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1.
Six sandy beach stations along the Jordan Gulf of Aqaba were selected for macrofaunal examination during November 1980. Fifteen core samples (0.01 m2 to a depth of 10–15 cm) were taken at each station; five at the high tide line, five at the low tide line, and five midway. Twenty-two taxa were encountered from all stations. Polychaetes were the most diverse group with seven taxa, followed by molluscs and crustaceans with six and five taxa respectively. Animal diversity, using the Shannon-Wiener Index, was generally low. Based on the biological index value of McCLOSKEY (1970), seven taxa were considered the community dominants. These are: the polychaetes, Glycera tesselata, Pisione remota, Saccocirrus sp., and Perinereis nuntia; the isopod Eurydice arabica; a nemertean and an oligochaete.  相似文献   

2.
  • 1 A previous study suggested the use of certain insects groups as indicators for detecting organic olive farming in Southern Spain. To validate the use of these groups, insects were collected from olive orchards in Cordoba and Granada, comprising two Andalusian provinces with different surrounding landscapes.
  • 2 Canopies were sampled using the branch‐beating technique during pre‐blooming and post‐blooming periods over 3 years in Granada (1999, 2000 and 2003) and 1 year in Cordoba (2003).
  • 3 Using a nonparametric linear discriminant analysis method, based on the k‐nearest neighbour algorithm, two discriminant functions were constructed. A first discriminant model took into account interannual variability in Granada Province and the second model focused on environmental heterogeneity between the two provinces. Cross‐validation techniques, such as leave‐one‐out and split‐sample, were applied to the associated discriminant functions for each model to check their performance.
  • 4 Even though differences existed with respect to the insect composition of the regions, the second model correctly classified 78.1% of the sampled blocks under the non‐organic and organic farming systems at the same time as taking into account two orders: Coleoptera and Hemiptera [excluding Euphyllura olivina olivina (Psyllidae) and the Heteroptera suborder]. The results suggest that the relative abundance of these groups in the post‐blooming period could constitute a potential bio‐indicator of organic olive farming system.
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3.
The gadoid fishes Theragra finnmarchica from the coast of northern Norway and Theragra chalcogramma from the north‐east Pacific could not be taxonomically discriminated by sequencing the mitochondrial cytochrome c oxidase I (COI) gene. However, the taxa differed in 10 of 42 non‐osteological and in four of 17 osteological characters. Ontogenetic changes were found for 16 of the examined non‐osteological characters. Five taxon‐specific characters, unaffected by ontogenetic scaling, were examined by discriminant analysis. A 100% correct classification was obtained from a discriminant function based on number of pyloric caeca and number of gill rakers on the upper part of the gill arch. However, all examined characters overlapped between the two taxa, except the number of pyloric caeca. On the basis of their genetic similarity and slight morphological differences, T. finnmarchica should be considered a junior synonym of T. chalcogramma.  相似文献   

4.
Determination of the optical isomers of insecticidal pyrethroids was carried out by gas-liquid chromatography. Chrysanthemic acid, which was obtained during hydrolysis of the corresponding pyrethroids, was esterifled with d- or l-2-octanol and the diastereoisomer ester derivatives were resolved on a column of Chromosorb W coated with 10% QF–1. All four isomers, d-trans, l-trans, d-cis and l-cis chrysanthemic acids, could be separated. These compounds were not isomerized during hydrolysis, esteriflcation or gasliquid chromatographic operations and their proportions were accurately determined from their peak area ratios.  相似文献   

5.
16 morphological characters were assessed in 300 plants sampled from 27 populations ofPolygonum aviculare sensu lato representative of the whole ecological range of the species in Belgium. The three multivariate treatments performed, namely principal component analysis, cluster analysis and discriminant analysis provide evidence thatP. aviculare can be divided in 4 units, roughly corresponding to the four taxa recognized byChrtek. However, the results point out that subsp.monspeliense and subsp.calcatum should be included at the varietal rank within respectively subsp.aviculare (=P. heterophyllum) and subsp.aequale (=P. arenastrum) as defined byLindman. Fruit dimensions, fruit shape and tepal length are the most discriminant characters for separating the four taxa, while several other characters are discriminant at the population level only. The evolutionary significance of the variation pattern of the whole complex is discussed in terms of life history differentiation and ecological specialization.  相似文献   

6.
The taxonomy of the Narcissus Flycatcher Ficedula narcissina–Yellow‐rumped Flycatcher Ficedula zanthopygia complex from East Asia has long been debated. Most authors recognize two species: F. narcissina, with the subspecies narcissina (most of Japan and Sakhalin Island), owstoni (south Japanese islands) and elisae (northeast China) and F. zanthopygia (monotypic), although species status has been proposed for elisae and sometimes for owstoni. Here, we revise the taxonomy of this complex based on an integrative approach utilizing morphology, songs and mitochondrial and nuclear DNA for all taxa. All taxa were diagnosably different in plumage, and there were also structural differences among them, although the northernmost populations of owstoni (sometimes recognized as jakuschima and shonis) were somewhat intermediate in plumage, structure and male plumage maturation between southern populations of owstoni and narcissina. All taxa had different songs, and a discriminant function analysis of four song variables correctly classified 100% of all songs. A strongly supported phylogeny was recovered based on three mitochondrial genes and three nuclear introns (total of 3543 bp), revealing a sister relationship between F. zanthopygia and the other taxa, between F. n. narcissina and F. n. owstoni, and between F. n. elisae and F. n. narcissina + F. n. owstoni. The corrected COI distances among the three F. narcissina subspecies ranged from 2.8% (narcissinaowstoni) to 8.2% (narcissinaelisae). We suggest that the congruent differences in multiple independent traits and the deep genetic divergences among the four taxa in the F. narcissina–F. zanthopygia complex support treatment of all of these taxa as separate species. However, we acknowledge the paucity of data for F. owstoni and recommend further studies of this taxon. We suggest listing both F. elisae and F. owstoni, which have small and fragmented populations, as globally threatened.  相似文献   

7.
1. Benthic macroinvertebrates (MI) are commonly used to assess freshwater ecosystems with the reference condition approach. Such assessments necessitate control for natural community variation, either by categorical typologies or by predictive models that have been widely and successfully developed for running water biota but not previously for lake profundal invertebrates. 2. We evaluated four modelling techniques [multivariate regression tree (MRT), limiting environmental differences, nonparametric multiplicative regression (NPMR) and River Invertebrate Prediction And Classification System (RIVPACS) and the operative Finnish lake typology for assessing taxonomic completeness (observed‐to‐expected number of taxa, O/E) of profundal MI assemblages. We used data from 74 and 33 minimally disturbed reference lake basins for calibration and validation of the approaches, respectively, and 72 test basins subject to various anthropogenic pressures to evaluate sensitivity to detect impact. Either all predicted taxa (threshold probability of capture Pt = 0+) or only those predicted to be captured with ≥0.25 probability were used to calculate O/E. 3. With Pt = 0.25, all four modelling approaches were accurate (mean O/E = 0.966–1.053) but imprecise (SD of O/E = 0.279–0.304) in predicting the fauna actually observed in validation sites. All models were subtly more precise than a null model (mean 1.038, SD 0.343) or the typology (1.046, 0.327). The taxon‐specific NPMR model was slightly more precise than the other three models based on site groupings. 4. The O/E values correlated relatively weakly (r = 0.55–0.86) among the approaches, which thus produced contrasting lake‐specific assessments, despite their seemingly comparable performances. Indeed, typology, suggesting that MI assemblages were impaired in 56% of test sites, was more sensitive than the other approaches (26–46%) as an indicator of human‐induced deterioration. However, this greater ostensible sensitivity seemed to be biased, as lake morphometry, a main driver of natural community variation, remained uncontrolled by the typology. 5. Generally, our exercise illustrates the inconclusiveness of the common validation criteria for the assessment methods. The apparent poor predictability of the profundal fauna, irrespective of the method, may partly stem from large observation error, which could be alleviated by more intensive sampling. However, instead of an O/E‐taxa index, some other metric encompassing quantitative aspects might be preferable for assessing these species‐poor communities.  相似文献   

8.
Twenty‐four polymorphic microsatellite loci were isolated and characterized from an AAG‐enriched genomic library of Sinojackia xylocarpa. The average allele number of these microsatellites was 3.3 per locus, ranging from two to seven. The observed and expected heterozygosities at population level were 0.10–0.83 and 0.10–1.00, respectively. In addition, successful cross‐species amplification of this set of microsatellites in three other species of Sinojackia and a closely related taxon, Changiostyrax dolichocarpa, suggested that this set of microsatellite markers should provide a useful tool for genetic and conservation studies of Sinojackia species and other closely related taxa in the Styracaceae.  相似文献   

9.
In this study, the yellow-green alga Vaucheria was collected from 86 sites with different environmental characteristics. A principal component analysis of the sites revealed a model with four principal components explaining 64.7% of the total variance in the data set. The principal components were interpreted as nutrient enrichment, ions, current, and buffer capacity. In total, seven Vaucheria species were found: V. taylorii, V. debaryana, V. sessilis, V. geminata, V. terrestris, V. walzii, and V. woroniniana. V. taylorii was noted only three times, V. terrestris occured exclusively at terrestrial sites, the remaining taxa were frequent. Vaucheria seems to have its optimal growth at lower temperatures; in the cold season thick covers were observed, which exceeded the abundance in summer. A discriminant analysis revealed that growth types are highly explained by current; high flow velocity favors the development of pads. Species occurrence along artificial gradients consisting of the obtained principal components were analyzed simultaneously by means of a canonical correspondence analysis. V. sessilis occurred widely with no preferences, but three species showed a distinct pattern within the gradient analysis: V. woroniniana mainly occurred at elevated pH and total alkalinity, V. walzii was favored by increased ion contents and slow current, and V. geminata clearly preferred unpolluted sites with decreased pH and alkalinity values. This species may be used as an indicator species for unpolluted locations, however some taxonomic uncertainties remain to be first resolved.  相似文献   

10.
1. Surface sediment samples of subfossil chironomid head capsules from 47 lakes in southern West Greenland were analysed using multivariate numerical methods in order to explore the relationship between chironomid assemblages and selected environmental variables. The study lakes are located along a climate gradient ranging from coastal maritime conditions near the Davis Strait to a continental climate near the margin of the Greenland ice sheet. 2. High‐resolution surface water temperatures were measured through the summer season using automatic data loggers in 21 of the study lakes. The mean July surface water temperature (1999) ranged from 7.3 to 16.5 °C in the data set. 3. In all lakes, a total of 24 chironomid taxa were recorded; Micropsectra, Psectrocladius, Chironomus and Procladius were the dominant genera. There was a strong correlation between the trophic variables [total nitrogen and total phosphorus (TN, TP)] and temperature, and in redundancy analysis (RDA) the three variables explained almost equal significant amounts of variation in the chironomid data (19.8–22.3%). However, temperature lost significant explanatory power when the effect of TN was partialled out in RDA. 4. The lakes were classified using two‐way indicator species analysis (TWINSPAN ) into eight groups defined by temperature, trophic variables, salinity (conductivity) and lake‐morphometric data. Fourteen chironomid taxa showed significant differences in percentage abundances among groups, with Heterotrissocladius, Micropsectra, Ablabesmyia and Chironomus as the most robust group‐indicator taxa. Forward selection of taxa in multiple discriminant analysis was used to fit chironomid assemblages into lake groups. Using only eight taxa, 95% of lakes were correctly classified at a second TWINSPAN division level (four groups) and 85% of lakes at a third division level (eight groups). 5. This study showed that there is considerable potential in using subfossil chironomid head capsules as paleoenvironmental indicators in both short‐ and long‐term (down‐core) studies of lake ontogeny and palaeoclimate conditions in West Greenland. However, because of the strong correlation between temperature and trophic variables, a quantitative reconstruction of lake‐ and habitat‐type is recommended, in combination with direct reconstruction of single variables such as temperature.  相似文献   

11.
The chromosomes of 22 animals of four subspecies of the genus Ateles (A. paniscus paniscus, A. p. chamek, A. belzebuth hybridus, and A. b. marginatus) were compared using G/C banding and NOR (nucleolar organizer region) staining methods. The cytogenetic data of Ateles in the literature were also used to clarify the phylogenetic relationships of the species and subspecies and to infer the routes of radiation and speciation of these taxa. Chromosomes 6 and 7 that showed more informative geographic variation and the apomorphic form 4/12, exclusively in A. p. paniscus, are the keys for understanding the evolution, radiation, and specification of the Ateles taxa. The ancestral populations of the genus originated in the southwestern Amazon Basin (the occurrence area of A. paniscus chamek) and spread in the Amazon Basin and westward, crossing the Andes and colonizing Central America and northwesternmost regions of South America. The evolutionary history of the northern South American taxa is interpreted using the model of biogeographical evolution postulated by Haffer [Science 185:131–137, 1969]. Ateles paniscus paniscus is the genetically most differentiated form and probably derives from A. belzebuth hybridus. Based on the karyotype differences, the populations of Ateles can be divided into four different group. These findings indicate the necessity of a more coherent taxonomic arrangement for the taxa of Ateles. Am. J. Primatol. 42:167–178, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

12.
Relationships between taxonomic composition of shallow epilithic algal communities and nine environmental variables in 32 lakes of different trophic states in Ireland were explored using gradient analysis. A canonical correspondence analysis using four representative environmental variables, alkalinity (correlated with pH and conductivity), maximum phytoplankton chl a (CHLmax) (correlated with total P, total N, and chl), turbidity, and water color explained 21% of the variance in taxa distributions. The first two axes were significant and accounted for 77% of the variance in the periphyton–environmental relationship. The first axis was strongly related to alkalinity and color, which reflected geology and land use in the watersheds. The second axis was most correlated with CHLmax, and separation of lakes corresponded to their Organization for Economic Cooperation and Development (OECD) trophic classification based on water chemistry. Eutrophic lakes were characterized by cyanobacteria taxa and Stigeoclonium sp. Diatoms and desmids were generally more abundant in oligotrophic and mesotrophic lakes. Values for diatom trophic indices were poor indicators of trophic state. Weighted averaging regression and calibration techniques were used to develop transfer functions between 84 taxa and total P, total N, and CHLmax. The total P inference model predicted OECD trophic classification correctly for 84% of the lakes. Values for taxa preferences resulting from such models can provide the foundation for biomonitoring schemes using extant periphyton communities. The turnover time of periphyton taxa should integrate changes in environmental conditions at a temporal scale intermediate to surface‐sediment fossil diatom assemblages and water column variables, which may be more appropriate for detecting annual changes.  相似文献   

13.
Teucrium stachyophyllum P. H. Davis was first described as a separate species in the ‘Syrian, Lebanon and Palestine Flora’, but was reduced to a subspecies of T. lamiifolium d’Urv. in the ‘Turkish Flora’. Studies on the macro‐ and micro‐morphology as well as the anatomy of populations of T. lamiifolium subsp. stachyophyllum (P. H. Davis) Hedge & Ekim and T. lamiifolium subsp. lamiifolium in Turkey have been carried out based on herbarium specimens and field observations. The results from the anatomical studies on stems and leaves show that although the two taxa are similar in stem anatomy, they differ in terms of mesophyll thickness and occurrence of crystals in the upper epidermal cells of the leaf. Light and scanning electron microscope analyzes revealed striking differences in colour, size, sculpture and gland density between nutlets of the two taxa. Morphological studies also showed that there were important differences between the two taxa in terms of inflorescence, indumentum, and stem length and thickness. In addition, the essential oils from aerial parts of T. lamiifolium subsp. stachyophyllum and T. lamiifolium subsp. lamiifolium were isolated by steam distillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). The major components were characterized as β‐caryophyllene (23.5–44.8%), trans‐β‐bergamotene (22.4–26.4%), germacrene D (22.2%) and (Z)‐β‐farnesene (14.0%) for subp. lamiifolium and trans‐β‐bergamotene (38.1–41.1%) and β‐caryophyllene (8.7–8.9%) for subsp. stachyophyllum, respectively. As a result of the studies, it is proposed that the taxon treated as T. lamiifolium subsp. stachyophyllum in the Turkish flora should be raised to specific rank as T. stachyophyllum.  相似文献   

14.
We hybridized whole human chromosome specific probes to metaphases of the black-and-red howler monkey Alouatta belzebul in order to establish chromosomal homology between humans and black-and-red howlers. The results show that the black-and-red howler monkey has a highly rearranged genome and that the human chromosome homologs are often fragmented and translocated. The number of hybridization signals we obtained per haploid set was 40. Nine human chromosome probes gave multiple signals on different howler chromosomes, showing that their synteny is disturbed in A. Belzebul. Fourteen black-and-red howler autosomes were completely hybridized by one human autosomal paint, six had two signals, three had three signals, and one chromosome had four signals. Howler chromosomes with multiple signals have produced 12 chromosomal syntenies or hybridization associations which differ from those found in humans: 1/2, 2/20, 3/21, 4/15, 4/16, 5/7, 5/11, 8/18, 9/12, 10/16, 14/15, and 15/22. The hybridization pattern was then compared with those found in two red howler taxa and other mammals. The comparison shows that even within the genus Alouatta numerous interchromosomal rearrangements differentiate each taxa: A. belzebul has six unique apomorphic associations, A. seniculus sara and A. seniculus arctoidea share seven derived associations, and additionally A. seniculus sara has four apomorphic associations and A. seniculus arctoideaseven apomorphic associations. A. belzebul appears to have a more conserved karyotype than the red howlers. Both red and black-and-red howlers are characterized by Y-autosome translocations; the peculiar chromosomal sex system found in the red howler taxa could be considered a further transformation of the A. belzebul sex system. The finding that apparently morphologically similar or even identical taxa have such extreme genomic differences has important implications for speciation theory and neotropical primate conservation. Am. J. Primatol. 46:119–133, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

15.
Dietary characteristics and the degree of dietary partitioning by five species of sympatric stingray were assessed using stomach content and sediment analyses within a coral reef lagoon at Ningaloo Reef, Western Australia (the cowtail Pastinachus atrus, blue‐spotted fantail Taeniura lymma, blue‐spotted mask Neotrygon kuhlii, porcupine Urogymnus asperrimus rays and the reticulate whipray Himantura uarnak). A total of 2804 items were recovered from the stomachs of 170 rays and 3215 individual taxa from the environment, which were used in selectivity analyses. Twenty‐four prey taxa were identified from stomach contents and pooled into 10 taxonomic categories for analysis, of which annelids, prawns, brachyurans and bivalves were the most abundant, together accounting for 96% of the diet. Himantura uarnak had the greatest interspecific dissimilarity in diet, consuming a larger proportion of crustaceans, notably penaeids (41% of total diet) than the other four species of rays, all of which had diets dominated by annelids (71–82% of total diet). Crustacean specialization by H. uarnak may exist to maximize resources and reduce competition among sympatric species. The remaining species may partition resources on the basis of space, rather than diet.  相似文献   

16.
ABSTRACT

Eight taxa of the Dipsacaceae family were examined for their fatty acid and sterol composition. Separation and identification of the lipid fraction was achieved by gas chromatography and gas chromatography-mass spectrometry. The phenotypic differences among taxa were established by cluster analysis. Correlation coefficients were obtained to investigate numerical relationships among constituents of the fatty acids. The results showed many significant correlations between different constituents, as well as four clusters of taxa using two linkage types of clustering.  相似文献   

17.
Integrative taxonomy is considered a reliable taxonomic approach of closely related and cryptic species by integrating different sources of taxonomic data (genetic, ecological, and morphological characters). In order to infer the boundaries of seven species of the evacanthine leafhopper genus Bundera Distant, 1908 (Hemiptera: Cicadellidae), an integrated analysis based on morphology, mitochondrial DNA, and hyperspectral reflectance profiling (37 spectral bands from 411–870 nm) was conducted. Despite their morphological similarities, the genetic distances of the cytochrome c oxidase subunit I (COI) gene among the tested species are relatively large (5.8–17.3%). The species‐specific divergence of five morphologically similar species (Bundera pellucida and Bundera spp. 1–4) was revealed in mitochondrial DNA data and reflectance profiling. A key to identifying males is provided, and their morphological characters are described. Average reflectance profiles from the dorsal side of specimens were classified based on linear discriminant analysis. Cross‐validation of reflectance‐based classification revealed that the seven species could be distinguished with 91.3% classification accuracy. This study verified the feasibility of using hyperspectral imaging data in insect classification, and our work provides a good example of using integrative taxonomy in studies of closely related and cryptic species. © 2015 The Linnean Society of London  相似文献   

18.
The larval shells of Antalis circumcincta (Watson, 1879) (order Dentaliida), Pertusiconcha callithrix (Dall, 1889) (order Gadilida) and of an undetermined species of uncertain systematic position are described. The material studied comprises mainly samples from deep waters, collected by expeditions along the southeast coast of Brazil. The larval shell of the three taxa matches other types previously described in the literature. Antalis circumcincta and P. callithrix have four regions (protoconch A, protoconch B, teleoconch A, teleoconch B), but differ in dimensions and sculpture from each other, while the undetermined species has three regions (protoconch A, protoconch B, teleoconch B). A morphometric approach combined with a discriminant analysis also indicates that the three taxa are significantly distinct. This study confirms patterns of larval shells at the taxonomic rank of orders but other supraspecific patterns remain uncertain.  相似文献   

19.
Metabolic fingerprinting to discriminate diseases of stored carrots   总被引:1,自引:0,他引:1  
Volatile metabolites from headspace gas of carrot cv. Vita‐treat inoculated with water or four different pathogens Botrytis cinerea, Erwinia carotovora subsp. carotovora, Aspergillus niger and Fusarium avenaceum were profiled using gas chromatography and mass spectrometry to develop a technology to discriminate diseases. The inoculation of carrot roots with water or different pathogens released a total of 137 different volatile metabolites. Among them, 39 compounds were relatively consistent and 11 were specific to one or more diseases/inoculations. E. carotovora subsp. carotovora produced seven disease‐specific metabolites: 1‐butanol, 3‐methyl; 1‐pentanol; 1‐propanol, 2‐methyl; 2,3‐butanedione; boronic acid, ethyl; butane, 1‐methoxy‐3‐methyl; and ethane, ethoxy. Some metabolites were disease/inoculation discriminatory and were not detected in all treatments: 1,2‐dimethoxy‐ethene was common in carrots inoculated with E. carotovora subsp. carotovora and B. cinerea, while 2‐butanone, 3‐chloro‐4‐hydroxy‐1,4‐diphenyl was common in carrots inoculated with E. carotovora subsp. carotovora, F. avenaceum and water‐inoculated control. The significant mass ions, based on univariate analysis, from a total of 150 (46–195 m/z) and compounds from a total of 32 were further subjected to stepwise discriminant analysis and discriminant analysis. The models for 3 days after inoculation (DAI) were better than those for 6 DAI and 3 + 6 DAI, where up to 90% of the observations were correctly classified into respective inoculations. The disease‐discriminatory compounds from different diseases/inoculations and discriminant analysis models developed here have the potential for the early detection and discrimination of postharvest diseases of carrot cv. Vita‐treat, after validation under commercial conditions.  相似文献   

20.
The taxonomy of theScutellaria pekinensis complex has been ambiguous and problematic, because morphological characters are variable. To elucidate the taxonomic structure of the Korean taxa belonging to the complex, 29 characters were measured from 99 individuals collected from 96 localities and analyzed by factor analysis, cluster analysis, and discriminant analysis. The results supported the recognition of four infraspecific taxa ofS. pekinensis Maxim, in Korea: var.ussuriensis (Regel) Handel-Mazzetti, var.alpina (Nakai) Hara, var.transitra (Makino) Hara, and var.maxima S. Kim et S. Lee. Key characters distinguishing the four varieties were inferred on the basis of multivariante analyses.  相似文献   

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