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1.
A new triggerfish,Rhinecanthus abyssus, is described from three specimens collected in the Ryukyu Islands at depths of 120–150 m. It is distinguished from the other species ofRhine-canthus by the combination of the following characters: soft dorsal rays 22–23, soft anal rays 20, a large black blotch around anus, and no semicircular white band on posterior side of body.  相似文献   

2.
A new sparid Rhabdosargus niger is described on the basis of three type specimens collected from off Kalimantan, Indonesia. The species can be differentiated from all known congeners by the following combination of characters: dorsal-fin rays XI, 13, anal-fin rays III, 11, scale rows below lateral line 11½–12½, scale rows between the fifth dorsal-fin spine base and lateral line 5½, pored lateral-line scales 53–55, head and body silvery-black, pelvic and anal fins dusky gray, and no golden longitudinal lines on the body. Partial sequences of mitochondrial COI gene (571 bp) strongly supported the distinctiveness of R. niger within the genus. Taxonomic status of the nominal species synonymized under Rhabdosargus sarba (Forsskål 1775) is discussed and the key to the species of Rhabdosargus is provided.  相似文献   

3.
Marine fishes were collected from off the Maldive Islands in March, 2005. From amongst the material collected, the nematode Cucullanus maldivensis n. sp. is described from the intestine of a lutjanid fish, the black and white snapper Macolor niger (Forsskål). This species is morphologically and biometrically most similar to C. bourdini Petter &; Le Bel, 1992, differing from it principally in the protruding vulval lips, the location of the first pair of pre-anal papillae, the absence of an elevated cloacal region, and having distinctly larger eggs (51–57 × 33–36 μm). Additionally, adult females of the nematodes Procamallanus (Spirocamallanus) sp. and Camallanus sp. from the green jobfish Aprion virescens Valenciennes (Lutjanidae) and the rainbow runner Elegatis bipinnulata (Quoy &; Gaimard) (Carangidae), respectively, were collected. These camallanids are illustrated and measurements are provided, but they were not identified or described in detail as no males were collected.  相似文献   

4.
Arabibarbus hadhrami, a new species of cyprinid fish from the Hadhramaut Province of Yemen, is described. It has modally 30 scales (29–32) in the lateral line, the wedge-shaped head is longer (27.8–32.5 % SL) and higher (15.5–18.4 % SL) than in its congeners. The body is slender and laterally flattened. The dorsal fin is high (26.5–32.4 % SL) and well ossified. The pectoral fins (19.9–23.9 % SL) and pelvic fins (16.8–19.8 % SL) are longer than in its congeners. Two closely related species, Arabibarbus arabicus and Arabibarbus grypus are re-described and compared to the new species. Based on morphological and molecular characters the new genus Arabibarbus is erected for these three species. It is characterised by medium to large body size, an ossified, smooth principal dorsal fin ray, eight branched dorsal and five branched anal fin rays, large shield-shaped scales with numerous parallel radii, a lateral line with 29 to 44 scales, pharyngeal teeth that are hooked at their tips, their count being 2.3.5–5.3.2 and the possession of two pairs of barbels. Arabibarbus hadhrami is the type species of the new genus. The phylogenetic position of the new genus is analysed, based on the mitochondrial cytochrome b gene. It is the sister taxon to the genus Carasobarbus Karaman, 1971 and closely related to Mesopotamichthys Karaman, 1971, Pterocapoeta Günther, 1902 and ‘Barbusreinii Günther, 1874. Arabibarbus probably colonised the Arabian Peninsula about 4 Ma ago, coming from the Tigris-Euphrates drainage in the East via Wādī ar Rimah/Wādī al Bā?in.  相似文献   

5.
A new subspecies of the ayu,Plecoglossus altivelis ryukyucnsis, is described on the basis of specimens from Amami-oshima and Okinawa Islands, the Ryukyu Islands, Japan. This new subspecies is distinguished fromP. altivelis altivelis by the fewer numbers of pectoral fin rays, longitudinal scales and scales above and below the lateral line, and also by the unique electrophoretic mobilities of several enzymes.  相似文献   

6.
The phylogenetic relationships among five species of sculpins, including Myoxocephalus stelleri, M. brantii, M. jaok, M. ochotensis, and Megalocottus platycephalus, were estimated from the sequence variability of the mtDNA cytochrome b (cytb) and cytochrome oxidase 1 (CO1) genes. Analysis of the topologies of combined phylogenetic trees showed that all of the morphologically described species from different genera represented monophyletic groups with high support of branch robustness. Haplotypes with different karyotypes from different geographical localities with an intragroup nucleotide diversity of 0.42% were combined into the M. stelleri clade. All of the species (except for M. stelleri from the Sea of Japan and the Okhotsk Sea coast of the Hokkaido Island) were characterized by relatively low values of the intragroup variation, along with high values of interspecific variation of mtDNA-encoded markers. Studies of the M. stelleri karyotypes using Ag-banding showed that karyotypes of the individuals from the Sea of Japan and Okhotsk differed not only in the number of chromosomes (2n) but also in the number of active nucleolus organizers (NO) and stained NO blocks, calling into question whether they belong to a single species. The observed discrepancy between the phylogenetic topologies and karyological data is discussed in relation to the informative capacity of mtDNA fragments and the phenomenon of intraspecific chromosomal polymorphism.  相似文献   

7.
Investigations were made on the effect of species of fungi isolated from therhizosphere of broad bean (Vicia faba Linn.) variety Giza I, and cotton (Gossypium barbadense Linn.) variety Giza 47, on plant growth. Broad bean rhizosphere fungi differently affected plant growth.Fusarium moniliforme, Penicillium martensii, Rhizopus stolonifer, andCladosporium sphaerospermum stimulated both root and shoot growth.Aspergillus niger andAlternaria tenuis have an inhibitory effect on plant growth. On the other hand, the rhizosphere fungi of cotton namely,Penicillium cyclopium, Aspergillus terreus, Cephalosporium sp.,Aspergillus niger, Cladosporium sphaerospermum, andFusarium oxysporum stimulated plant growth.  相似文献   

8.
Studies were conducted to determine the effect of insecticide residues on germination of primary conidia ofentomophthora muscae (Cohn) Fresenius and to determine the relative susceptibility of healthy and infectedMusca domestica L. to insecticides. Primary conidia were discharged fromM. domestica cadavers onto glass microscope slides treated with insecticides. All insecticides significantly inhibited germination relative to control slides. Permethrin and naled had the least inhibition (36–40 %), while malathion and dimethoate almost completely inhibited germination (87–94 %). Tetrachlorvinphos/dichlorvos and carbaryl were intermediate (57–59 %). Healthy flies were not significantly different from infected flies in terms of susceptibility to naled, dimethoate, or permethrin. Infected flies exposed on the last day of pathogen incubation died on the bottom of the Petri dishes, rather than climbing and attaching as did untreated, infected flies. Both control and treated groups produced large numbers of primary conidia.  相似文献   

9.
This study provides first insights into the energetics of the Nesomyinae, a subfamily of rodents endemic to Madagascar. The ancestral nesomyine colonized Madagascar from Africa ca. 30–15 mya at the onset of Oligocene global cooling. We tested the hypothesis that, contrary to what might be expected from Island Biogeography theory, post-colonization character displacement of thermoregulatory traits was constrained by phylogenetic inertia through climate adaptation. The study was conducted in the Parc National d’Ankarafantsika, Madagascar. We measured the basal metabolic rate (BMR) and body temperature (T b) patterns of naturally warm-acclimated, freshly captured adult long-tailed big-footed mice Macrotarsomys ingens (67.4 g). The mean ± SD BMR of M. ingens was 0.298 ± 0.032 Watts (n = 12), 31.7 % lower than that predicted by a phylogenetically independent allometric equation. Body mass was correlated with BMR. The lower critical limit of thermoneutrality (T lc) was 30.7 °C. The mean ± SD T b = 36.1 ± 0.8 °C (n = 12) compared well with the mean T b values for myomorph rodents from the Afrotropical zone, but was lower than those of the Neotropical and Palearctic zones. M. ingens became pathologically hypothermic when exposed to ambient temperatures lower than 18 °C. The soil temperature at depths of 250 mm and deeper did not decrease below 22 °C throughout the austral winter. The thermoregulatory data for M. ingens did not differ from those that characterize mainland Afrotropical rodents. However, BMR and T b were lower than those of Holarctic rodents. Thus, contrary to expectations of Island Biogeography theory that rapid character displacement often occurs in morphological and behavioural traits when mammals colonize islands, M. ingens displayed climate-related physiological traits indicative of phylogenetic inertia. Presumably the tropical conditions that prevailed on Madagascar at the time of colonisation differed very little from those of the African mainland, and hence there was no strong driving force for change. Unlike small tenrecs and lemurs that radiated on Madagascar prior to the Oligocene, traits associated with an insular existence, such as daily torpor and hibernation, were not evident in M. ingens.  相似文献   

10.
Applications of various amounts of GA3 onto the shoot apex of biennial rosette-plantHyoscyamus niger L., exposed to long days and non vernalized, caused internodes formation and stem elongation. The stem length was proportional to the amount of GA3 applied. Number and length of developed internodes and the whole length of the shoot were maximal in plants treated with a greater amount of GA3. In the end, stem elongation stopped and plants formed perchedrosettes without flowering. Hence, gibberellic acid participates in mechanisms of flowering only by indirect effect on stem elongation and not directly on flower formation itself.  相似文献   

11.
The chitin structures of two common European species belonging to Insecta (Melolontha melolontha) and Crustacea (Oniscus asellus) were isolated. The same procedure is followed for chitin isolations for both the species. First, HCl was used for removing of minerals in the organisms, and then, the protein structure was removed by using NaOH. Chitins obtained from these two species were characterized physicochemically. Physicochemical properties of chitins isolated from the insect and the crustacean were compared to each other. The chitin content for dry weights of M. melolontha and O. asellus were recorded as 13–14 and 6–7 %, respectively. The results of Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray diffraction analysis were found to be more or less similar. The surface morphologies of chitins were examined via environmental scanning electron microscopy and nanofibers, and pore structures were observed. While the chitin nanofibers of O. asellus were adherent to each other, nanofibers of M. melolontha were non-adherent. On the other hand, the number of pores was much higher in the chitin from M. melolontha than in the chitin from O. asellus. Looking at the elemental analysis results, the M. melolontha chitin was found to be more pure than the O. asellus chitin. For this reason, M. melolontha has been considered more attractive source for chitin than O. asellus.  相似文献   

12.
Dendropoma maximum is a vermetid gastropod (a sessile tube-forming snail) commonly associated with living corals throughout shallow-water reefs of the Indo-Pacific. Recent work suggests that, once established, this species can adversely affect growth and survival of corals. Here, we test the hypotheses that disturbances to live coral substrates (e.g., creation of bare patches) facilitate successful larval settlement and subsequent population growth of D. maximum, and conversely, that live coral inhibits D. maximum settlement. In the shallow lagoon of Moorea, French Polynesia, we selected patch reefs where D. maximum was either present or absent (to evaluate potential effects of resident adult conspecifics on recruitment) and established focal quadrats on each reef. In each quadrat, we either experimentally removed 50 % of live coral cover or left the quadrat with 100 % live coral cover. In addition, we deployed units of bare substrate (coral rubble) to each reef. We conducted a census of deployed substrates and quadrats after 6 months and found that D. maximum settled irrespective of resident vermetid populations, and only onto nonliving surfaces (i.e., cleared patches in quadrats, coral rubble, and marine epoxy). In laboratory experiments, we exposed larvae of D. maximum to live coral and found species-specific effects on survival of D. maximum larvae. Porites lobata and Pocillopora sp. killed larvae of D. maximum, Porites rus caused weaker mortality, and Millepora sp. had no effect on larval survival. Collectively, these results suggest that D. maximum requires disturbances that create bare patches to successfully settle onto reefs, and that a high cover of living corals contributes resilience to reefs by limiting settlement opportunities of a species known to reduce coral growth and survival.  相似文献   

13.
Three new species of the sciaenid genusAtrobucca are described:A. kyushini from off Borneo, differs from all known congeners in having no swimbladder appendages enveloplng the bladder, no forward directed branches from the ventral limbs of the appendages, a long tube-like last appendage parallel to the bladder wall and a pale mouth lining;A. brevis from off northern Australia and Papua New Guinea, is distinguished by its short pectoral fin (less than 23% SL) and pleural rib on the 11th vertebra;A. adusta from Papua New Guinea, is distinctive in having a low dorsal soft ray number (23–24) and long caudal peduncle (27–30% SL).Atrobucca Chu, Lo et Wu is redefined to accommodate the new species: the genus is principally characterized by the swimbladder appendages divided into developed dorsal and ventral limbs, and the only slightly curved sulcus tail of the sagitta. A key and diagnoses are provided for all known species ofAtrobucca.  相似文献   

14.
This study examined the effects of colony size and polyp position on six variables of polyp fecundity [egg number, egg size, total egg volume, total testis volume, total gonad volume, and gonad ratio (egg volume/testis volume)] in three tabular Acropora corals (Scleractinia), A. hyacinthus, A. japonica, and A. solitaryensis. Samples were collected from various colony sizes (n = 21–30 colonies species?1), just before the predicted spawning at Kochi, Japan, in 2009. Five replicate polyps were sampled at three positions (center, middle, and outer) from the center to the marginal area in each tabular colony. Results indicated effects of colony size and polyp position on both male and female gonads polyp?1. A positive effect of colony size was observed on variables of female gonads polyp?1 (egg number, total egg volume) in A. hyacinthus only, while the positive effect on the variable of male gonads polyp?1 (total testis volume) was common in all Acropora species, with total testis volume polyp?1 increasing 2–4-fold from the small (200–400 cm2) to the large size class (5,000–9,000 cm2). Among the polyp positions, lower values were observed mostly in center polyps in A. hyacinthus, while lower values were observed only in outer polyps in the other Acropora species. The distinct patterns between A. hyacinthus and the other two Acropora species suggest different reproductive strategies at the species level. Further studies are needed to confirm the prevalence of these effects in scleractinian corals, which will broaden our understanding of reproductive life history strategies and improve the estimation of reproductive performance.  相似文献   

15.
16.
The Mongolian racerunner (Eremias argus) is a small lacertid lizard species, and its distribution range encompasses the Korean Peninsula, Mongolia, China and Russia. Eremias argus is widespread, but populations on the Korean Peninsula are small and declining, provoking concerns that genetic diversity is being lost. This species is currently listed under the Protection of Wild Fauna and Flora Act in South Korea. In this study, nine novel microsatellites for E. argus were developed with a biotin-enrichment method and used to understand its population genetic structure and delineate conservation units on the Korean Peninsula. Overall, low intrapopulation genetic diversity was observed (mean number of alleles per locus = 2.463; mean H E = 0.398) from 10 populations investigated (n = 110). Two populations (among five with n≥ 10) showed an excess of heterozygosity expected under HWE relative to that expected at mutation-drift equilibrium, indicating severe reduction in population sizes. With only a few exceptions, the overall genetic differentiation among populations was substantial with the high levels of pairwise-F ST (0.006–0.746) and -R ST (0.034–0.940) values. The results of Bayesian STRUCTURE analysis showed that E. argus populations on the Korean Peninsula were most likely partitioned into three genetic clusters. Taken all together, such low levels of gene flow and strong genetic structuring have critical implications for the conservation of this endangered species and its management.  相似文献   

17.
A new holomorphic species, Mariannaea dimorpha, is described and illustrated. The verticillate conidiophores, phialidic conidiogenous cells and aseptate microconidia that form imbricate chains indicate that it belongs to the genus Mariannaea. Sequence analyses of the combined internal transcribed spacer (ITS) and partial large subunit ribosomal DNA (28S rDNA) confirmed its taxonomic position and revealed its distinction from any morphologically similar species. In addition, the teleomorph of M. samuelsii is reported for the first time and its epitype is designated.  相似文献   

18.
The species of the genus Macrosaldula Southwood et Leston of the fauna of Russia and adjacent countries are reviewed. Fifteen species and one subspecies are distributed in the investigated territory (among these, eight species marked with an asterisk occur in Russia): M. clavalis Cobben, *M. jakovleffi Reut., M. kaszabi Hob., M. kerzhneri Cobben, M. koktshetavica Cobben, *M. koreana Kir., M. nivalis Lindb., *M. oblonga oblonga Stål, M. oblonga acetabularis Cobben, M. mongolica Kir., *M. rivularia J. Sahlb., *M. simulans Cobben, *M. scotica Curt., M. tadzhika Kir., *M. variabilis H.-S., and *M. violacea Cobben. An illustrated key to the species and dotted distribution maps are given.  相似文献   

19.
A combined chemometrics-metabolomics approach [excitation–emission matrix (EEM) fluorescence spectroscopy, nuclear magnetic resonance (NMR) and high performance liquid chromatography–mass spectrometry (HPLC–MS)] was used to analyse the rhizodeposition of the tritrophic system: tomato, the plant-parasitic nematode Meloidogyne javanica and the nematode-egg parasitic fungus Pochonia chlamydosporia. Exudates from M. javanica roots were sampled at root penetration (early) and gall development (late). EMM indicated that late root exudates from M. javanica treatments contained more aromatic amino acid compounds than the rest (control, P. chlamydosporia or P. chlamydosporia and M. javanica). 1H NMR showed that organic acids (acetate, lactate, malate, succinate and formic acid) and one unassigned aromatic compound (peak no. 22) were the most relevant metabolites in root exudates. Robust principal component analysis (PCA) grouped early exudates for nematode (PC1) or fungus presence (PC3). PCA found (PC1, 73.31 %) increased acetate and reduced lactate and an unassigned peak no. 22 characteristic of M. javanica root exudates resulting from nematode invasion and feeding. An increase of peak no. 22 (PC3, 4.82 %) characteristic of P. chlamydosporia exudates could be a plant “primer” defence. In late ones in PC3 (8.73 %) the presence of the nematode grouped the samples. HPLC–MS determined rhizosphere fingerprints of 16 (early) and 25 (late exudates) m/z signals, respectively. Late signals were exclusive from M. javanica exudates confirming EEM and 1H NMR results. A 235 m/z signal reduced in M. javanica root exudates (early and late) could be a repressed plant defense. This metabolomic approach and other rhizosphere -omics studies could help to improve plant growth and reduce nematode damage sustainably.  相似文献   

20.
The two-spotted spider mite Tetranychus urticae is an important pest of strawberry crops in Brazil and many other countries. Focus for biocontrol studies involving entomopathogenic fungi has been on three species from the genus Metarhizium: M. anisopliae sensu stricto (s.s.), M. brunneum and M. robertsii. Also, the species Beauveria bassiana has been studied for spider mite control and one isolate (ESALQPL63) is commercially available in Brazil. New and undescribed Metarhizium species have been found recently in Brazil and provide a pool of isolates with potential for biocontrol in Brazil and probably also elsewhere. The mortality of adult females of T. urticae when exposed to four new Brazilian species of Metarhizium was compared to the mortality when exposed to M. anisopliae s.s., M. brunneum, M. pingshaense, M. robertsii and Beauveria bassiana ESALQPL63. Fungal suspensions were sprayed onto mites at 107 conidia/mL with 0.05% Tween 80 in laboratory bio-assays. We measured total mortality and percentage sporulating cadavers 10 days after exposure and calculated median lethal time (LT50). The lowest LT50 (4.0 ± 0.17) was observed for mites treated with Metarhizium sp. Indet. 1 (ESALQ1638), which also performed well with respect to mortality after 10 days and capacity to sporulate from cadavers. Among the other little studied species tested, M. pingshaense (ESALQ3069 and ESALQ3222) and Metarhizium Indet. 2 (ESALQ1476) performed well and were comparable to B. bassiana (ESALQPL63). The new Metarhizium isolates and species thus showed potential for biological control.  相似文献   

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