure, growth rate and recruitment varied among the three study sites using data pooled across both sexes. Young-of-the-year sculpins comprised 91% of the population at the exposed headland site with minimal algal cover but only 6% at the headland with abundant algal cover. Selective predation by great blue herons (Ardea herodias) upon tidepool sculpins larger than 45mm total length assisted in the maintainance of these age structures. A maximum gonadosomatic index of 28.5 was calculated; this index correlated poorly with either age, length or somatic weight. Diameters of unshed ova from preserved tidepool sculpins sampled prior to spawning fell into three classes. Comparison of the mean egg size of each mode and the number of modes present in preserved sculpins with similar data from tidepool sculpins that spawned in the laboratory suggested that spawning occurred twice yearly from at least January through August.View full abstractDownload PDF (1389K) -
Midoriko Kasama, Hiromu Kobayasi1990 Volume 36 Issue 4 Pages 419-426
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSHybrids from an intergeneric cross between Carassius carassius _??_×Gnathopogon elongatus elongatus _??_ were analyzed morphologically and karyologically and compared with the parental species. These hybrids possessed a mosaic of character expressions, but could be generally classified in two types similar to either C. carassius or G. elongatus elongatus. The karyotype was composed of two genomes of the Carassius parent and one of the Gnathopogon parent for the Carassius-type hybrids, and one genome of the Carassius parent and two genomes of the Gnathopogon parent for the Gnathopogon-type hybrids.View full abstractDownload PDF (7212K) -
Arun Kumar Sinha, Indrajit Singh, B. R. Singh1990 Volume 36 Issue 4 Pages 427-431
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSIn the sisorid fish, Glyptothorax pectinopterus, the adhesive organ located on the ventral side of the thorax consists of a number of longitudinal ridges and grooves that alternate with each other around a triangular furrow lying in the centre. Adhesion of the fish to the rocky substratum in a hill stream habitat is brought about by the hooked and keratinized epidermal spines borne by the longitudinal ridges of the adhesive organ as well as those on the under surface of the pectoral and pelvic fins. The secretion of a surface coat of mucopolysaccharides by the mucous cells and the goblet cells is a device to protect the adhesive organ from mechanical abrasion.View full abstractDownload PDF (4626K) -
Shunya Oka, Yoshiharu Honma, Toshihiko Iwanaga, Tsuneo Fujita1990 Volume 36 Issue 4 Pages 432-438
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSThis paper is concerned with part of the role and function of the caudal neurosecretory system of the charr, Salvelinus leucomaenis, studied by immunohistochemistry. In order to elucidate the different histologic changes, we examined the immunoreactivities of urotenisn I (UI) and urotensin II (UII) in 3 experimental groups: the feral (river) fish, the fresh-water aquarium-, and sea water aquarium-retained fish. Coexistence of UI and UII was demonstrated in most of the smaller and larger neurons distributed in and near the urophyseal system of all 3 groups. However, some of the larger neurons were immunoreactive only to a single hormone, UI or UII. Merely a few neurons indicated no reactivity for either UI or UII. No such clearcut differences were encountered immunohistochemically in the 3 groups. Neuronal and urophysial immunoreactivity to UI of feral and fresh-water-retained fish was slightly stronger than that of sea water-retained fish. Moreover, in sea water-retained fish, the intensity of immunoreactivity for UI was variable, and the number of neurons positive for UII only was somewhat larger than that in feral and fresh-water-retained fish. A series of UII-positive cerebrospinal fluid (CSF)-contacting neurons were seen in the ependymal and subependymal layers ventral to the central canal of the spinal cord in every group.These CSF-contacting neurons might constitute another neurosecretory system aside from the ordinary caudal neurosecretory system equipped with urophysis. In contrast to the hypothalamohypophysial neurosecretory system, the caudal neurosecretory system did not show any significant changes among the 3 groups. This suggests that urotensins I and II have no essential role in osmoregulation of the charr.View full abstractDownload PDF (8831K) -
Terry J. Donaldson1990 Volume 36 Issue 4 Pages 439-458
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSTen species of Pacific hawkfishes occur in small social groups consisting of a single male and one or more females. Facultative monogamy occurred regularly in two obligate coral dwelling species while the remaining species were largely haremic. Males had larger body sizes than females within groups but not necessarily between groups. Males defended territories in which females had home areas. Females defended courtship sites within a male's territory against neighboring females of the same social group.Courtship was paired and sequential within groups, commencing just prior to or after sunset and concluding at dusk. Spawning, when observed, was pelagic.View full abstractDownload PDF (16015K) -
Jack T. Moyer1990 Volume 36 Issue 4 Pages 459-467
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSChaetodontoplus mesoleucus occurs at Bantayan Island in a habitat of small patches of mixed scleractinian and alcyonacean corals of low diversity and simple structure. Male-female pairs were predominant, and the sex-ratio showed only a slight skew towards females. However, the presence of single male, two-female social groups demonstrates that the species is polygamous. Small size of social groups is attributed to a preference for a habitat lacking structural complexity. The species did not occur on complex coral reefs. Social and spawning behavior are nearly identical to that of most pomacanthids for which data are available, and although sex-change was not demonstrated, size-related dominance hierarchies and close phylogenetic relationships to sex-changing pomacanthids suggest protogynous hermaphroditism in this species. Behaviorally, C. mesoleucus appears quite similar to a large group of species proposed herein to represent a generalized pomacanthid behavioral type. Divergences from this generalized type by members of Genicanthus, eastern Pacific Holacanthus, and western Atlantic Pomacanthus are discussed. Evidence is given to suggest the phylogenetic derivation of the subgenus Centropyge (genus Centropyge) from an ancestor of the subgenus Xiphipops type. Color dimorphism and “rendezvous sites” are briefly discussed.View full abstractDownload PDF (1358K) -
Shigeru Nakano, Makoto Nagoshi1990 Volume 36 Issue 4 Pages 468-476
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSBrood defence of a cichlid fish, Lamprologus toae, was investigated in its natural habitat in Lake Tanganyika. Both parents guarding a brood attacked both conspecific and heterospecific intruder fishes at different locations. The heterospecific intruder fishes could be classified into three groups on the basis of the locations at which the attacks against each species took place. The distinction of groups by the parents seemed to be primarily based on food habits and feeding behaviour of the intruder fishes. The piscivorous species which were more dangerous for the brood were attacked by both parents at more distant locations from the brood. Parental defence of breeding territory changed with the development of the young. The frequency of attacks against each group decreased after the young reached the size too large for the fishes of the group to prey on. Division of labour in the territorial defence was recognized between male and female. The male parent mainly defended the peripheral region of the territory and the female parent defended the inner region. Significance of the selective attack against intruders and the division of labour between the two sexes in brood defence is discussed.View full abstractDownload PDF (1283K) -
Hmoud Fares Alkahem, R.J. Behnke, Zubair Ahmad1990 Volume 36 Issue 4 Pages 477-482
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS -
Wichian Magtoon, Ryoichi Arai1990 Volume 36 Issue 4 Pages 483-487
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS -
an Effective Mechanism for Position MaintenanceAldo S. Steffe1990 Volume 36 Issue 4 Pages 488-491
Published: March 05, 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESS -
1990 Volume 36 Issue 4 Pages 507
Published: 1990
Released on J-STAGE: June 28, 2010
JOURNAL FREE ACCESSDownload PDF (72K)
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