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1.
The type specimens of platycephalid Platycephalus endrachtensis Quoy and Gaimard 1825 are regarded as being conspecific with Platycephalus arenarius Ramsay and Ogilby 1886, so the latter becomes a junior synonym. This species is characterized as having a caudal fin with four or more longitudinal dark bands and lacking a yellow blotch. It is also found that Platycephalus westraliae (Whitley 1938), which had been considered to be a junior synonym of Platycephalus bassensis Cuvier 1829, is a valid species. Specimens that recently had been mistakenly identified as “P. endrachtensis,” having the caudal fin with three or four longitudinal dark bands and a yellow blotch on the upper lobe, should be referred to P. westraliae.  相似文献   

2.
New lobe development and lobe division was studied in the foliose lichen Xanthoparmelia conspersa (Ehrh. ex. Ach.) Hale. In thalli with either the centre or margin removed, the inside edge of the perimeter, the outer edge of the reproductive centre, and fragments derived from the thallus perimeter all regenerated growing points (‘lobe primordia’) within a year. Thalli possessing isidia had the greatest ability to regenerate growing points. In reproductive thalli, there was a positive correlation between the density of new growing points and thallus size. When fragments were cut from the perimeters of mature X. conspersa thalli and glued to pieces of slate, the ratio of growing points to mature lobes increased over 54 months. Lobes within a thallus exhibited different degrees of bifurcation. In some bifurcating lobes, the point of origin of the bifurcation advanced at the same rate as the lobe tips over 4 months but in most lobes, the bifurcation point either advanced less rapidly than the lobe tips or retreated from its original location. Removing adjacent lobes had no significant effect on the radial growth of a lobe over 4 months or on the location of the bifurcation point but it increased the number of growing points. These results suggest that for X. conspersa: 1) all portions of of thalli can regenerate growing points, 2) few growing points actually develop into mature lobes, 3) individual lobes within a thallus grow and divide differently, and 4) adjacent lobes inhibit the development of growing points on their neighbours.  相似文献   

3.
 This study redescribes Bregmaceros mcclellandi Thompson, 1840, based on one specimen (74.4 mm SL) from the Bay of Bengal and 66 specimens (30.0–84.7 mm SL) from Mumbai (Bombay), India, because the type specimens have apparently been lost. The present specimens are characterized by having black dorsal, pectoral, and caudal fins and show the following morphology: caudal fin slightly forked; body chromatophores present mainly at the dorsal part; no scales on cheek; vertebrae 52–55 (13–15 + 38–41); dorsal rays 52–59; anal rays 54–60; pectoral rays 18–20; caudal rays 27–31 (principal rays 14); transverse scales 14–15. In the 66 Mumbai specimens, it was confirmed that the distinctive black fin pigmentation developed sequentially with growth, with complete pigmentation first on the anterior lobe of the dorsal fin, then simultaneously on the posterior lobe of the dorsal fin, the caudal fin, and the pectoral fin, and last, on the anal fin. This species is known only from the Arabian Sea, Bay of Bengal, and Gulf of Thailand. A review of 16 nominal Bregmaceros species indicates that, besides B. mcclellandi, the distinctive dark fin pigmentation is found in B. atripinnis (Tickell), B. atlanticus Goode and Bean, B. japonicus Tanaka, and B. lanceolatus Shen. B. atripinnis is considered a junior synonym of B. mcclellandi, and the others are clearly distinct from B. mcclellandi. Comments are made on some of the characters to more fully characterize the species and for reference in future revisionary and phylogenetic studies. Received: June 17, 2002 / Revised: December 2, 2002 / Accepted: December 24, 2002  相似文献   

4.
 The external morphology, osteology, and myology of the African fluvial genus Teleogramma are described, and its familial allocation is discussed. Teleogramma is included in the family Cichlidae by loss of a major structural association between adductor mandibulae sections 2 and w, and by having an insertion of a large ventral division of adductor mandibulae section 2 onto the anguloarticular, expanded head of the fourth epibranchial, transversus dorsalis subdivided into four parts, functionally decoupled premaxillae and maxillae, the stomach's extendible blind pouch, the left-hand exit to the anterior intestine, the first intestinal loop at the left side, two epurals, seven branched rays on each upper and lower caudal fin lobe, free first uroneural from a united element of first preural and ural vertebra, and third preural vertebra fused with its haemal spine. Seven synapomorphies supporting the monophyly of Teleogramma are indicated, including the absence of or very low supraoccipital crest, the presence of a nostril tube, nonextended supraoccipital anteriorly, absence of extensive cartilaginous cap on the anterior border of the second epibranchial, presence of a beaklike projection on the cleithrum, caudal branched slip of epaxialis that inserts onto the upper two or three branched rays on the upper lobe of the caudal fin, and flexor dorsalis superior, which inserts onto the lower four unbranched rays on the upper lobe of the caudal fin. Received: September 12, 2001 / Revised: December 17, 2001 / Accepted: December 28, 2001  相似文献   

5.
Whole-cell patch-clamp recordings were obtained from 116 freshly dissociated neuronal somata from the optic lobe of adult locusts (Schistocerca gregaria). Prerequisites were a papain treatment and the directed transfer of somata to the recording chamber by dabbing. Of the recorded somata, 65 were from lamina and 51 from other optic lobe neurons. All somata supported voltage-activated outward currents and some (24% of optic lobe, 3% of lamina neurons) also fast inward currents. Most lamina neurons supported an outward current that activated (V 1/2=−8.5 mV) and inactivated rapidly and a sustained outward current. Some lamina and most optic lobe neurons expressed only a sustained outward current (V 1/2=−9.4 mV). GABA and histamine elicited inward currents at negative holding potentials. Most optic lobe (95%) but only 18% of lamina neurons showed a γ-aminobutyric acid (GABA) current, whereas a similar percentage of optic lobe (50%) and lamina neurons (67%) expressed a histamine current. Both currents reversed near the chloride equilibrium potential, were reversibly reduced by picrotoxin, and did not show rundown. Thus, they likely represent chloride currents mediated by ionotropic receptors. Our data indicate that the lamina neurons recorded mainly represent monopolar cells postsynaptic to histaminergic photoreceptors. The optic lobe neurons, on which GABA and histamine apparently act as inhibitory neurotransmitters, are more heterogeneous. Accepted: 30 November 1997  相似文献   

6.
Paraulopus brevirostris, P. filamentosus, P. japonicus, P. legandi, P. maculatus, and P. oblongus are redescribed. All species are included in the Paraulopus oblongus group, characterized by having no supraocular ridge, 2.5–3.5 scales above the lateral line, and small adult body size (70–150 mm SL). In addition, P. atripes, from the Indian Ocean, is described as a new species of the P. oblongus group, being defined by the following combination of characters: small antrorse dentary process on chin; eye directed laterally; pelvic fin black in males; caudal fin white; 32–34 gill rakers; 45–46 pored lateral-line scales; and 3.5 scales below lateral line. Paraulopus albimaculatus is regarded as a junior synonym of P. brevirostris, based on examination of type specimens. A key to species in the P. oblongus group is included. Received: September 2, 2002 / Revised: January 31, 2003 / Accepted: February 17, 2003  相似文献   

7.
In this article we describe the identification of endophytic bacteria belonging to three groups isolated from shoot tip cultures of banana cv. Grand Naine in a recent study (Thomas et al. 2008) based on partial 16S rRNA gene sequence homology analysis. The first group included banana stocks that displayed obvious colony growth on MS based tissue culture medium during the first in vitro passage. The second group constituted stocks that were tissue index-negative for cultivable bacteria initially but turned index-positive after a few to several (4–8) in vitro passages while the third group formed one sub-stock that turned index-positive after about 18 passages. The organisms belonged to about 20 different genera comprising of α, β, γ-proteobacteria, Gram-positive firmicutes and actinobacteria. Visibly expressing easily cultured organisms during the first in vitro passage included Enterobacter, Klebsiella, Ochrobactrum, Pantoea, Staphylococcus and Bacillus spp. Organisms of second group that were not detected or non-culturable originally constituted Brevundimonas, Methylobacterium, Alcaligenes, Ralstonia, Pseudomonas, Corynebacterium, Microbacterium, Staphylococcus, Oceanobacillus and Bacillus spp. while the third group that turned cultivable after extended in vitro culturing included mostly non-filamentous actinobacteria (Brachybacterium, Brevibacterium, Kocuria and Tetrasphaera spp.). The identification results suggested that the endophytes of second and third groups were not strictly obligate or fastidious microbes but those surviving in viable but-non-culturable (VBNC) state and displaying gradual activation to cultivable form during continuous tissue culturing. Several of the organisms isolated are known as beneficial ones in agriculture while some organisms have possible implications in human health. The use of tissue cultures for isolating uncommon endophytes is discussed. Supply of live bacterial cultures or genetic material for research purpose is subject to their revival from glycerol stocks (as some of the organisms showed poor tolerance) and the requestor obtaining written permission from the Director General, Indian Council of Agricultural Research, New Delhi-110001.  相似文献   

8.
Recent phylogenetic research suggests that Malvaceae s.l. comprises formerly Tiliaceae, Byttneriaceae, Bombacaceae, and Sterculiaceae. Corchoropsis is traditionally included in Tiliaceae or Sterculiaceae and is distributed in China, Korea, and Japan. One to three species have been recognized for this genus. Phylogenetic relationships among the Malvacean taxa have been intensively studied with molecular data, and the evolution of their morphological characteristics has been re-interpreted accordingly. However, no Corchoropsis species have been included for their phylogenetic position. Here, three chloroplast coding regions—rbcL, atpB, and ndhF, from Corchoropsis psilocarpa and Corchoropsis crenata—were amplified and sequenced, then compared with other Malvacean taxa. This analysis of the three plastid gene sequences now places Corchoropsis species in Dombeyoideae, as previously proposed by Takeda (Bull Misc Inform Kew 365, 1912), Tang (Cathaya 4:131–150, 1992), and Bayer and Kubitzki (2003). Within Dombeyoideae, Corchoropsis forms a strongly supported sister relationship with the DombeyaRuizia clade.  相似文献   

9.
This paper deals with taxonomy and phylogenetics of the genus Eurycletodes Sars, 1909 (Copepoda: Harpacticoida: Argestidae). Samples, collected from the southeast Atlantic on board RV “Meteor” during the cruises DIVA-1 (M48/1) and DIVA-2 (M63/2), contain specimens of Eurycletodes. Eurycletodes is characterized as a monophylum by A1 segments III + IV fused, basal seta of md palp lost, exp of md palp reduced to 1 seta or completely lost. Similarly, the subgenera Eurycletodes (Eurycletodes) and Eurycletodes (Oligocletodes) are characterized as monophyletic by the loss of the inner seta on P1 exp2 (apomorphic to E. (E.)) and the absence of the inner seta on P5 endopodal lobe (apomorphic to E. (O.)). Eurycletodes profundus is renamed as E. (O.) profundus. Eurycletodes ephippiger is the only species of the genus without subgeneric designation. Eurycletodes (O.) diva sp. nov. is described. The new species differs from described species of the genus by a larger body size, P5 endopodal lobe only slightly protruding, last segment of A1 with 2 outer setae, furcal rami elongated between setae VII and IV. The occurrence of 2 specimens of Eurycletodes (O.) diva sp. nov. at 2 sites separated by the Walvis Ridge supports the hypothesis that geographic obstacles do not prevent harpacticoid copepods from spreading in the deep sea.  相似文献   

10.
Peter Kučera 《Biologia》2010,65(5):832-836
The paper includes assignation of nomenclatural types to Slovak syntaxa dominated naturally by Picea abies, i.e. to 1 order (Athyrio filicis-feminae-Piceetalia Hadač ex Hadač et al. 1969) and 14 associations and 5 subassociations of the alliances Piceion excelsae Pawłowski ex Pawłowski et al. 1928, Athyrio alpestris-Piceion Sykora 1971, Oxalido-Piceion Hadač et al. 1969 and Chrysanthemo rotundifolii-Piceion (Krajina 1933) Hadač et al. 1969. The association name Avenello-Piceetum excelsae Hadač et al. 1969 is validated. Essential syntaxonomical notes to syntaxa Athyrio alpestris-Piceion, Calamagrostio villosae-Piceetum are included as well as nomenclatural comments to Vaccinio-Piceetea and Athyrio-Piceetalia.  相似文献   

11.
12.
Symptoms of fairy rings caused by Lepista sordida have been reported on Zoysiagrass (Zoysia spp.) turf maintained at fairway height (2 cm), but not on bentgrass (Agrostis spp.) maintained at putting green height (0.5 cm). The mycelia of this fungus inhabit primarily the upper 0–2 cm layer of the soil extending into the thatch. To compare conditions for the mycelial growth in Z. matrella turf to those in A. palustris turf, we examined the effects of nutrients, temperature, water potential, and pH in the field as well as in the laboratory. Greater growth of the mycelia was observed in medium that included hot water extracts from soil of the 0–1 cm zone in Z. matrella turf compared to that from A. palustris. The upper soil layer in Z. matrella turf contained more organic matter from clippings than that in A. palustris. The temperature and water potential of the 0–2 cm soil zone in Z. matrella turf were also more favorable for the mycelial growth. The soil pH values of this zone in Z. matrella turf were less favorable compared to A. palustris but within the range for accelerating mycelial growth. Part of this study was presented orally at the 46th meeting of the Mycological Society of Japan in 2002  相似文献   

13.
Synopsis Two new species of the genus Oreoglanis, O. jingdongensis and O. immaculatus are described from the Mekong and Salween River basins, respectively, of Yunnan Province, China. Oreoglanis jingdongensis can be distinguished from other Oreoglanis species by the following characters: lower lip with a distinct median notch, posterior edge smooth or with indentations; caudal fin lunate and lower lobe longer than upper lobe. Oreoglanis immaculatus can be distinguished from its congeners by the following features: lower lip with a strait median notch, posterior edge with indentations; caudal fin emarginate and lower lobe about the same length as upper lobe, having no yellow patches on sides of body below adipose fin.  相似文献   

14.
The Pleurotus eryngii species-complex includes taxa of the northern hemisphere growing in association with plants of the family Apiaceae (umbellifers). In this study, 45 Pleurotus strains were isolated from five different host-plants: Ferula ovina, F. assa-foetida, Smyrniopsis aucheri, Kellusia odoratissima, and Cachrys ferulacea; all plant species, with the exception of C. ferulacea, are reported for the first time as hosts for this fungal group. Random amplified polymorphic DNA-PCR (RAPD) analysis and nucleotide sequence data from the internal transcribed spacer of the nuclear rRNA genes (ITS1, 5.8S and ITS2) were used for assessing genetic diversity and for determining phylogenetic relationships among the populations studied. Results permitted the grouping of the strains studied into three major clusters corresponding mainly to the nature of the host-plant: the first included isolates collected from Ferula spp. only, the second included isolates originating from C. ferulacea only but from various sampling locations, and the third included all K. odoratissima and S. aucheri associated strains plus a few isolates collected from F. ovina and C. ferulacea. The grouping of the Iranian material, in conjunction with the position in the resulting phylograms of other previously obtained P. eryngii complex sequences, revealed that the first cluster is related to the asiatic ‘P. nebrodensis’ (or to the asiatic Ferula spp. associated Pleuroti), the second forms a rather distinct lineage which is linked with reference strains originally classified as P. fossulatus, whereas the third cluster falls within the main part (or the “core”) of this complex, i.e., P. eryngii. Pleurotus populations growing on umbellifers in Iran seem either to have recently diverged through a sympatric speciation process based mainly on ecological factors (e.g., P. fossulatus), or they form part of a rather wide agglomerate associated with various host-plants where exchange of genetic material is still in progress (i.e., P. eryngii).  相似文献   

15.
The Amy locus polymorphism of Drosophila subobscura is used as a model system for an experimental population genetic study of adaptive significance of α-amylase activity on substrates of different carbohydrate compositions. So far, fitness components have not commonly been included in ecological-genetic studies of α-amylase polymorphism in this species. In the present paper, fitness components are analyzed in relation to different amylase activities in D. subobscura individuals homozygous for the “slow” and the “fast” Amy allele, associated with substrates of different carbohydrate compositions. The results indicate a significant effect of substrate carbohydrate composition on fitness components of the genotypes homozygous for S or F Amy allele in D. subobscura through their enzyme activity. The text was submitted by the authors in English.  相似文献   

16.
The aim of this study is to investigate the role of anti-α-actinin antibodies in patients with new-onset systemic lupus erythematosus (SLE). Thirty-six patients with SLE, 16 of whom had lupus nephritis (LN), and 53 healthy controls were included. The clinical and laboratory parameters of patients were collected from medical records or by questionnaire. Serum anti-α-actinin Abs was measured by competitive enzyme linked immunosorbent assay (ELISA). Our results show that the OD value of serum anti-α-actinin Abs in SLE patients was significantly lower than that in normal controls (1.212 ± 0.244 vs. 1.364 ± 0.202, P = 0.002); seven of 36 SLE patients were seropositive for anti-α-actinin Abs, which was significantly higher than in normal controls (19.4 vs. 3.8%, P = 0.028). There were no significant differences of clinical parameters between the anti-α-actinin Abs-positive patients and the negative patients. The positive rate of the term urine casts, elevated IgM and IgA in anti-α-actinin Abs-positive patients were higher than that in the negative patients. The OD values of serum anti-α-actinin Abs negatively correlated with disease activity (R s = −0.352, P = 0.035). Anti-α-actinin Abs may be a useful marker of the disease activity of SLE; in addition, it may be used as a complementary parameter to differentiate LN from SLE without nephritis.  相似文献   

17.
The honeybee, Apis mellifera, is a valuable model system for the study of olfactory coding and its learning and memory capabilities. In order to understand the synaptic organisation of olfactory information processing, the transmitter receptors of the antennal lobe need to be characterized. Using whole-cell patch-clamp recordings, we analysed the ligand-gated ionic currents of antennal lobe neurons in primary cell culture. Pressure applications of acetylcholine (ACh), γ-amino butyric acid (GABA) or glutamate induced rapidly activating ionic currents. The ACh-induced current flows through a cation-selective ionotropic receptor with a nicotinic profile. The ACh-induced current is partially blocked by α-bungarotoxin. Epibatidine and imidacloprid are partial agonists. Our data indicate the existence of an ionotropic GABA receptor which is permeable to chloride ions and sensitive to picrotoxin (PTX) and the insecticide fipronil. We also identified the existence of a chloride current activated by pressure applications of glutamate. The glutamate-induced current is sensitive to PTX. Thus, within the honeybee antennal lobe, an excitatory cholinergic transmitter system and two inhibitory networks that use GABA or glutamate as their neurotransmitter were identified.  相似文献   

18.
The goal of this study is to define the effects of TCF4 hemizygosity in the context of a larger segmental deletion of chromosome 18q. Our cohort included 37 individuals with deletions of 18q. Twenty-seven had deletions including TCF4 (TCF4 +/); nine had deletions that did not include TCF4 (TCF4 +/+); and one individual had a microdeletion that included only the TCF4 gene. We compared phenotypic data from the participants’ medical records, survey responses, and in-person evaluations. Features unique to the TCF4 +/ individuals included abnormal corpus callosum, short neck, small penis, accessory and wide-spaced nipples, broad or clubbed fingers, and sacral dimple. The developmental data revealed that TCF4 +/+ individuals were only moderately developmentally delayed while TCF4 +/ individuals failed to reach developmental milestones beyond those typically acquired by 12 months of age. TCF4 hemizygosity also conferred an increased risk of early death principally due to aspiration-related complications. Hemizygosity for TCF4 confers a significant impact primarily with regard to cognitive and motor development, resulting in a very different prognosis for individuals hemizygous for TCF4 when compared to individuals hemizygous for other regions of distal 18q.  相似文献   

19.
Attempts by biogeographers to understand biotic diversification in the Amazon have often employed contemporary species distribution patterns to support particular theories, such as Pleistocene rainforest refugia, rather than to test among alternative hypotheses. Suture zones, narrow regions where multiple contact zones and hybrid zones between taxa cluster, have been seen as evidence for past expansion of whole biotas that have undergone allopatric divergence in vicariant refuges. We used coalescent analysis of mutilocus sequence data to examine population split times in 22 pairs of geminate taxa in ithomiine and heliconiine butterflies. We test a hypothesis of simultaneous divergence across a suture zone in NE Peru. Our results reveal a scattered time course of diversification in this suture zone, rather than a tight cluster of split times. Additionally, we find rapid diversification within some lineages such as Melinaea contrasting with older divergence within lineages such as the Oleriina (Hyposcada and Oleria). These results strongly reject simple vicariance as a cause of the suture zone. At the same time, observed lineage effects are incompatible with a series of geographically coincident vicariant events which should affect all lineages similarly. Our results suggest that Pleistocene climatic forcing cannot readily explain this Peruvian suture zone. Lineage‐specific biological traits, such as characteristic distances of gene flow or varying rates of parapatric divergence, may be of greater importance.  相似文献   

20.
Pyrimidine salvage pathways are vital for all bacteria in that they share in the synthesis of RNA with the biosynthetic pathway in pyrimidine prototrophs, while supplying all pyrimidine requirements in pyrimidine auxotrophs. Salvage enzymes that constitute the pyrimidine salvage pathways were studied in 13 members of Pseudomonas and former pseudomonads. Because it has been established that all Pseudomonas lack the enzyme uridine/cytidine kinase (Udk) and all contain uracil phosphoribosyl transferase (Upp), these two enzymes were not included in this experimental work. The enzymes assayed were: cytosine deaminase [Cod: cytosine + H2O → uracil + NH3], cytidine deaminase [Cdd: cytidine + H2O → uridine + NH3], uridine phosphorylase [Udp: uridine + Pi ↔ uracil + ribose – 1 - P], nucleoside hydrolase [Nuh: purine/pyrimidine nucleoside + H2O → purine/pyrimidine base + ribose], uridine hydrolase [Udh: uridine/cytidine + H2O → uracil/cytosine + ribose]. The assay work generated five different Pyrimidine Salvage Groups (PSG) designated PSG1 – PSG5 based on the presence or absence of the five enzymes. These enzymes were assayed using reverse phase high-performance liquid chromatography techniques routinely carried out in our laboratory. Escherichia coli was included as a standard, which contains all seven of the above enzymes.  相似文献   

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