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1.
Along elevational gradients, phylogenetic relatedness patterns constitute a considerable source of information and may shed light on ecological processes that structure communities. This study focuses on community phylogenetic structure of planthoppers, specifically the species-rich and abundant Fulgoromorpha families (Hemiptera, Auchenorrhyncha), Cixiidae and Derbidae + Achilidae, along an elevational gradient on Mount Wilhelm (Papua New Guinea). In order to assess the factors driving planthoppers community composition, we recorded abundance data for planthoppers species at each elevation and we generated a molecular phylogeny of the local species, using Bayesian inference. We analyzed 168 individuals representing 59 local morphospecies. Using a fully resolved and well-supported phylogeny, we then investigated the phylogenetic structure of the communities by performing a Spatial Analysis of Community Diversity. We show that Cixiidae are phylogenetically clustered along the elevational gradient, whereas Derbidae + Achilidae harbor a random structure, suggesting that local adaptation to elevation shapes community structure of Cixiidae, but not that of Derbidae + Achilidae. Our findings highlight the importance of phylogenies in the study of tropical elevational gradients.  相似文献   

2.
New taxa of Achilini (Achilidae) are described from Baltic amber: Paratesum rasnitsyni gen. et sp. nov., Protomenocria notata gen. et sp. nov., Psycheona variegata gen. et sp. nov., P. striata sp. nov. Protepiptera kaweckii Usinger, 1939 (= Cixidia christinae Lefebvre, Bourgoin et Nel, 2007, syn. nov.) is redescribed with designation of a neotype. “Cixius” testudinarius Germar et Berendt, 1856, “C.” longirostris Germar et Berendt, 1856 and “Oliarus” oligocenus Cockerell, 1910 are transferred to Achilini. A key to the genera of Achilidae known from Baltic amber is provided.  相似文献   

3.
记述颖蜡蝉科Achilidae广颖蜡蝉属Catonidia 1新种:周氏广颖蜡蝉C. choui sp. nov.,给出了该属物种的名录及分类检索表。模式标本存放于贵州大学昆虫研究所。  相似文献   

4.
Alicodoxa rasnitsynigen. et sp. n. (Dictyopharinae: Orthopagini) is described based on a nymph from Rovno amber; it also occurs in Baltic amber. A small additional wax plate dorsal to the large wax plate of abdominal tergites VI-VIII is first reported in this and other genera of Dictyopharidae. A lectotype is designated for Pseudophana reticulata Germar & Berendt, 1856 transferred to Protepiptera (Achilidae): Protepiptera reticulata (Germar & Berendt, 1856), comb. n.  相似文献   

5.
G. Poinar 《BioControl》2004,49(3):239-244
Fossil evidence of parasitism byStrepsiptera is presented by the discovery of amale pupa in a halictid bee (Halictidae:Hymenoptera) and female and male pupae inrepresentatives of two families of planthoppers(Delphacidae and Achilidae: Fulgoroidea) in 15–45 million year old Dominican amber. In thecase of the delphacid, the first stagestrepsipteran larvae were making their exitfrom the brood chamber at the time of capture.The fossils are compared with extantinsect-strepsiptera associations inMesoamerica. These rare finds, which includethe first fossil record of strepsipteran larvaeassociated with a host insect, establish aminimum age for parasitism of halictid bees andplanthoppers by strepsipterans.  相似文献   

6.
The family Tropiduchidae is revised taxonomically comprising five genera and five species from Korea. Catullia vittata Matsumura is redescribed here on the basis of a series of males recently collected in Korea. Cixiopsis punctatus Matsumura and Catullia vittata Matsumura were transferred from Achilidae to Tropiduchidae and are redescribed here with male genitalia for the first time from Korea. Ommatissus binatatus Fieber previously reported was an incorrect identification of Ommatissus lofouensis Muir. Another species, Trypetimorpha koreana Kwon and Lee, is the macropterous form of Trypetimorpha japonica Ishihara. All Korean species of the Tropiduchidae are redescribed and illustrated, and an identification key to the genera of Tropiduchidae is provided.  相似文献   

7.
卡颖蜡蝉属CaristianusDistant中国种类记述(同翅目:颖蜡蝉科)周尧,袁锋,王应伦(西北农业大学昆虫研究所,陕西省杨陵区712100)关键词同翅目,颖蜡蝉科,卡颖蜡蝉属,新种,分类学,中国卡颖蜡蝉属CaristianusDistant,...  相似文献   

8.
The complete mitochondrial genomes (mitogenomes) of two DNA barcode-defined haplotypes of Metcalfa pruinosa and one of Salurnis marginella (Hemiptera: Flatidae) were sequenced and compared to those of other Fulgoroidea species. Furthermore, the mitogenome sequences were used to reconstruct phylogenetic relationships among fulgoroid families. The three mitogenomes, including that of the available species of Flatidae, commonly possessed distinctive structures in the 1702–1836 bp A+T-rich region, such as two repeat regions at each end and a large centered nonrepeat region. All members of the superfamily Fulgoroidea, including the Flatidae, consistently possessed a motiflike sequence (TAGTA) at the ND1 and trnS2 junction. The phylogenetic analyses consistently recovered the familial relationships of (((((Ricaniidae + Issidae) + Flatidae) + Fulgoridae) + Achilidae) + Derbidae) in the amino acid-based analysis, with the placement of Cixiidae and Delphacidae as the earliest-derived lineages of fulgoroid families, whereas the monophyly of Delphacidae was not congruent between tree-constructing algorithms.  相似文献   

9.
10.
The origin of the genus Homo in Africa signals the beginning of the shift from increasingly bipedal apes to primitive, large-brained, stone tool-making, meat-eaters that traveled far and wide. This early part of the human genus is represented by three species: Homo habilis, Homo rudolfensis, and Homo erectus. H. habilis is known for retaining primitive features that link it to australopiths and for being the first stone tool makers. Little is known about H. rudolfensis except that it had a relatively large brain and large teeth compared to H. habilis and that it overlapped in time and space with other early Homo. Our understanding of the paleobiology and evolution of the larger-brained H. erectus is enhanced due to its rich fossil record. H. erectus was the first obligate, fully committed biped, and with a body adapted for modern striding locomotion, it was also the first in the human lineage to disperse outside of Africa. The early members of the genus Homo are the first to tip the scale from the more apish side of our evolutionary history toward the more human one.  相似文献   

11.

Background  

The key enzymes of photosynthetic carbon assimilation in C4 plants have evolved independently several times from C3 isoforms that were present in the C3 ancestral species. The C4 isoform of phosphoenolpyruvate carboxylase (PEPC), the primary CO2-fixing enzyme of the C4 cycle, is specifically expressed at high levels in mesophyll cells of the leaves of C4 species. We are interested in understanding the molecular changes that are responsible for the evolution of this C4-characteristic PEPC expression pattern, and we are using the genus Flaveria (Asteraceae) as a model system. It is known that cis-regulatory sequences for mesophyll-specific expression of the ppcA1 gene of F. trinervia (C4) are located within a distal promoter region (DR).  相似文献   

12.
The expression of MLCK- and PEVK-domains of twitchin, as well as the unique N-terminal domain of myorod in early development of the mussel Mytilus trossulus has been studied. The MLCK-domain of twitchin and the unique N-terminal domain of myorod appear at the early stages of development, whereas the PEVK-domain of twitchin is present only in muscles of adult mussel. The sizes of genes of the N-terminal domain of myorod, obtained at the blastula stage and from the adult animal are similar, but the proteins have significant differences in the amino acid sequences. Consequently, myorod and twitchin appear at early stages of larval mussels before the formation of “adult” muscles capable of catch contraction, and at these stages both proteins are isoforms, which differ from the isoforms of adult animals. It is possible that the MLCK-domain in the “larval” isoform of twitchin is necessary for regulating the formation of the contractile apparatus of molluscan smooth muscles, while the PEVK-domain is important for the regulation of the catch state in muscles of adult animals.  相似文献   

13.
The structure and function of small intestine epithelium have been studied in overwintering frogs at various stages of hibernation. Experiments on the in vitro absorption of arginine vasotocin (AVT) have shown that the epithelium ability for absorption of this nonapeptide without hydrolysis persists during hibernation. However, there is a decline in AVT absorption observed in January–February and later on (as compared with that in October–December) which is most pronounced in March–April. Changes in the epithelial structure appear by midwinter and are growing towards spring. In April–May, enterocyte height decreased by 33%, microvilli length by 40%, and number of mitochondria by 57% relative to the values at the beginning of hibernation. The absence of signs of breakdown attests to the adaptive nature of the observed changes. The dynamics of the studied parameters reveals morphological and functional plasticity of small intestinal epithelium in Rana temporaria over the hibernation period.  相似文献   

14.
A theoretically obtained oscillatory mode of photosynthesis caused by long-wave illumination is discussed. Periodical variations in the operation of photosystem (PS) I, the electron transport chain, and the Calvin-Benson cycle take place in this mode. The changes in PS II operation are not repetitive. Damped oscillations of P700+ concentration and CO2 assimilation rate are observed in the theoretical curves. The results of modeling are quite consistent with the P700+ kinetics obtained earlier by measuring the induction of the PS I EPR signal in leaves at different temperatures.  相似文献   

15.
16.
A new complete and fully articulated specimen of the anurognathid pterosaurAnurognathus ammoni from the Upper Jurassic Solnhofen Limestone of southern Germany provides new information about the species. The skull is broader than long and quite tall. The naris and antorbital fenestra are both small and anteriorly placed, whereas the orbit is very large. The palatal elements are slender struts of bone separating large openings. The tail is short, but is neither pygostyle-like nor like that of pterodactyloids. The wingfinger, unlike that of almost all pterosaurs, is reduced to three phalanges. Pedal digit V bears two long phalanges. Reexamination of the holotype specimen revealed evidence of bony bumps on the premaxilla and dentary that may have been associated with a fringe of bristles around the mouth.Anurognathus and the other anurognathids were probably adapted to aerial insectivory in low light conditions like extant caprimulgids and insectivorous bats, and may have spent little time on the ground. The taxonomy of the Anurognathidae is reviewed and new diagnoses are presented. A cladistic analysis supports the interpretation that the Anurognathidae is the sister-group to all other pterosaurs.   相似文献   

17.
With the deployment of transgenic crops expressing δ‐endotoxins from Bacillus thuringiensis (Bt) for pest management, there is a need to generate information on the interaction of crop pests with their natural enemies that are important for regulation of pest populations. Therefore, we studied the effects of the Bt δ‐endotoxins Cry1Ab and Cry1Ac on the survival and development of the parasitoid Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) reared on Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae fed on Bt toxin‐intoxicated artificial diet. The H. armigera larvae fed on artificial diet impregnated with Cry1Ab and Cry1Ac at LC50 (effective concentration to kill 50% of the neonate H. armigera larvae) and ED50 (effective concentration to cause a 50% reduction in larval weight) levels before and after parasitization resulted in a significant reduction in cocoon formation and adult emergence of C. chlorideae. Larval period of the parasitoid was prolonged by 2 days when fed on Bt‐intoxicated larvae. No adverse effects were observed on female fecundity. The observed effects appeared to be indirect in nature, because no Bt proteins were detected through enzyme‐linked immunosorbent assay in the C. chlorideae larvae, cocoons, or adults fed on Cry1Ab‐ or Cry1Ac‐treated H. armigera larvae. The effects of Bt toxin proteins on C. chlorideae were due to early mortality of H. armigera larvae, that is, before completion of parasitoid larval development.  相似文献   

18.
The degree of linear polarization of the Hα and Hβ atomic lines in a hydrogen-containing plasma is measured. The dependence of the degree of linear polarization on the spatial anisotropy of a discharge is investigated.  相似文献   

19.
The inflorescence of Dracontium polyphyllum consists of 150 – 300 flowers arranged in recognisable spirals. The flower has 5 – 6 (90% of observed specimens), or 7 broad tepals enclosing 9 – 12 stamens (occasionally 7) inserted in two whorls. The gynoecium is trilocular (90% of observed specimens) or tetralocular. The tetralocular gynoecia are found at random among the trilocular gynoecia. Each locule encloses an ovule inserted in an axile position, in the median portion of the ovary. Each carpel has its own stylar canal. However, in the upper portion of the style, there is only one common stylar canal. Floral organs are initiated in an acropetal direction in the following sequence: tepals, stamens, and carpels. During later stages of development, the tepals progressively cover the other floral organs. The first floral primordia are initiated on the upper portion of the inflorescence. During early stages of development, the floral primordia have a circular shape. The tepals are initiated nearly simultaneously. During later stages of development, the first whorl of stamens develops in alternation with the tepals and is followed by a second whorl of stamens. The trilocular or tetralocular nature of the ovary is clearly visible during early stages of development of the gynoecium. Recent molecular studies show that Anaphyllopsis A. Hay and Dracontium L. are closely related. However, although pentamerous flowers have been observed in Anaphyllopsis, the developmental morphology of the flower of Dracontium is different from that of Anaphyllopsis.  相似文献   

20.
The permeability of ion channels for ions and substances that bind inside the pore depends on the cross-sectional area of the pore. We have constructed models of the closed, open, and desensitized α1β2γ2 GABAA receptor on the basis of known structures of both prokaryotic and eukaryotic ligand-gated channels. We employed Monte Carlo energy minimization to optimize the model structures. We have found significant pore constrictions, whose diameter depends on the functional state of the receptor in the cytoplasmic, middle, and extracellular parts of the pore-forming M2 segments. It is known that the constrictions in the middle (the 9' ring of residues) and cytoplasmic (the 2' ring of residues) parts of the M2 helices form the activation and desensitization gates of the GABAA receptor. Our computations predict that the constriction in the extracellular part of the M2 helices (the 20' ring of residues) may also serve as a gate in the GABAA receptor, whose physiological role is still unclear. Our results imply that the structures of a number of prokaryotic and eukaryotic ligand-gated channels that have been found in bacteria and lower organisms can be used for homology modeling of the pore region of the human GABAA receptor.  相似文献   

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