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1.
S. Tanaka 《Limnology》2001,2(3):219-222
Three species of Ilyocryptus, Ilyocryptus sp., I. cuneatus Stifter 1988, and I. spinifer Herrick 1882, are newly recorded from the Japanese islands. The first two species were found separately at two sites in Hokkaido and the third at eight sites in Honshu and Kyushu. Their morphological features are briefly described based on parthenogenetic females. Received: May 21, 2001 / Accepted: July 23, 2001  相似文献   

2.
Upeneus australiae sp. nov. is described on the basis of 14 specimens collected from Australian waters. Although it belongs to the seven-spined group of Upeneus, now comprising five species, U. australiae is distinguished from its congeners by the combination of the following characters: 6–7 + 16–18 (modally 7 + 17) gill rakers, ectopterygoids without teeth, five and six black oblique bars on upper and lower caudal lobes, respectively, and peritoneum transparent with small black spots. Received: July 26, 2001 / Revised: November 2, 2001 / Accepted: December 4, 2001  相似文献   

3.
 A rare deep-sea ophidiid genus Mastigopterus known to contain two species, M. imperator Smith and Radcliffe, 1913 and M. praetor Smith and Radcliffe, 1913, was reviewed on the basis of six specimens including the holotypes of both species. Dorsal and anal fin ray counts and the size of cephalic sensory pores previously thought to be diagnostic characteristics to discriminate the two species did not suggest the presence of two forms, the large (M. imperator) and the small species (M. praetor), in the genus. Apparently the genus is represented by a single species, M. imperator, known from off Madagascar, the East and South China Seas and Papua New Guinea. Received: September 7, 1999 / Revised: July 9, 2001 / Accepted: November 13, 2001  相似文献   

4.
The Australian marine atherinid fish, Atherinomorus vaigiensis (Quoy and Gaimard, 1825), having long been synonymized under A. lacunosus (Forster in Bloch and Schneider, 1801), is redescribed as a valid species based on the holotype and non-type specimens. Atherinomorus vaigiensis, known only from eastern and western Australia, differs from other congeners in lacking a distinct tubercle on the posterior end of the dentary and having the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, 12–15 anal fin soft rays, 24–28 lower gill rakers, 39–42 midlateral scales, and a narrow midlateral band (width about 2/3 to 5/6 that of midlateral scale at level of anal fin origin). Atherina cylindrica Valenciennes in Cuvier and Valenciennes, 1835 and Pranesus ogilbyi Whitely, 1930 are regarded as junior synonyms of Atherinomorus vaigiensis. Received: April 26, 2001 / Revised: July 11, 2001 / Accepted: July 16, 2001  相似文献   

5.
To estimate the spawning site of the spotted flagtail, Kuhlia marginata, sperm motility was examined under conditions of different salinities. The spermatozoa were immotile in 0 and 5 ppt test solutions and in seminal fluid but lived longer in 20–30 ppt. Sperm were most active at 25–35 ppt. Therefore, we considered that spotted flagtail spawn in 20–35 ppt salinity. Because the mean salinity of the Genka estuary is below the optimum required for spawning, the spawning site in Okinawa Island would be seawater. This evidence suggested that the spotted flagtail is a catadromous species. Received: January 26, 2001 / Revised: July 6, 2001 / Accepted: July 24, 2001  相似文献   

6.
The phylogenetic relationships of all nine known tomato species of Solanum section Lycopersicum, together with other Solanum sections and species from several related genera, were investigated using parsimony analysis of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (rDNA). Most parsimonious reconstructions divided the section Lycopersicum into three clades, reflecting their mating behaviour and fruit colour. Data from sequencing studies were congruent with those from morphological and other molecular investigations, and provided detailed information concerning species relationships. Received: 11 July 2000 / Accepted: 17 April 2001  相似文献   

7.
Polydactylus konadaensis Mishra and Krishnan, 1993 was described on the basis of two specimens from Konada, Andhra Pradesh, east coast of India. Although the new species was placed in the genus Polydactylus, our examination of the type specimens of the species showed them to represent a species of Filimanus. Furthermore, the characters of those specimens were consistent with those of the lectotype, paralectotype, and other specimens of F. xanthonema (Valenciennes in Cuvier and Valenciennes, 1831). Accordingly, Polydactylus konadaensis is herein regarded as a junior synonym of F. xanthonema. Received: July 2, 2000 / Revised: November 2, 2000 / Accepted: January 12, 2001  相似文献   

8.
Seventy five accessions belonging to 14 species of the genus Cicer were analysed with PCR-based molecular markers to determine their phylogenetic relationships. Eight of the species were annuals and included the Section Monocicer which contains cultivated chickpea (Cicer arietinum L.). The remaining six species were perennials (five from Section Polycicer and one from Section Acanthocicer). More than one accession per species was analysed in most of the wild species; within C. arietinum, 26 accessions including Kabuli and Desi types, were studied. RAPD analyses using 12 primers gave 234 polymorphic fragments. Variability within species was detected. A dendrogram based on the Jaccard similarity index showed that the distribution pattern of variability between species was related to both growth habit and geographical origin. An accession of Cicer reticulatum was closer to accessions of Cicer echinospermum than to the four remaining of C. reticulatum, suggesting the possibility of gene flow between species. Cluster analysis for cultivated chickpea differentiated Kabuli and Desi types but we did not detect a clear relationship between groups and the geographical origin of the accessions. Received: 5 April 2001 / Accepted: 13 July 2001  相似文献   

9.
Diaphus theta is one of the most common myctophid fish species in the subarctic and transitional waters of the North Pacific. The growth of larval and juvenile D. theta was investigated using sagittal otolith increment analysis of specimens caught in transitional waters of the western North Pacific. Samples taken over a 24-h period demonstrated that otoliths exhibited daily growth cycles, allowing accurate determination of age. Calcification of the incremental zone of otoliths took place only at night, suggesting that the formation cycle of the increment of juvenile D. theta was different from that of shallow-water fishes and would be related to their diel vertical migration. The relationships between standard length (SL) and daily growth increment (D) were expressed as linear equations: SL = 2.65 + 0.141D (r 2 = 0.942) for larvae of 5.1–9.6 mm SL and SL = 3.54 + 0.129D (r 2 = 0.933) for juveniles of 13.7–27.6 mm SL. The growth rates were 0.14 mm d−1 in larvae and 0.13 mm d−1 in juveniles; this is slow compared with tropical or subtropical mycto-phid species, in which growth occurs at about twice these rates. The larval period, including the metamorphic stage, was long compared with species at lower latitudes and was estimated to be 71 days. The slow growth rate and long period of larval stage of D. theta would be the life history pattern of high-latitudinal species adapted to a low-temperature habitat. Received: March 23, 2001 / Revised: July 5, 2001 / Accepted: July 19, 2001  相似文献   

10.
Bifidobacteria play important roles in human health. However, the influence of exogenous factors on species composition of fecal bifidobacteria is still unclear. The objective of this study was to investigate the effects of fermented milk administration on the species composition of fecal bifidobacteria by molecular biological methods. Fermented milk containing Lactobacillus helveticus was given to seven healthy subjects, and the probiotic effect on human fecal microflora was demonstrated as a significant increase of bifidobacteria and decrease of clostridia by the conventional culture method. Species composition of bifidobacteria in the human fecal microflora was then investigated directly in fecal specimens by the PCR detection method. The species composition of bifidobacteria in the fecal specimens did not change significantly throughout the study period. These findings suggest that the species composition of bifidobacteria remains stable even when fecal microflora is improved by food management. Received: 12 July 2001 / Accepted: 14 September 2001  相似文献   

11.
A new acropomatid, Malakichthys barbatus, is described on the basis of 27 specimens (76.3–180.1 mm SL) collected from Suruga Bay to Tosa Bay, along the southern Pacific coast of Japan. The new species is unique in having numerous pairs of spines on the chin (a pair of spines in other congeners). Although the new species resembles M. elegans in having a slender body (the depth less than 35% SL), the former is further distinguishable from the latter in having a slender first proximal radial of the anal fin with no hollow (broad with a cone-shaped hollow in M. elegans), 43–48 lateral line scales (48–51), modally 21 gill rakers on the lower arm (modally 23), and a dark blotch on the opercle (no remarkable blotch). Received: July 2, 2000 / Revised: September 27, 2000 / Accepted: January 30, 2001  相似文献   

12.
A new genus and species of deep-sea zoarcid fish, Pyrolycus manusanus, is described on the basis of eight specimens collected from a hydrothermal vent field in the Manus Basin, Papua New Guinea, at depths of 1623–1971 m. This genus is distinguished from other scaleless eelpout genera in the subfamily Lycodinae by the following combination of characters: six suborbital bones; six to seven suborbital pores; flesh gelatinous; gill slit large, extending ventrally beyond pectoral fin base; three postorbital pores; single occipital pore; two to three pelvic fin rays; palatopterygoid series weak; vomer and palatine teeth present; pseudobranch, scales, lateral line absent; pyloric caeca present; 16–17 pectoral fin rays; 22–23 + 56–59 = 78–81 vertebrae. Received: August 5, 1999 / Revised: July 5, 2001 / Accepted: August 26, 2001  相似文献   

13.
Seventy-eight bacterial isolates from human, animal, and plant hosts, representing eight species of the family Enterobacteriaceae, were screened for F-like plasmid sequences. Of the examined human Escherichia coli strains, 28% harbored one or two of the three F-like, RepFI replication regions, while 35% of the examined animal and all phytopathogenic strains harbored RepFIA-specific sequences. Comparative analysis of Salmonella, Shigella, Erwinia, and E. coli plasmid RepFI sequences showed 100% or very high homology, indicating frequent and recent interspecies gene transfer. The high incidence of RepFIA sequences in enteric bacterial species, including Klebsiella and Erwinia, showed that F-like plasmids are successful in avoiding natural barriers to establishment of horizontally transferred DNA and that in the natural environment conjugal transfer is efficient in diverse ecological niches. Received: 26 March 2001 / Accepted 12 July 2001  相似文献   

14.
T. Oda  C. Tanaka  M. Tsuda 《Mycoscience》2002,43(4):0351-0355
 Two new species from Japan, Amanita areolata and Amanita griseoturcosa, are described. The former, found in a broad-leaved forest in Aichi Prefecture, is a medium- to large-sized mushroom characterized by an areolate, brownish pileus, a nonstriate and appendiculate margin of the pileus, and amyloid basidiospores. The latter, found in forests with Fagaceae or Pinaceae in Tokyo, Chiba Prefecture, and Miyagi Prefecture, is a medium-sized mushroom characterized by a grayish-turquoise pileus, a nonstriate margin of the pileus, a saccate volva, an apical membranous annulus, and amyloid basidiospores. Received: July 10, 2001 / Accepted: June 5, 2002  相似文献   

15.
The mating behavior of the rock catfish Silurus lithophilus (Siluriformes: Siluridae), a species endemic to the Lake Biwa system, was observed from May to July in 1989–1994 along the rocky shore of the lake's outlet, the Seta River. The mating behavior of S. lithophilus involved a certain behavioral sequence: “chasing,”“clinging,” and “enfolding” while “squeezing” by the male; and “circling” by the spawned pair. The mating behavior of this species was basically similar to that of S. biwaensis, but greatly different from that of S. asotus, which spawns in running water (in ditches). The mating behavior of S. lithophilus (and S. biwaensis) might have developed as an adaptation to lentic environments such as the shores of the large river or the lake. Received: October 25, 2000 / Revised: February 25, 2001 / Accepted: March 8, 2001  相似文献   

16.
The physical factor inducing spawning of the Biwa catfish, Silurus biwaensis (Siluriformes: Siluridae), an endemic species of Lake Biwa, was investigated on the basis of field observations on 150 nights at the spawning site, the rocky shore of the Seta River, the lake's outlet, and environmental data from April to July in 1989–1994. The catfish gathered at the spawning site when the water level of the river rapidly rose and the rocky shoal became submerged, within a wide range of water temperature (15.0°–30.0°C); their spawning was induced in relation to increases in the submerged portion of the rocky shoal. This observation suggests that water level control operations in Lake Biwa might critically affect the spawning of this and other fish species. Received: December 17, 1999 / Revised: September 13, 2000 / Accepted: January 16, 2001  相似文献   

17.
Polydactylus bifurcus sp. nov. is described on the basis of a single specimen collected from Lombok Island, Indonesia. The new species is distinguished from all other Indo-Pacific Polydactylus species by the following combination of characters: 15 pectoral fin rays, 5 pectoral filaments, 69 pored lateral line scales, 30 gill rakers, second spine of first dorsal fin very strong and lateral line bifurcated on caudal fin base, extending to posterior margins of upper and lower caudal fin lobes. Received: October 19, 2000 / Revised: April 21, 2001 / Accepted: April 25, 2001  相似文献   

18.
N. Maekawa  K. Hasebe 《Mycoscience》2002,43(3):0271-0275
Pseudolagarobasidium calcareum (Basidiomycotina, Corticiaceae s.l.) is newly reported for Japan, and its cultural characteristics are described for the first time. Seven of nine Japanese and Taiwanese specimens examined produce arthroconidia associated with the basidiomata. Variability in color of the hymenial surface is also observed among the specimens. In culture, this species is characterized by fiber hyphae (quasi-binding hyphae) and arthroconidia. Mating tests reveal a multiallelic, bifactorial incompatibility system of this fungus and intercompatibility between Japanese and Taiwanese strains. This species resembles Pseudolagarobasidium subvinosum but differs in producing the fiber hyphae not only in culture but also in the basidiomata. Received: July 10, 2001 / Accepted: March 29, 2002  相似文献   

19.
20.
Several previous studies have attempted to correlate habitat complexity and reef fish species diversity. These studies have mostly examined natural reef systems, but results differed. To examine this relation, we built 1 m2 habitats with 20 replicates of five complexity levels from July to August 2001 in the northeastern Gulf of Mexico (n=100). In June and July 2002, we built new habitats using the 2001 design, but also added a sixth complexity level (n=120). In order of increasing complexity these included: cage, shell, cage-shell, block-shell, cage-block-shell, and shell-block-pyramid habitats. Most fish in both years were juveniles and included species common to reef structures in the northeastern Gulf of Mexico. In 2001, we identified 26 fish species, and the dominant species was red snapper, Lutjanus campechanus (41%), followed by rock sea bass, Centropristis philadelphica (23%), and sand perch, Diplectrum spp. (14%). In 2002 we identified 36 species, and the dominant species was tomtate, Haemulon aurolineatum (36%), followed by Diplectrum spp. (19%), and L. campechanus (13%). In 2001, species diversity and richness were significantly (P<0.05) higher on more complex habitats (H′=1.7, S=11–12) compared to less complex habitats (H′=0.8–1.0, S=4–9). In 2002, patterns among diversity, richness and reef complexity were less apparent with only the least complex habitats shell and cage showing significantly lower values. In both years, multidimensional scaling grouped by complexity levels with cage and shell habitats showing the clearest separation from other habitat types. Also, with few exceptions (only 8%) analysis of similarities showed significant (P<0.05) differences in fish communities across complexity levels. Although community composition varied between years, this study provided evidence to support the hypothesis that habitat complexity increased reef fish species diversity.  相似文献   

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