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1.
Phylogenetic relationships between two New World Syrphinae taxa (Diptera, Syrphidae), i.e. the highly diverse genus Ocyptamus and the large genus Toxomerus, were analysed based on molecular characters. The monophyly of both taxa was tested and the taxonomic status of included subgenera and species groups was examined. Toxomerus constitutes the monogeneric tribe Toxomerini with more than 140 described species, while Ocyptamus (tribe Syrphini) is a very diverse genus (over 300 spp.) with multiple recognised subgenera and species groups. Sequence data from three gene regions were used: the mitochondrial protein-coding gene cytochrome c oxidase subunit I (COI) and the nuclear 28S and 18S ribosomal RNA genes. The secondary structure of two expansion segments (D2, D3) of the ribosomal 28S RNA gene is presented for the family Syrphidae and used for the first time in a multiple sequence alignment. Molecular data were analysed using parsimony, maximum likelihood and Bayesian inference. Toxomerus was always recovered as monophyletic within Ocyptamus, and relationships to other New World taxa such as Salpingogaster (Eosalpingogaster) were well-supported. Only the subgenera and species groups of Ocyptamus were consistently recovered as monophyletic lineages, thus the apparent non-monophyly of Ocyptamus demands reclassification of this clade.  相似文献   

2.
3.
The tribe Acacieae (Fabaceae: Mimosoideae) contains two genera, the monotypic African Faidherbia and the pantropical Acacia, which comprise about 1200 species with over 950 confined to Australia. As currently recognized, the genus Acacia is subdivided into three subgenera: subg. Acacia, subg. Aculeiferum, and the predominantly Australian subg. Phyllodineae. Morphological studies have suggested the tribe Acacieae and genus Acacia are artificial and have a close affinity to the tribe Ingeae. Based on available data there is no consensus on whether Acacia should be subdivided. Sequence analysis of the chloroplast trnK intron, including the matK coding region and flanking noncoding regions, indicate that neither the tribe Acacieae nor the genus Acacia are monophyletic. Two subgenera are monophyletic; section Filicinae of subgenus Aculeiferum does not group with taxa of the subgenus. Section Filicinae, eight Ingeae genera, and Faidherbia form a weakly supported paraphyletic grade with respect to subg. Phyllodineae. Acacia subg. Aculeiferum (s. s.) is sister to the grade. These data suggest that characters currently used to differentiate taxa at the tribal, generic, and subgeneric levels are polymorphic and homoplasious in cladistic analyses.  相似文献   

4.
The venom apparatus morphology was examined in 25 species of Cynipoidea, representing 11 parasitoid taxa; 12 gall inducers and two inquilines. Typically the venom apparatus consists of an oval or bilobed reservoir connected to the ovipositor apparatus by a very short venom duct at the anterior end and to a single elongate unbranched venom gland at or near its posterior end. The Dufour's gland was not found in any of the examined species. The elongate unbranched venom gland and the absence of the Dufour's gland are putative cynipoid synapomorphies. The shape and size of especially the venom reservoir were found to vary considerably within the Cynipoidea. It is typically less prominent in the parasitoid taxa than in the gall inducers. Exceptions include the poppy gallers Barbotinia and Aylax, in which the venom reservoirs were remarkably small and in the rose galler Diplolepis, where only a rudimentary venom apparatus was found. Possible functional and phylogenetic implications of cynipoid venom apparatus features are discussed.  相似文献   

5.
Detailed venom reservoir and venom gland intima morphology was investigated in representatives of 178 species and 76 genera of Braconidae belonging to the subfamilies Opiinae (23 genera and 69 species) and Alysiinae (36 genera and 67 species of Alysiini, and 17 genera and 42 species of Dacnusini). The presence of an unsculptured sack–like expansion of the anterior end of the reservoir suggests a relationship between some members of the alysiine tribe Dacnusini, viz. Exotela and Chorebus , and the genera Oenonogaster and Glyphogaster , both of which are currently placed in the Alysiini. The same feature also suggests that Exotela, Chorebus, Oenonogaster and Glyphogaster may be derived from the Opiinae separately from other Alysiinae. Other dacnusines examined are indicated as forming a monophyletic taxon on the basis of their reduced and narrow reservoirs. An anterior insertion of the venom glands on to the reservoir generally supports the Phaenocarpa group of alysiine genera, with some modification, whereas the presence of a discrete, narrow posterior extension of the reservoir represents a synapomorphy for members of the Aspilota group of alysiine genera. The phylogenetic inferences from this venom apparatus study are discussed in the light of the biology of the taxa concerned. Twenty-one new combinations are made in the Opiinae and seven in the Alysiinae.  相似文献   

6.
Past classifications of the tribe Acacieae Rchb. are outlined and the confusion concerning the relationships of the three subgenera of Acacia Mill. are highlighted. A plastid DNA analysis of Acacieae shows that the genus Acacia is not monophyletic. Furthermore subgenera Acacia Vassal and Aculeiferum Vassal are sister taxa and neither appear closely related to subgenus Phyllodineae (DC.) Ser. Subgenera Acacia and Aculeiferum form a clade that is basal to a well-supported clade consisting of tribe Ingeae Benth. taxa, Faidherbia albida (Del.) A. Chev. and subgenus Phyllodineae. The series of relationships suggested by the cpDNA data contradicts previous investigations of the tribe. Possible explanations of this conflict are explored, and the taxonomic implications of the plastid DNA data set are considered.  相似文献   

7.
Understanding the relative evolutionary importance of parasites to different host taxa is problematic because the expression of disease and resistance are often confounded by factors such as host age and condition. The antibiotic-producing metapleural glands of ants are a potentially useful exception to this rule because they are a key first-line defense that are fixed in size in adults. Here we conduct a comparative analysis of the size of the gland reservoir across the fungus-growing ants (tribe Attini). Most attines have singly mated queens, but in two derived genera, the leaf-cutting ants, the queens are multiply mated, which is hypothesized to have evolved to improve colony-level disease resistance. We found that, relative to body size, the gland reservoirs of most attines are similar in size but that those of the leaf-cutting ants are significantly larger. In contrast, the size of the reservoir did not relate with the evolutionary transition from lower to higher attines and correlated at most only slightly with colony size. The results thus suggest that the relationship between leaf-cutting ants and their parasites is distinctly different from that for other attine ants, in accord with the hypothesis that multiple mating by queens evolved to improve colony-level disease resistance.  相似文献   

8.
Worldwide in distribution, the tribe Muscini comprises 21 accepted genera and about 350 species. In the present study, a cladistic analysis based upon adult morphological characters is carried out in order to discuss the monophyly of the tribe and its genera, the intergeneric relationships and, in some cases, also the intrageneric relationships. As a result, Muscini is supported as a monophyletic tribe sister-group of Stomoxyini. Except for Morellia Robineau-Desvoidy, Curranosia Paterson, and Eudasyphora Townsend, all the remaining genera are monophyletic. The results are dubious for Polietes Rondani, which was then provisionally kept unchanged. Morellia was broadened to include the Neotropical endemic genera Parapyrellia Townsend, Trichomorellia Stein, and Xenomorellia Malloch. Therefore, a new classification is proposed for Morellia in which it is divided into four subgenera: Morellia s.s. , Parapyrellia , Trichomorellia , and Xenomorellia . Furthermore, the previously proposed subgenus Dasysterna Zimin is given new status as a genus; however, as it is preoccupied by Dasysterna Dejean, the new replacement name Ziminellia nom. nov. is proposed herewith. Eudasyphora was found to be a paraphyletic group relative to Dasyphora Robineau-Desvoidy; both genera are hence synonymized, and Dasyphora is classified in three subgenera: Dasyphora s.s. , Eudasyphora , and Rypellia Malloch. The analysis demonstrated that the traditional classification of Musca Linnaeus into subgenera is artificial and, moreover, that the use of characters from male genitalia could be strongly informative for classifying the genus in phylogeny-supported species groups. Finally, the new classification proposal for Muscini recognizes 18 genera and, furthermore, two undescribed genus-ranked taxa are indicated.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 493–532.  相似文献   

9.
The histology and internal morphology of the male valve in a broad sample of Fritillary butterflies are examined. A large internal ridge to which the extensor of the valve muscle fastens is probably an autapomorphy for the tribe Argynnini. A large glandular pocket is found in the valves of all examined Heliconiinae, but is missing in other examined Nymphalidae. The pocket shows considerable variation between the higher taxa. In the higher Fritillaries (subtribe Argynnina) the pocket probably has an effective closing mechanism allowing the male to store a considerable amount of glandular secretion. It has earlier been suggested that the secreta from the pocket glands are transferred to the female during copulation, where they probably have an antiaphrodisiac effect, preventing other males from mating a once mated female. All examined male Fritillaries also have glands in the anellus, the terminal membrane between the valves. In Boloria these glands are extremely well developed and abundant, a condition that is probably an autapomorphy for that genus. The obtained characters are tested against a known phylogeny of the tribe Argynnini.  相似文献   

10.
The genus Auletobius in the Russian fauna is revised. Five species (A. egorovi, A. irkutensis, A. puberulus, A. sanguisorbae, and A. submaculatus) belonging to two subgenera are revealed. The distribution of these species in Russia is given. The data on the trophic associations of the species are summarized. Keys to the subtribes of the tribe Auletini, subgenera of the genus Auletobius, and species of the subgenus Auletobius s. str. are given. All the taxa are redescribed.  相似文献   

11.
To reveal evolutionary relationships and the rate of divergence of lanternfishes in the tribe Electronini (Myctophidae), analysis of sequence of cox 1 mtDNA fragment in three genera (12 species) of the tribe and in a closely related genus Myctophum (9 species) was performed. The results support the tribe monophyly; however, the divergence within it appeared to be not profound: genetic distances between genera and subgenera are smaller than between species within Myctophum and other genera of myctophids. In subgenera of Protomyctophum, species formation has obviously not completed since interspecies distances in them (0.5–4.7%) are comparable to estimates of intraspecific variation in other lanternfishes. Minimal genetic differences were found between species P. (Hierops) arcticum and P. (H.) subparallelum, whose ranges at the present time are isolated in the northern and southern hemispheres. After calibration of the molecular clock, the time of isolation of these two species can be dated to the Middle Pleistocene. Weak tribe diversification indicates its evolutionary youth, which can be related to the absence of efficient hydrographic barriers for isolation. The data obtained do not permit to consider tribe members as the most primitive in the family Myctophidae.  相似文献   

12.
We used nuclear ribosomal DNA internal transcribed spacer region (ITS 1 - 5.8S - ITS 2; ITS) sequences to generate the first phylogeny of Rubus based on a large, molecular data set. We sampled 57 taxa including 20 species of subgenus Rubus (blackberries), one to seven species from each of the remaining 11 subgenera, and the monotypic and closely related Dalibarda. In Rubus, ITS sequences are most informative among subgenera, and variability is low between closely related species. Parsimony analysis indicates that Rubus plus Dalibarda form a strongly supported clade, and D. repens may nest within Rubus. Of the subgenera with more than one species sampled, only subgenus Orobatus appears monophyletic. Three large clades are strongly supported: one contains all sampled species of nine of the 12 subgenera; another includes extreme Southern Hemisphere species of subgenera Comaropsis, Dalibarda, and Lampobatus; and a third clade consists of subgenus Rubus plus R. alpinus of subgenus Lampobatus. Rubus ursinus appears to be a hybrid between a close relative of R. macraei (subgenus Idaeobatus, raspberries) and an unidentified subgenus Rubus species. ITS sequences are generally consistent with biogeography and ploidy, but traditionally important morphological characters, such as stem armature and leaf type, appear to have limited phylogenetic value in Rubus.  相似文献   

13.
王红  曹诚一 《动物学研究》1993,14(2):118-127
本文对云南食植瓢虫族昆虫形态学,特别是跗爪基齿,上颚侧齿,雌、雄性外生殖器等性状的研究,讨论了本族的属间关系;应用分支系统学的原理和方法,对本族系统位置的研究进行了尝试。采用最大同步法对本族5个属8个性状状态进行了分支分析,其结果与传统分类结果有一定的差异。结论支持将食植瓢虫属分为3个亚属,其中2个为新亚属。  相似文献   

14.
What biological traits distinguish taxa susceptible to extinction from less susceptible taxa? Substantiated island biogeographic theory suggests that after insularization, small islands lose more species than do large islands. Thus, susceptible taxa are those now found on only large islands. The traits of susceptible taxa can thus be found by comparing the biology of species found only on large islands with those also found on small islands. The islands examined here are those of the Sunda Shelf, created as a result of the Holocene rise in sea levels of 120 m. We use four statistical comparisons: comparative analysis by (phylogenetically) independent contrasts (N = 8 contrasts at the subgeneric or deeper level), Spearman correlations, stepwise regression, and principle components analysis (N = 9 subgenera/genera). The genera and one subgenus considered are: Hylobates, Macaca, Nasalis, Nycticebus, Pongo, Presbytis, Symphalangus, Tarsius, and Trachypithecus. Traits of risk appear to be large body mass, low density, large annual home range, and low maximum latitude. Expected traits that did not correlate with susceptibility were low interbirth interval, high percent frugivory, high group mass, low altitudinal range, and small geographic range. The risky traits also apply to just the anthropoids (i.e., prosimians excluded). The risky traits are explained if susceptibility is induced by requirements for a large extent of habitat, a small population size, and specialization. These findings, which indicate that efficiency and plasticity of use of the environment separate susceptible from successful primate taxa, might be relevant to an understanding of hominoid evolution.  相似文献   

15.
The chromosomes of 26 taxa from Mexico of the tribes Passalini (three species) and Proculini (23 species) have been studied, increasing the karyotypically known species of the family Passalidae to 56. Karyotypic dynamism is high since the diploid number varies from 18 to 44 in the tribe Proculini. and from 25 to 31 in the tribe Passalini. In addition, supernumerary chromosomes, chromosome heteromorphism, translocations and possible sex multivalents have been found. These results contrast with the numerical conservatism found in related families of the superfamily Scarabaeoidea. However, both tribes are conservative with regard to sex determination, as all species of Proculini have male XY chromosomes whereas species of the Passalini have male XO chromosomes. It is postulated that differences in patterns shown by these two tribes are mainly due to population structure, because many species of Proculini are endemic to restricted areas of Meso and South America, favouring the settlement of karyotypic changes, whereas species of Passalini are distributed over large areas in the lowlands. It is also postulated that the ancestral karyotypic formula of the family is close to 12–14 pairs of autosomes although the ancestral male sex determination may be either XY or XO. At present only a weak relationship between morphological and karyotypic evolution has been found, which together with the marked numerical variability found within and between genera make it difficult to obtain phylogenetic conclusions from karyotypic results.  相似文献   

16.
Leaf epidermal (micromorphological and micromorphometric) features of the leaf blade were examined with light and scanning electron microscopy in 49 Central European natural populations of species belonging to subgenera Schedonorus and Drymanthele within the genus Festuca L. In addition, molecular biological (random amplified polymorphic DNA) studies were conducted on selected populations. The goal of the study was to reveal the degree of anatomical and genetic variability at the taxon and population level, as well as to determine the most important characters that allow differentiation of the taxa in these two subgenera. The anatomical variation was compared with the genetic distance between taxa. Investigated taxa exhibited great anatomic variability in terms of both qualitative (presence or absence, shape and appearance of various cell types) and quantitative characters (frequency and size of cells). Strong correlation was found between the genetic distance of populations and the frequency and size of silica cells in the costal zone of the epidermis, which indicates that silica cells are largely determined by the genetic background, regardless of varying environmental conditions. Our studies highlight that despite the high level of variability in anatomical features and genetic polymorphism, these fescue populations clearly segregate both in terms of epidermal structure and genetic constitution.  相似文献   

17.
Females of the parasitoid digger wasp species Liris niger hunt crickets as food for their future brood. The wasps paralyse the prey by injecting their venom directly into the CNS. The venom is produced in a gland consisting of two ramified glandular tubules terminating in a common reservoir. The reservoir contents enter the sting bulb via a ductus venatus. Secretory units of dermal gland type III line the two free gland tubules, the afferent ducts to the reservoir and the cap region within the reservoir. Secretion products of tubules reach the reservoir through the cuticle-lined central funnel. Secretory cells in the distal and middle parts of the tubules contain extensive rough endoplasmic reticulum and numerous electron-dense vesicles, whereas secretory cells of the afferent ducts and the cap region of the reservoir lack electron-dense vesicles and the endoplasmic reticulum is poorly developed. The secretory apparatus undergoes age-related changes. The secretory units in the venom gland tubules and inside the reservoir complete differentiation 1 day after imaginal ecdysis. After 30 days, massive autolytic processes occur in the secretory cells and in the epithelial cells of the reservoir. Analysis of the polypeptide composition demonstrates that the venom reservoir contains numerous proteins ranging from 3.4 to 200 kDa. A dominant component is a glycoprotein of about 90 kDa. In contrast the polypeptide composition of Dufour's gland is completely different and contains no glycoproteins. Comparison of the venom reservoir contents with the polypeptide pattern of venom droplets reveals that all of the major proteinaceous constituents become secreted. Thus the secreted venom contains exclusively proteins present in the soluble contents of the venom gland.  相似文献   

18.
Abstract The tribe Trypetimorphini, the genus Ommatissus , and its two subgenera and eleven species are redescribed or described as new. Evidence for the monophyly of both the genus and of the tribe to which it belongs is examined; it is concluded that while the genus is monophyletic, the monophyly of the tribe is in doubt. Keys for the separation of the three genera of the tribe and for all of the known species of Ommatissus are presented. A new subgenus of Ommatissus is described: O.(Opatissus) , with the type-species O.vietnamicus . Four new species are described: Ommatissus magribus from Morocco, O.kamerunus from Cameroon, O.natalensis from South Africa and O.vietnamicus from Vietnam. The 'Dubas bug', Ommatissus lybicus Bergevin, formerly regarded as a variety of O.binotatus Fieber, is raised to full species status. Trichoduchus is synonymized with Trypetimorpha resulting in the new combinations Trypetimorpha biermani Dammerman, T.china Wu and T.japonicus Ishihara. Trichoduchus japonicus Fennah is synonymized with Trypetimorpha japonicus Ishihara.  相似文献   

19.
《Insect Biochemistry》1985,15(3):385-390
The male accessory gland proteins of six Drosophila species belonging to three subgenera are compared with respect to their one- and two-dimensional electrophoretic properties. The species are: D. melanogaster, D. busckii, D. funebris, D. hydei, D. nigromelanica and D. virilis. In addition, the enhancing effect of the gland's secretion on ovulation is examined in heterospecific secretion injection experiments. Clear-cut differences in the electrophoretic protein patterns of the six species are observed on native and dissociative gels. The patterns reveal that the species differ with regard to the occurrence of some protein fractions and the relative abundance of others. The heterospecific secretions fail to induce ovulation in D. melanogaster. The results thus provide unequivocal evidence that the male accessory gland products in Drosophila are highly species-specific.  相似文献   

20.
The morphology and ultrastructure of the convoluted gland inside the venom reservoir of four species of social Vespidae are described. The cells of the venom gland (including the convoluted gland) can be divided into six groups: (1) epithelial cells, (2) glandular cells with the end apparatus secreting into the tubule inside the convoluted gland (internal or embedded tubule), (3) a continuous arrangement of glandular cells with the end apparatus secreting directly into the venom reservoir, (4) glandular cells that are loosely dispersed along the tubule lumen between the free tubules and the embedded tubule of the convoluted gland, (5) secretory cells of the free tubules and (6) duct cells. One kind of secretory cell, hitherto unknown and described in this paper (group 3), is characterized by the presence of a well-developed end apparatus, usually with enlarged extracellular spaces, but lacking the normally associated duct cells. The secretory cells contain several stacks of granular endoplasmic reticulum, but these are mainly concentrated in the middle of the cell. The basal half of the cells contains many lipid droplets. Although the function of the convoluted gland is not yet understood, an hypothesis is related to what is known of the function of reservoir secretory cells in solitary wasps. All wasp species studied showed the same organization of the convoluted gland, which clearly distinguishes their venom gland from that of Sphecidae.  相似文献   

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