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1.
The utility of regression and correspondence models for deducing climate from leaf physiognomy was evaluated by the comparative application of different predictive models to the same three leaf assemblages. Mean annual temperature (MAT), mean annual precipitation (MAP), and growing season precipitation (GSP) were estimated from the morphological characteristics of samples of living leaves from two extant forests and an assemblage of fossil leaves. The extant forests are located near Gainesville, Florida, and in the Florida Keys; the fossils were collected from the Eocene Clarno Nut Beds, Oregon. Simple linear regression (SLR), multiple linear regression (MLR), and canonical correspondence analysis (CCA) were used to estimate temperature and precipitation. The SLR models used only the percentage of species having entire leaf margins as a predictor for MAT and leaf size as a predictor for MAP. The MLR models used from two to six leaf characters as predictors, and the CCA used 31 characters. In comparisons between actual and predicted values for the extant forests, errors in prediction of MAT were 0.6°-5.7°C, and errors in prediction of precipitation were 6-89 cm (=6-66%). At the Gainesville site, seven models underestimated MAT and only one overestimated it, whereas at the Keys site, all eight models overestimated MAT. Precipitation was overestimated by all four models at Gainesville, and by three of them at the Keys. The MAT estimates from the Clarno leaf assemblage ranged from 14.3° to 18.8°C, and the precipitation estimates from 227 to 363 cm for MAP and from 195 to 295 cm for GSP.  相似文献   

2.
Cladistic and biogeographic analyses of the genus Farrodes are presented. Two species groups are delineated within Farrodes: F. caribbianus and F. bimaculatus. Three species formerly placed in other genera– Thraulus caribbianus Traver, Thraulus roundsi Traver and Homothraulus maculatus (Needham & Murphy)–are transferred to Farrodes. The species of the F. caribbianus species group are revised. Three new species are described: F. savagei from Venezuela, F. maya and F. mexicanus from Mexico. Keys to separate the two species groups of Farrodes and the species of the F caribbianus species group are provided. Successive cladistic analyses were carried out on both adult and nymphal characters using Hennig86 and CLADOS. The matrix was composed of all available data (nymphal characters were missing for some species), from nymphal and adult stages separately and on taxa represented by both adult and nymphal characters. Species of the genera Simothraulopsis and Homothraulus (components of the Farrodes lineage) were included in the analyses, and Ecuaphkbia was used as the outgroup. Results of the four analyses are compatible. The historical biogeography of Farrodes , with a distribution from nordiern Argentina to southern Texas, is analysed using the program COMPONENT. Areas of endemism are established, and some of their relationships compared with those of other groups available in the literature.  相似文献   

3.
The South American grasshopper genus Chlorus (Melanoplinae, Dichroplini) from Bolivia, southern Brazil and Paraguay is revised. Cladistic analysis of morphological characters indicates that Chlorus constitutes a monophyletic group whose generic relationships remain unsolved. If the external morphology is considered, Chlorus showed to be related to Dichromatos , while characters from the male genitalia support the relationship between Chlorus and Eurotettix. Seven species are recognised for Chlorus with three of them described as new: Chlorus spatulus, Ch. chiquitensis and Ch. attenuatus . Keys to the species of the genus and a review of the morphological characters defining the taxa are provided.  相似文献   

4.
The genus Stericta Lederer,1863 is reviewed in China.Of the ten species treated,two species are described as new:S.corollina sp.nov.and S.digitata sp.nov.Photographs of adults and genitalia are provided.Keys to the available species are given,based on superficial characters and male genitalia.  相似文献   

5.
Morphological data were gathered from 126 herbarium specimens representing ten species of Psophocarpus. Specimens were scored for 29 vegetative, 46 inflorescence, 16 legume and six seed characters. The data were analysed using cluster analysis and ordination and the results used to produce an overall phenetic classification. The proposed classification includes a tenth species recently distinguished, but undescribed by Verdcourt. Keys are provided to the subgenera and sections, as well as the ten taxa recognized and the classification is discussed in relation to previous classifications of the genus.  相似文献   

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The morphological characters in the genus Orobanche were evaluated from the taxonomic point of view. The author finds that the plants of this genus are relatively similar to each other in respect to characters of vegetative organs, fruits and seeds. But the differences in the floral structures can be served as a basis for delimitating infrageneric taxa. The seed coat of 18 species and pollen grains of 6 species were also examined under scanning electron microscope (SEM). They seem to have little significance for distinguishing species. The result supports G. Beck’s (1930) division of the genus Orobanche into 4 sections, of which 2 occur in China, based on the characters of the inflorescence, bracteoles and calyx. The author considers that some characters, such as anther hairy or not, upper lip of corolla entire or not, lower lip longer or shorter than the upper one, the state of corolla-tube inflec tion and the hair type of filaments and plants, are important in distinguishing Chinese species. A key to the species of Orobanche in China is given. This genus consists of about 100 species, and is mostly confined to Eurasia, with over 60 species found in Caucasus and Middle Asia of USSR, where may be the mordern distribu tional centre. Orobanche L. in China is represented by 23 species, 3 varieties and l forma. As shown in Table 1, most species (12 species) are found in Xinjiang, which clearly shows a close floristic relationship between this region and Middle Asia of USSR. 6 species are endemic to China, of which 4 are confined to the Hengduan Mountains (Yangtze-Mekong-Salwin divide). The relationships between this genus and related ones of Orobanchaceae are also discussed. The author holds the following opinions: the genus Phelypaea Desf. should be considered as a member of Orobanche L. Sect. Gymnocaulis G. Beck, the monotypic genus, Necranthus A. Gilli endemic to Turkey, is allied with Orobanche L. Sect. Orobanche, the monotypic genus, Platypholis Maxim, endemic to Bonin Is. of Japan, is far from Orobanche L. in relation and should be regarded as a separate genus. The 11 OTU’s, including all the sections of Orobanche L. and 7 genera of Orobanchaceae, and 15 morphological characters were used in the numerical taxonomic treatment to test the above-mentioned suggestions. After standardization of characters, the correlation matrices were computerized. The correlation matrices were made to test the various clustering methods. At last the UPGMA clustering method was chosen and its result is shown in a phenogram. The result of numerical analysis is basically in accordance with the suggestions.  相似文献   

9.
A revision of epinepheline (Epinephelinae) and serranine (Serraninae) fishes from the Eastern Chilean South Pacific is presented, based on collections housed in Chile, Peru and the USA. Four species are recognized: Pseudogramma australis pasquensis; Diplectrum conceptione; Paralabrax humeralis and Serranus huacarii. According to literature Paralabrax semifasciatus, Serranus semifasciatus and Prionodes huascarii are relegated to the synonymy of Paralabrax humeralis and Serranus huascarii respectively. Keys for the identification of genera and species are presented, and for each species we provide a diagnosis, remarks on colors, distribution, number of species in each genus and illustration. The keys use easily observed characters for differentiating the four species of the Eastern South Pacific epinepheline and serranine fishes of Chile.  相似文献   

10.
Tropical hardwood hammocks, among the rarest and most threatened vegetative communities in the United States, occur throughout the 225-km Florida Keys archipelago as it extends toward the Caribbean from the southeast tip of peninsular Florida. Compounding their critical conservation status, tropical hardwood hammocks and the dynamics that support their peculiar species diversity in the region are poorly understood. The goal of this study was to explore the dynamics of the species compositional gradient of the hammocks along the Florida Keys, and to identify significant ecological units within the gradient. The primary data for this research were assembled from the Institute for Regional Conservation's floristic database of South Florida. We were able to extract presence/absence data for 295 species from comprehensive surveys of 23 study sites. Nonmetric multidimensional scaling was used to deconstruct the compositional trends into a reduced ordination space. Cluster analysis was subsequently used to identify discrete ecological units. Additionally, we used vector fitting to interpret the significant correlated ancillary variables. Our main results were three well-fitted nonmetric multidimensional scaling axes with three nonoverlapping ecological units. Of the ancillary variables, latitude, longitude, percent composition from biogeographical regions, richness, and area were correlated to the nonmetric multidimensional scaling results. These results increase our understanding of the community structure of the hammocks along the Florida Keys, and can contribute to increasing our ability to adequately protect and restore tropical hardwood hammocks and other similar tropical dry forest communities throughout the Caribbean.  相似文献   

11.
Cognato AI  Smith SM 《ZooKeys》2010,(56):49-64
A cladistic analysis based on 20 morphological characters was conducted for 11 species representing two valid and two synonymized Phloeotribini genera. One hundred-eighty most-parsimonious trees were recovered and the Dryotomicus Wood species were monophyletic in a mostly unresolved strict-consensus tree. The unusual antennal morphology, with the length of the first two funicular segments equal to the last three segments and a scape which is twice the length of the funicle, distinguish Dryotomicus from the other Phloeotribini genera. Hence this genus is resurrected because of monophyly and diagnostic characters. Dryotomicus oenophilissp. n. and Dryotomicus woodrexsp. n. are described from Guyana and Peru, respectively. In the male specimen of Dryotomicus oenophilis, the frons has one median and two large lateral carinae and in the male specimen of Dryotomicus woodrex, the frons has three smaller median tubercles arranged transversely. Phloeotribus puberulus Chapuis and Phloeotribus tuberculatus (Eggers) were monophyletic with the new Dryotomicus species and thus are transferred to this genus. Keys to the Phloeotribini genera and Dryotomicus species are given.  相似文献   

12.
Abstract.  The South American grasshopper genus Eurotettix (Melanoplinae, Dichroplini) from north-eastern Argentina, southern Brazil and eastern Paraguay is revised. Cladistic analysis of the morphological and karyotypic characters indicates that the monophyly of Eurotettix is supported only weakly. Thus, Eurotettix is divided into two genera, and Dichromatos gen.n. is described for Eurotettix corupa Carbonell & Mesa, E. lilloanus Liebermann (type species), E. montanus Carbonell & Mesa and E. schrottkyi Rehn. Twelve species are recognized for Eurotettix with six described as new: E. concavus sp.n. , E. latus sp.n. , E. procerus sp.n. , E. brevicerci sp.n. , E. similraphael sp.n. and E. bugresensis sp.n. Keys to the species of the genera and a review of defining morphological characters are provided.  相似文献   

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The specific composition of acarid mites occurring in dust of rural dwellings in the Far East of the USSR has been first studied and characters of their fauna have been revealed. 3 species are most frequently encountered of which Dermatophagoides pteronyssinus accounts for 56% of all finds. 6 species happened to be new for the fauna of dwellings. The typical synanthropic species Glycyphagus domesticus is totally absent from dwellings but occurs in 90% of honey-bee hives.  相似文献   

15.
This study examines scleractinian zooxanthellate coral recruitment patterns in the Florida Keys to determine if differences in density or community composition exist between regions. From July to September 2002, nine patch reefs, three in each of the upper, middle and lower Keys, were surveyed for coral recruits (colonies <5 cm in diameter) using randomly placed quadrats and transects. Coral recruits were enumerated, measured, and identified to genus. Fourteen genera of corals were observed across all sites and ranged from five to 13 per site. Densities ranged from 6.29 +/- 1.92 (mean +/- SE) to 39.08 +/- 4.53 recruits m(-2), and there were significant site and regional differences in recruit densities. The density of recruits in the upper Keys was significantly lower than in the middle and lower Keys. In addition, the upper Keys were less diverse and had a different recruit size-frequency distribution. The majority of recruits were non-massive scleractinian species that contribute relatively little to overall reef-building processes, a finding that is similar to previous studies. Fewer recruits of massive species were found in the upper Keys compared to the middle and lower Keys. The recruitment patterns of the reefs in the upper Keys could potentially hinder their ability to recover from stress and disturbances.  相似文献   

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The key for identification of species of the genus Rhipicephalus (the fauna of the USSR) on the larval phase is based on the material reared under laboratory conditions. The structure of scutum, organs of gnathosoma and coxae, chaetotaxy of idiosoma and gnathosoma were used for differential diagnosis. In addition morphometric characteristics of the above structures and their proportions were used. A special attention has been given to coexistence of species in sympatric zones, which was revealed or confirmed as a result of identification of species of the genus on larva in the ranges of the fauna of the USSR.  相似文献   

18.
Book Review     
Keys to the Insects of the European Part of the USSR. Volume III Hymenoptera. Part IV Braconidae. V. I. Tobias (ed.)  相似文献   

19.
Abstract. The rare Neotropical ant subfamily Leptanilloidinae is revised and its internal phylogeny and biogeography discussed. A new genus, Asphinctanilloides gen.n., including three new species, A. amazona, A. anae and A. manauara, and three new species of Leptanilloides , L. improvisa, L. legionaria and L. sculpturata are described. The only previously known species of the subfamily, L . biconstricta Mann (1923) , is redescribed, and the larva of L. legionaria sp.n. is described. Keys to the genera and the species, and a phylogeny of the group are provided. Emphasis has been placed on the study of abdominal and sting characters.  相似文献   

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