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1.
Analysis of a considerable amount of data on the anatomy of 27 structures of the thorax in 96 genera of fleas (over 90% of the genera in the world fauna) shows that different flea taxa can be described based on 48 universal and specific characters, whose 203 states reflect the entire known diversity of the flea morphology. Of them, 26 characters with 96 states can be formulated based on universal terms; 22 universal characters with 88 states describe the proportions of the segments and their parts, and also proportions and shapes of their sclerites; 23 specific characters with 107 states describe the structure of the thoracic sclerites and ridges as well as the patterns of their junctions. Judging by the number of characters and their states, the most evolutionarily flexible structures in fleas are the mesosternite and its apodeme together with the upper part of the mesopleural rod. Homoplasies at various levels comprise less than half (40%) of all the character states in the thorax structure. The character states reflecting the phylogenetic closeness of taxa make up about 15%.  相似文献   

2.
The structure of 76 skeletal elements of adult fleas was analyzed, and the distribution of 114 characters with 446 character states over the body tagmata, segments, and morphofunctional complexes was investigated. Among them, 40% of the characters (40) and their states (163) describe the diversity of the structures of the frontal complex (including those of the head and prothorax), which is related to the specific features of flea parasitism. A large part of the characters (18) and their states (83) describe the structures of the nototrochanteral complex of the meso- and metathorax responsible for jumping. The total number of all types of homoplasies (258 states) is almost 1.8 times as great as the number of the states (145) that may be regarded as synapomorphies. The ancestral states (43) comprise a smaller portion of the total number. The proportion of the synapomorphic and homoplastic character states varies between the morphofunctional complexes.  相似文献   

3.
Alimentary activity and mortality was assessed in fleas Citellophilus tesquorum altaicus non-infected with Yersinia pestis and those with initial infection levels 50 and 100% during feeding on a non-specific host (white mice). The presence of the plague pathogen in fleas significantly stimulated their feeding activity, especially in females. No effect of infection on flea mortality was observed. At the same time, male fleas died more frequently than females.  相似文献   

4.
The paper continues the series of publications (Medvedev, 2015, 2016) devoted to the analysis of the structural features of fleas. In this part, the structural features of the thoracic setation are analyzed for the first time. Six characters with 53 states were distinguished in the chaetome of the pronotum, mesothorax, and metathorax. The analysis reveals some cases of the formation of externally similar states due to reduction or, by contrast, strengthening of the chaetome in some genera belonging to different superfamilies, in relation to the specific traits of parasitism. In spite of high variation in the number and arrangement of thoracic setae, some character states can be used as markers of flea taxa of the family and superfamily rank.  相似文献   

5.
Distribution of the ancestral, homoiologous, and convergent character states over the tagmata and morpho-functional complexes of the flea body in nine subfamilies of the Hystrichopsyllidae is analyzed. The analysis is based upon the states of 111 characters of 73 structures of 3 tagmata in the adult flea body. The homoiologous states (those arising in parallel in close flea infraorders) comprise 35%, the ancestral (the least specialized) ones, 16%, and the convergent ones, 13% of the total number of character states of all the 10 types. The greatest numbers of the ancestral character states in the Hystrichopsyllidae are found in the mesothorax (22.8%) and aedeagus (21.1%); the metathorax reveals 19.3%, and the head, 17.5% of the ancestral character states. The greatest number of homoiologous character states, 34.1% of the total number, is observed in the mesothoracal segment. Smaller fractions of the homoiologous character states are found in the head (24.6%) and metathorax (17.5%). Those character states which arise in the phylogenetically remote infraorders are considered convergent. The greatest number of convergent character states in the Hystrichopsyllidae (55.1%) is observed in the structure of the aedeagus.  相似文献   

6.
The species composition of fleas in the Moiynkum Desert (Chu-Talas interfluve) and indices of their domination on different hosts was established on the basis of long-term observations (1973–2000). The most significant and prolonged changes in the population density of mass flea species (Xenopsylla gerbilli minax and Coptopsylla lamellifer, parasites of the great gerbil) occur in association with changes of the population density of rodents. Changes in the population density of rodents are usually observed year after similar changes in the population density of hosts. The leading role in the transmission of the plague vector belongs to the flea X. gerbilli minax.  相似文献   

7.
The morphology of the male terminalia (uncus and subunci) was studied in 39 species of the subtribe Polyommatina (Lycaenidae). Traces of nine established characters were mapped on the molecular phylogeny of the subtribe proposed by Talavera et al. (2013). The ancestral character states for these morphological structures were established in Plebejus s. l. and Polyommatus s. l. According to the time calibration of the proposed molecular tree, the studied skeletal structures (uncus and subunci) evolved very slowly within the last million years. It was shown that the similar shape of the uncus and subuncus branches arose independently and underwent parallel morphological transformations. In particular, wide and, as a rule, ventrally directed uncus lobes arose independently in Polyommatus s. str., Alpherakya, Glabroculus, and Aricia. Yet, in various evolutionary lines of Polyommatina similar changes in the length ratio of the proximal and distal parts of the subunci as well as in the shape of their apical hooks were observed. The character states marking the groups Polyommatus s. str. and Aricia were established. The evolutionary changes in the uncus morphology were highly non-uniform in the various monophyletic lines of Polyommatina. As a result, representatives of some “old” lines have more specialized features of the uncus morphology in comparison with those belonging to “young” lines that retain ancestral character states. In Polyommatina, the transformation of the male terminalia was directed toward development of the most effective mechanism of female fixation during copulation. This goal was reached in similar ways in various evolutionary lines of Polyommatina, which explains numerous parallelisms in morphology of these structures.  相似文献   

8.
The host–parasite–vector relationship of Bartonella spp. system in wild carnivores and their fleas from northwestern Mexico was investigated. Sixty-six carnivores belonging to eight species were sampled, and 285 fleas belonging to three species were collected during spring (April–May) and fall (October–November) seasons. We detected Bartonella species in 7 carnivores (10.6%) and 27 fleas (9.5%) through either blood culture or PCR. Of the 27 Bartonella-positive fleas, twenty-two were Pulex simulans, three were Pulex irritans and one was Echidnophaga gallinacea. The gltA gene and ITS region sequences alignment revealed six and eight genetic variants of Bartonella spp., respectively. These variants were clustered into Bartonella rochalimae, Bartonella vinsonii subsp. berkhoffii and another genotype, which likely represents a novel species of Bartonella spp. Although experimental infection studies are required to prove the vector role of P. simulans, our results suggest that this flea may play an important role in the Bartonella transmission. The results indicated possible host-specific relationships between Bartonella genotypes and the families of the carnivores, but further studies are needed to verify this finding. The presence of zoonotic species of Bartonella spp. in wild carnivores raises the issue of their potential risk for humans in fragmented ecosystems.  相似文献   

9.
The flea fauna of the Ciscaucasia comprises 76 species, 13 of which are associated with birds and the rest, with mammals. Rodent parasites are the most numerous; fleas associated with carnivores, bats, and insectivores are less abundant. Fleas parasitize different species of birds of the orders Passeriformes, Anseriformes, Falconiformes, and Strigiformes. Among 41 flea genera known from the Caucasus, species of the genera Amalaraeus, Araeopsylla, Atyphloceras, Caenopsylla, Callopsylla, Doratopsylla, Paraneopsylla, Peromyscopsylla, Phaenopsylla, Tarsopsylla, and Wagnerina are absent in the Ciscaucasia. Only two subendemic species were revealed in the region; 33 flea species are distributed over the entire Ciscaucasia, while the distribution of others is limited to landscapes of one or two natural zones.  相似文献   

10.
Medvedev SG 《Parazitologiia》2001,35(4):291-306
The structure of pseudosetae, spinelets, and spines of combs (ctenidia) was studied by means of light and SE microscopy in 80% of genera and subgenera of the World fauna. It is found out that peculiarities of ctenidiae in the prothorax and in tergites of the abdomen are characteristics of families and infraorders of fleas. Some characters of ctenidiae found in certain flea genera are reductions and apparently caused by habitation in some extremal conditions. An absence of ctenidiae in the unfraorder Pulicomorpha is compensated by more developed posterior margin of prothorax and general abbreviation of all thoracal segments. Reasons of ctenidiae absence, which is observed in certain genera of the infraorders Ceratophyllomorpha, Pygiopsyllomorpha and Hystricopsillomorpha associated with the same hosts, is not clear. It is confirmed, that distance between ctenidiae in different flea species associated with the same species host species, however it is recovered, that this distance correlates with the diameter of most thin hair of host. In some flea species the distance between ctenidia spices in females is larger, than in males. It is found, that sexual dimorphism by this character may not be expressed in certain species of closely related species group of fleas. It is suggested that ctenidiae were present even in the common ancestor of fleas. The hypothesis on origin of spines and pseudosetae from setae of the posterior walls of toracal and abdominal segments in the common ancestor of fleas is proposed.  相似文献   

11.
【目的】分析云南省玉龙鼠疫疫源地野外鼠形动物寄生蚤丰盛度的影响因素。【方法】选取云南省玉龙鼠疫疫源地3个海拔区域,按4个季节进行野外捕鼠,捕获的鼠形动物用梳检法收集体表寄生蚤并在显微镜下分类鉴定。通过实际测量和实地观察相结合的方式收集潜在影响鼠形动物寄生蚤丰盛度的因素包括鼠形动物特征变量指标(如种类、年龄、性别、体长、体重)、环境和气象因子(如海拔、季节)等数据。采用EpiData 3.02软件建立数据库,在R软件下使用跨栏负二项分布回归分析鼠形动物寄生蚤丰盛度的影响因素。【结果】从捕获的884只鼠形动物中检获寄生蚤9种484头,以特新蚤指名亚种、方叶栉眼蚤、无值大锥蚤、云南栉眼蚤为主(86.16%)。回归分析显示: 2 700-3 000 m和3 000 m以上海拔鼠形动物染蚤概率较2 400-2 700 m分别增加1.27和3.72倍;湿度高于70%时,鼠形动物染蚤概率较湿度≤70%时减少41%;与齐氏姬鼠的染蚤概率相比,中华姬鼠的染蚤概率降低50%,大绒鼠的染蚤概率增加79%;体长超过104 mm的鼠形动物染蚤概率较体长≤104 mm的鼠形动物染蚤概率增加76%;气温高于15℃时,鼠形动物染蚤数量较温度≤15℃时降低67%;成年鼠形动物的染蚤数量较未成年鼠形动物的染蚤数量增加2.25倍;与春季相比,夏季的染蚤数量增加2.00倍,秋季的染蚤概率减少48%,冬季的染蚤概率和染蚤数量分别增加1.44和1.06倍。【结论】玉龙鼠疫疫源地野外鼠形动物寄生蚤以特新蚤指名亚种、方叶栉眼蚤、无值大锥蚤、云南栉眼蚤为优势蚤种。鼠形动物寄生蚤丰盛度与海拔、季节、气温、湿度等环境气象因子及鼠形动物种类、体长、年龄等鼠形动物特征变量密切相关。  相似文献   

12.
Results of analysis of the Caucasian fauna of fleas and their association with mammal and avian hosts are reported. The Caucasian fauna of potential flea hosts comprises about 130 species of mammals and about 470 species of birds. Most of the flea species in the Caucasian fauna (88 out of 155) parasitize rodents, 51 species of which are permanent hosts of different flea species; 13 flea species occur on 11 species of insectivores; 13 flea species, on 13 species of chiropterans; 14 flea species, on 20 species of carnivores. Only 2 flea species parasitize artiodactyles. 54 species of birds are permanent hosts of 23 species of fleas from 4 genera in the Caucasus. Ten types of ranges of flea species are distinguished; host associations of the Caucasian flea species from these groups are discussed. The greatest numbers of hosts from the families Cricetidae, Muridae, and Sciuridae are associated with fleas with Euro-Asian (extra-Siberian), European, Turanian, and Iranian ranges. Soricidae are known as hosts of flea species with European and Euro-Turanian ranges. Four major groups of flea taxa are represented in the Caucasian fauna. The distribution of the first group is determined by the influence of the palaeofauna of the ancient European continent in the early Cenozoic; that of the second group, by the influence of the fauna of the ancient Asian continent during the Paleogene and part of the Neogene; the third, by the influence of the fauna of southern Europe starting with the Miocene. The fourth group comprises the species which immigrated from northern Europe and Asia in the Late Neogene (2–3 mln years ago).  相似文献   

13.
Wiwaxia corrugata and the indisputable polychaetes of the Middle Cambrian Burgess Shale, particularly Canadia spinosa, have figured prominently in recent hypotheses about the early evolution of polychaete annelids. Based on similarities between the sclerites of Wiwaxia and the notochaetae of Canadia with the broad notochaetae (paleae) of Recent chrysopetalid polychaetes, these two fossil taxa have been variously treated as closely related to the most highly derived stem forms of the polychaete (and annelid) crown group or as members of a specific, Recent subgroup within Polychaeta, the order Phyllodocida. Chrysopetalidae is a member of Phyllodocida, which is part of the major polychaete clade Aciculata; the latter two taxa are distinguished by four and six well defined autapomorphic characters, respectively. The best preserved or otherwise appropriate fossils of Wiwaxia corrugata, Canadia spinosa and the other polychaetes of the Burgess Shale have been studied in detail in order to determine whether they possess any characters that could support the homology of wiwaxiid sclerites, canadiid notochaetae and chrysopetalid paleae. Most of these fossil taxa have significant autapomorphies but the specific characters of the Aciculata and Phyllodocida are entirely absent. It is demonstrated that constraining cladograms in such a manner that wiwaxiid sclerites, canadiid notochaetae and chrysopetalid paleae are homologous leads to results that are markedly unparsimonious. Furthermore, Canadia and the other polychaetes of the Burgess Shale cannot be referred to any extant subgroup within the Polychaeta and cannot be used to polarize character evolution within the annelid crown group. Apart from its dubious sclerites, Wiwaxia has no characters that could indicate any close relationship with Polychaeta or Annelida.  相似文献   

14.
Aim Spatial variation in the diversity of fleas parasitic on small mammals was examined to answer three questions. (1) Is the diversity of flea assemblages repeatable among populations of the same host species? (2) Does similarity in the composition of flea assemblages among populations of the same host species decay with geographical distance, with decreasing similarity in the composition of local host faunas, or with both? (3) Does the diversity of flea assemblages correlate with climatic variables? Location The study used previously published data on 69 species of small mammals and their fleas from 24 different regions of the Holarctic. Methods The diversity of flea assemblages was measured as both species richness and the average taxonomic distinctness of their component species. Similarity between flea assemblages was measured using both the Jaccard and Morisita–Horn indices, whereas similarity in the composition of host faunas between regions (host ‘faunal’ distance) was quantified using the Jaccard index. Where appropriate, a correction was made for the potentially confounding influence of phylogeny using the independent contrasts method. Results Flea species richness varied less within than among host species, and is thus a repeatable host species character; the same was not true of the taxonomic distinctness of flea assemblages. In almost all host species found in at least five regions, similarity in flea assemblages decreased with increases in either or both geographical and faunal distance. In most host species, the diversity of flea assemblages correlated with one or more climatic variable, in particular mean winter temperature. Main conclusions Spatial variation in flea diversity among populations of the same mammal species is constrained by the fact that it appears to be a species character, but is also driven by local climatic conditions. The results highlight how ecological processes interact with co‐evolutionary history to determine local parasite biodiversity.  相似文献   

15.
In “Oscillatoriales” cyanobacteria (Cyanophyceae), relatively simple and uniform morphology superimposes on high genetic diversity that impedes reliable identification. The system of Cyanobacteria set forth in Bergey’s Manual of Systematic Bacteriology-2001/Systematics of Archaea and Bacteria-2015 deals with operational taxa—form-genera (“larger” genera represented by strains) unlike true cyanophycean genera represented by species. Form-genera were established on morphological criteria shared with Cyanophyceae, although they were typified by Pasteur Culture Collection (PCC) strains. Despite being important in determinative cyanobacteriology, old diagnoses of form-genera should be reappraised because, in them: (i) vague and/or ephemeral morphological characters are considered taxonomically significant; (ii) phylogenetic character, such as 16S rRNA gene sequence (16S) is missing. We identified 32 “Oscillatoriales” strains from CALU collection (St. Petersburg University, Russia) basing on core morphology traits, 16S of PCC type strains, and 16S from GenBank database. We proposed that, in experimentally oriented and ecology oriented studies, unequivocal identification can be attained via triple match: streamlined form-genus diagnosis— 16S of PCC reference strain—GenBank most similar 16S. Additionally, we traced the phylogeny of “Oscillatoriales” form-genera via 16S clustering and HIP1 fingerprinting, and suggested that these operational taxa should be replaced with monophyletic assemblages. Nucleotide sequence data reported are available in the GenBank database under the accession numbers KX263921?KX263950.  相似文献   

16.
Transmission of Yersinia pestis to the long-tailed suslik (Citellus undulatus) by fleas (Citellophilus tesquorum) in the Tuva natural plague focus in different seasons (spring, summer, and autumn) was studied experimentally. Between feeding periods, insects were kept in an artificial nest under temperature and humidity closely corresponding to seasonal ones. The character of the agent transmission was estimated according to the fraction of fleas with the agent in the aggregated state (bacterial lumps, partial blocks of proventriculus), the fraction of blocked individuals, and the fraction of infected susliks and of those with the generalized form of infection. Seasonal dynamics of epizootic process of the Y. pestis transmission corresponded to the results obtained in the epizootic examination of the Tuva natural plague focus and reflected the dynamics of the epizootic process (increase-peak-decline). The activity of the formation of a proventriculus block in C. t. altaicus, the infection ability of the fleas, and the sensitivity of long-tailed Siberian susliks to Y. pestis were the highest in mid-summer (July-first ten days of August), during the period of epizooty activation in the focus. The maximal number of C. t. altaicus with the plague agent at the aggregated state was observed in the cold period, before wintering of insects and after their hibernation.  相似文献   

17.
In this work, embryos of selected Vicia species were examined to reveal the micromorphological characters that could have taxonomic significance. Experimental results show that morphological characters such as cotyledons shape and colour, radicle shape, colour and position, plumule colour and stipular parts attachments are variable and could be used for taxa identification in the genus Vicia. Numerical analysis based on 38 micromorphological characters was used to build a phenogram that indicated the relationships among the studied taxa. In addition, an identification key using embryo characters was prepared for Vicia species. The variability of embryo characters were discussed in the taxonomic context. Although the embryo characters have only limited phylogenetic signal for Vicia species, they might be used for their morphological delimitation.  相似文献   

18.
The structure of the abdominal and pregenital segments and genitalia of males was studied in Pyrellia rapax (Harris, 1780) and Musca autumnalis De Geer, 1776 (Muscidae, Muscini). The musculature of these species is compared with that in Musca domestica Linnaeus, 1758 (Muscidae) and Scathophaga stercoraria (Linnaeus, 1758) (Scathophagidae), previously investigated by O.G. Ovtshinnikova. Morphological analysis of sclerites and muscles of abdominal and pregenital segments and genitalia of males in Pyrellia rapax, Musca autumnalis, and M. domestica demonstrates processes of reduction in Musca as compared with P. rapax and S. stercoraria.  相似文献   

19.
Soleglad and Fet's (2003a) attempt to reconstruct the phylogeny of Recent (including extant) scorpions, the revised classification derived from it, and recent emendations, mostly published in their self‐edited online journal, Euscorpius, are deficient. Separate analyses of three independent matrices (morphology, 16S rDNA, 18S rDNA) were presented. In the morphological matrix, 52 binary and 10 tristate trichobothrial characters were replaced with one character comprising six ordered states representing trichobothrial “types”. The remaining matrix of 105 characters was further reduced to 33 “fundamental” characters (20% of the morphological dataset), the analysis of which appears to be the basis for the revised classification presented. The taxon sample for the morphological analysis included 14 supraspecific terminal taxa representing genera, the monophyly of only 7 (12.5%) of which has been confirmed. A composite terminal, assembled from the fragments of fossils that may not be confamilial let alone monophyletic, was created for the Palaeopisthacanthidae, employed as the primary outgroup for the analysis. Other important outgroup taxa, notably eurypterids, xiphosurans and other arachnids, were omitted entirely. The morphological characters presented contained numerous unjustifiable assumptions of character polarity and phylogenetic relationship. An approach to character coding, deliberately adopted to reduce “homoplasy”, biased the analysis towards a preconceived result. Structurally and topographically similar features in different taxa were explicitly assigned separate (often autapomorphic) states according to presumed phylogenetic relationships among the taxa in which they were observed. Putative “reversals” were coded as separate characters or states. Character transformation was forced by ordering, additive coding or Sankoff optimization through allegedly intermediate states for which there is no empirical evidence. Many characters were defined in a manner that demonstrates either a lack of understanding of, or disregard for, established methods and standards of morphological character coding. Some states display overlapping variation whereas others subsume variation that is not structurally or topographically similar. Polymorphic “states” were created for terminals with interspecific variation and unknown “states” for terminals that should have been scored unknown. Many characters were not evaluated for particular terminal taxa, but merely scored inapplicable although the structures and, consequently, the characters in question are present and therefore applicable to them. In view of the significant theoretical and empirical problems with the approach to cladistics taken by Soleglad and Fet, we find no justification for accepting either the results of their analyses or the revised classification derived from them. Pending the outcome of a rigorous phylogenetic analysis, published according to acceptable standards of scholarship in a peer‐reviewed journal, we revert to the suprageneric classification of Scorpiones reflected by the most recent peer‐reviewed, published treatments and reject all changes to the classification proposed by Soleglad, Fet and colleagues since 2001. We argue that an analysis and revised classification of the kind presented in various papers by these authors could not survive the peer‐review process of a mainstream scientific journal. The poor scholarship exemplified by these and other papers published in Euscorpius emphasize the importance of quality control associated with the emergent infrastructure of online publishing. A centralized register of taxa may be the only solution for ensuring quality control in the taxonomy of the future. © The Willi Hennig Society 2005.  相似文献   

20.
The structure of the ovipositor sclerites and muscles was studied in the tephritid fly Oxyna parietina (Linnaeus, 1758) inducing galls on the stems of Artemisia vulgaris. Adaptations of the ovipositor structure associated with changes of the oviposition substrate due to new larval habits are analyzed. The ovipositor muscles of Oxyna parietina are compared to those of Campiglossa. The genera Oxyna Robineau-Desvoidy, 1830 and Campiglossa Rondani, 1870 belong to the same genus-group of Tephritini, but differ in their host associations and oviposition habits: the larvae of Campiglossa plantaginis (Haliday, 1833) develop in the capitula of Aster tripolium and other asters (Asteraceae). The ovipositor sclerites and muscles are similar in the two genera. Progression of hemolymph into the membranous sheath of the ovipositor and protraction of the aculeus are necessary conditions for laying eggs into the capitula of Asteraceae (Campiglossa plantaginis), as well as for insertion of eggs into the axils of Artemisia leaves (Oxyna parietina). The most significant characters of Oxyna and Campiglossa include the presence of the hyaline apodeme and associated muscles MVM 6 and MVM 7 (instead of the median apodeme in Urophora). Thus, in other tephritid flies similarity in the structure of the ovipositor muscles may reflect similar morphofunctional adaptations to laying eggs into similar substrates, but similarity of Campiglossa and Oxyna in the structure of the ovipositor muscles is due to their close relations.  相似文献   

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