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1.
Nine specimens of Apus affinis (J.E. Gray) were studied at Franceville, Haut-Ogooué Province, Republic of Gabon, for the presence of helminth parasites. Two cestode species of the family Dilepididae were recorded. Pseudangularia gonzalezi n. sp. is distinguished from the most similar species P. europaea Georgiev & Murai, 1993 by having elliptical cirrus-sac, longer vagina, longer rostellar sheath and greater diameter of suckers. An identification key to the species of the genus Pseudangularia Burt, 1938 is proposed. The present study is the first record of the genus Pseudangularia in the Afrotropical Region. Our study confirms that, in dilepidids with vaginal sclerites from swifts, breaking off the cirrus after copulation is a frequent phenomenon. The genus Gibsonilepis n. g. is erected as monotypic for Vitta swifti Singh, 1952 (originally described from the same host species in India) and Gibsonilepis swifti n. comb. is proposed. Gibsonilepis n. g. is distinguished from Vitta Burt, 1938 by its highly elongate rostellum, rostellar sheath much bigger than rostellum, relatively small rostellar hooks possessing strongly developed guard, disc-shaped suckers with weak peripheral musculature and flat or convex central part, long and well-expressed neck, highly lobed two-winged ovary (lobes rounded) and presence of a band consisting of rows of spine-like microtriches along posterior margin of each proglottis. This is the first record of G. swifti in the Afrotropical Region. The separation of G. swifti from the genus Vitta (parasites of swallows) suggests that, contrary to previous opinions, no dilepidid genera are shared by Apodidae (swifts) and Hirundinidae (swallows).  相似文献   

2.
Leucophyllum is one of the most remarkable endemic genera of North American deserts, with its simultaneous bloom of showy purple flowers. With Eremogeton and probably Capraria it forms part of tribe Leucophylleae. Leucophyllum has 16 species distributed mostly throughout the Chihuahuan and Tehuacán deserts. The three genera were sampled to investigate the phylogenetic relationships among them and to test the monophyly of Leucophyllum, based on plastid DNA (trnL‐F, rps16) and nuclear ribosomal (nr)DNA (internal transcribed spacer) sequences. Bayesian inference and maximum‐likelihood analyses confirmed that tribe Leucophylleae is monophyletic and formed by the three Neotropical genera. Separate (plastid DNA and nrDNA) and combined analyses retrieved Leucophyllum as paraphyletic, with L. mojinense as the sister species to the rest of the species in the tribe and Capraria spp. nested in one of two clades of Leucophyllum. Further monographic work is needed to identify the defining characters and limits of the genera, but we suggest that L. mojinense, with its different vegetative architecture, distinctive flowers and dissimilar distribution could be placed in its own genus. Each of the two clades in Leucophyllum could be considered a genus in its own right, and Capraria and Eremogeton can be recognized as independent genera, as they are at present. Leucophyllum ambiguum, the type species of the genus, belongs to one of the clades so the species of the other could be considered members of a new genus. The only diagnostic character detected at present is a ventricose corolla tube in one of the clades in Leucophyllum and a pressed corolla tube in the other. © 2013 The Linnean Society of London  相似文献   

3.
Secretary activities associated with the rostellum of adult Echinococcus granulosus were studied using histological, histochemical, and ultrastructural techniques, following rapid fixation of the cestodes in situ in the small intestine of the anaesthetised dog. Studies concentrated on the host-parasite interface from 30 to 35 days postinfection. At this time, contraction of the muscular rostellar pad appeared to be associated with extension of the apical rostellum into a crypt of Lieberkühn. Crypt invasion by the apical rostellum coincided with morphological changes and secretory activity in a group of modified tegumental cells, previously referred to as the rostellar gland. Secretory material, a cystine-rich protein, was observed in the nuclei and cytoplasm of the rostellar gland cells. Release of this material into the interface was seen only following crypt invasion by the apical rostellum. Although the mechanism of release is not clear, it may be analagous to holocrine secretory mechanisms, since apparent degeneration of the rostellar gland region was associated with secretion. Possible functional activities of the secretion associated with hook formation, nutrition, regulation, adhesion, and protection are discussed.  相似文献   

4.
Jeon, M.‐J., Song, J.‐H. & Ahn, K.‐J. (2012). Molecular phylogeny of the marine littoral genus Cafius (Coleoptera: Staphylinidae: Staphylininae) and implications for classification. —Zoologica Scripta, 41, 150–159. A phylogenetic analysis of the marine littoral genus Cafius Stephens is presented based on molecular characters. The data set comprised partial mitochondrial COI (910 bp), COII (369 bp), 12S rDNA (351–354 bp), 16S rDNA (505–509 bp) and nearly complete sequences of 18S rDNA (1814–1830 bp) for 37 species. Twenty‐seven Cafius species, representing five of six subgenera, two Remus Holme species, three Phucobius Sharp species, monotypic Thinocafius Steel and four outgroups were included. The sequences were analysed simultaneously by parsimony analysis in Tree Analysis Using New Technology (TNT) with traditional manual alignment, direct optimization (DO) in the program POY4 under a variety of gap costs and partitioned Bayesian analysis for the combined data. The genus Cafius and nearly all of its subgenera were not supported as being monophyletic. Instead, all analyses (parsimony trees, DO tree under equal weighting and Bayesian tree) showed monophyly of Cafius + Phucobius + Remus + Thinocafius (clade Z) and all seven nested clades (A–G). However, the phylogenetic relationships among clades A–G differed among the analyses. The genus Phucobius was recovered as a monophyletic group within Cafius. The genus Remus was not monophyletic but formed a clade with C. rufescens Sharp and C. rufifrons Bierig within Cafius. The genus Thinocafius formed a clade with C. caviceps Broun, C. litoreus (Broun) and C. quadriimpressus (White) within Cafius. We propose new concepts for the genus Cafius and its related genera, and the seven nested clades.  相似文献   

5.
To more confidently assess phylogenetic relationships among astome ciliates, we obtained small subunit (SSU) rRNA sequences from nine species distributed in six genera and three families: Almophrya bivacuolata, Eudrilophrya complanata, Metaracoelophrya sp. 1, Metaracoelophrya sp. 2, Metaracoelophrya intermedia, Metaradiophrya sp., Njinella prolifera, Paraclausilocola constricta n. gen., n. sp., and Paraclausilocola elongata n. sp. The two new species in the proposed new clausilocolid genus Paraclausilocola n. gen. are astomes with no attachment apparatus, two files of contractile vacuoles, and an arc-like anterior suture that has differentiations of thigmotactic ciliature on the anterior ends of the left kineties of the upper surface. Phylogenetic analyses were undertaken using neighbor-joining, Bayesian inference, maximum likelihood, and maximum parsimony. The nine species of astomes formed a strongly supported clade, showing the subclass Astomatia to be monophyletic and a weakly supported sister clade to the scuticociliates. There were two strongly supported clades within the astomes. However, genera assigned to the same family were found in different clades, and genera assigned to the same order were found in both clades. Thus, astome taxa appear to be paraphyletic when morphology is used to assign species to genera.  相似文献   

6.
Phylogeny of the genus Pythium is analyzed based on sequences of the large subunit ribosomal DNA D1/D2 region and cytochrome oxidase II gene region of Pythium isolates and comprehensive species of related taxa belonging to the Oomycetes. The phylogenetic trees show that the genus Pythium is a highly divergent group and divided into five well- or moderately supported monophyletic clades. Each clade is characterized by sporangial morphology such as globose, ovoid, elongated, or filamentous shapes. Based on phylogeny and morphology, the genus Pythium (s. str.) is emended, and four new genera, Ovatisporangium, Globisporangium, Elongisporangium, and Pilasporangium, are described and segregated from Pythium s. lato.  相似文献   

7.
A molecular phylogenetic hypothesis is presented for the anoplocephaline cestodes of placental mammals based on sequence data from the mitochondrial cytochrome c oxidase I (COI) gene, the nuclear-encoded 28S rRNA gene and the internal transcribed spacer region I of rRNA (ITS1). The material consists of 35 species representing nine genera of cestodes, with emphasis on taxa parasitising rodents and lagomorphs in the Holarctic region. The resulting phylogenies show considerable disagreement with earlier systematic and phylogenetic hypotheses derived from morphology. Specifically, the results contradict the view of uterine morphology being the primary determinant of deeper phylogenetic splits within Anoplocephalinae. Also, the role of genital duplication as a means of generic divergence was not found to follow consistently the pattern suggested by earlier hypotheses. Colonisation of novel host lineages has evidently been the predominant mode of diversification in anoplocephaline cestodes of placental mammals; evidence for phyletic co-evolution was obscure. The phylogenies consistently distinguished a large monophyletic group including all species from arvicoline rodents (voles and lemmings), primarily representing the genera Anoplocephaloides Baer, 1923 and Paranoplocephala Lühe, 1910. Phylogenetic relationships within the “arvicoline clade” of cestodes were generally poorly resolved. Consistent support for nodes above and below the unresolved polytomy indicates a rapid radiation involving a nearly simultaneous diversification of many lineages, a scenario also proposed for the arvicoline hosts.  相似文献   

8.
A previously unrecognised species of hymenolepidid cestode attributable to Vampirolepis Spassky, 1954 is described based on specimens from the common noctule bat Nyctalus noctula (Schreber) (Chiroptera: Vespertilionidae) from southeastern Kazakhstan (Dzungarian Alatau). Specimens of Vampirolepis kulkinae n. sp. differ from the morphologically similar congeners based on the number, size and shape of the rostellar hooks. The new species is further distinguished from additional cestodes attributed to Vampirolepis (sensu lato) by the arrangement of the testes in one row, egg structure (i.e. thin outer coat and emryophore without polar filaments) and the relative position and length of the cirrus-sac. This is the first species of the genus Vampirolepis described from Kazakhstan.  相似文献   

9.
Klopfstein, S., Quicke, D. L. J., Kropf, C. & Frick, H. (2011) Molecular and morphological phylogeny of Diplazontinae (Hymenoptera, Ichneumonidae). —Zoologica Scripta, 40, 379–402. Parasitoid wasps are among the most species rich and at the same time most understudied of all metazoan taxa. To understand their diversification and test hypotheses about their evolution, we need robust phylogenetic hypotheses. Here, we reconstruct the phylogeny of the subfamily Diplazontinae using four genes and 66 morphological characters both in separate analyses and in a total evidence approach. The resulting phylogeny is highly resolved, with most clades supported by multiple independent data partitions. It contains three highly supported genus groups, for which we suggest morphological and behavioural synapomorphies. The placement of some of the genera, especially Xestopelta Dasch, is unexpected, but also supported by morphology. Most of the genera are retrieved as monophyletic, with the exception of the morphologically diverse genus Syrphoctonus Förster. We split this genus into three genera, including Fossatyloides gen. n., to restore the phylogeny–classification link. Conflict between the morphological and the molecular topology was mostly resolved in favour of the molecular partition in the total evidence approach. We discuss reasons for this finding, and suggest strategies for future taxon and character sampling in Diplazontinae.  相似文献   

10.
Haukisalmi, V., Wickström, L. M., Henttonen, H., Hantula, J. & Gubányi, A. (2004). Molecular and morphological evidence for multiple species within Paranoplocephala omphalodes (Cestoda, Anoplocephalidae) in Microtus voles (Arvicolinae). —Zoologica Scripta, 33, 277–290. The present study was designed to test the hypothesis that the anoplocephalid cestode Paranoplocephala omphalodes (Hermann, 1783), a Holarctic parasite of Microtus voles, is a complex of host‐specific species, rather than a single host‐generalist species, using uni‐ and multivariate morphometrics and DNA sequence data from the mitochondrial cytochrome oxidase I gene. The phylogenetic methods applied to the mtDNA sequence data showed consistently that the cestodes morphologically recognizable as P. omphalodes include four well‐supported monophyletic groups, representing at least three distinct, largely host‐specific species. Multivariate morphometrics (discriminant analysis) successfully distinguished the four main mtDNA clades of P. omphalodes‐like cestodes. The true P. omphalodes is shown to be a parasite of Microtus arvalis, M. agrestis and Clethrionomys glareolus in Europe. Microtus oeconomus harbours two host‐specific, allopatric and possibly conspecific clades, one with a Holarctic and another with an (eastern) Beringian (Alaskan) distribution. The eastern Beringian endemic M. miurus is also parasitized with a host‐specific, morphologically divergent species of Paranoplocephala. The cestode clades recognized in M. oeconomus and M. miurus represent 2–3 undescribed species. Molecular phylogenetic analyses supported the monophyly of the ‘northern clade’ of Paranoplocephala spp., an assemblage including P. kalelai from Clethrionomys spp., P. macrocephala from Microtus spp. and all clades of P. omphalodes‐like cestodes except those representing the true P. omphalodes from Europe. The intra‐ and interspecific phylogeny within the northern clade is compared tentatively with the known evolutionary history of the hosts.  相似文献   

11.
Tsui CK  Sivichai S  Berbee ML 《Mycologia》2006,98(1):94-104
Three genera of asexual, helical-spored fungi, Helicoma, Helicomyces and Helicosporium traditionally have been differentiated by the morphology of their conidia and conidiophores. In this paper we assessed their phylogenetic relationships from ribosomal sequences from ITS, 5.8S and partial LSU regions using maximum parsimony, maximum likelihood and Bayesian analysis. Forty-five isolates from the three genera were closely related and were within the teleomorphic genus Tubeufia sensu Barr (Tubeufiaceae, Ascomycota). Most of the species could be placed in one of the seven clades that each received 78% or greater bootstrap support. However none of the anamorphic genera were monophyletic and all but one of the clades contained species from more than one genus. The 15 isolates of Helicoma were scattered through the phylogeny and appeared in five of the clades. None of the four sections within the genus were monophyletic, although species from Helicoma sect. helicoma were concentrated in Clade A. The Helicosporium species also appeared in five clades. The four Helicomyces species were distributed among three clades. Most of the clades supported by sequence data lacked unifying morphological characters. Traditional characters such as the thickness of the conidial filament and whether conidiophores were conspicuous or reduced proved to be poor predictors of phylogenetic relationships. However some combinations of characters including conidium colour and the presence of lateral, tooth-like conidiogenous cells did appear to be predictive of genetic relationships.  相似文献   

12.
We studied the distribution patterns and microhabitat use in gastrointestinal helminths of the shrews Sorex araneus and S. caecutiens in Finland. The distribution of species prevalences was bimodal, and in S. araneus the abundance (mean intensity) was positively associated with commonness (prevalence), as assumed by the core-satellite species hypothesis (Hanski 1982). However, the positive correlation between prevalence and intensity was observed only when the effects of helminth body size and taxonomic group (cestodes vs nematodes) on intensity were controlled for. The nematodes of the genus Longistriata occurred predictably as core species, whereas the identity of the core cestodes was more variable between host species and regions. Helminth body size and taxonomic group were not related to the degree of aggregation in shrew populations, but helminth body size seemed to explain the differences in the distribution patterns of helminths between shrews and voles. The core species did not show more segregation in microhabitat use than randomly selected species. In fact, the two core nematodes showed largely overlapping intestinal distributions. We conclude that linear intestinal space is not a key resource for shrew nematodes, but it may be for shrew cestodes.  相似文献   

13.
Two new species of hymenolepidid cestodes belonging to the genus Armadolepis Spassky, 1954 are described from dormice (Gliridae) from the southern East European Plain and the northwestern Caucasus, Russia. Armadolepis (Bremserilepis) longisoma n. sp., with a rudimentary, unarmed rostellar apparatus is described from the fat dormouse Glis glis (Linnaeus) from the Republic of Adygeya, Russia. Additionally, A. (Armadolepis) dryomi n. sp., characterised by a well-developed rostellar apparatus and armed rhynchus is described from the forest dormouse Dryomys nitedula Pallas from Rostov Oblast’, Russia. Armadolepis (Bremserilepis) longisoma n. sp. differs from A. (Bremserilepis) myoxi (Rudolphi, 1819) in having a substantially longer strobila and cirrus-sac, wider scolex and ovary and larger rostellar pouch and testes. Armadolepis (Armadolepis) dryomi n. sp. is distinguishable from A. (Armadolepis) spasskii Tenora & Baru?, 1958, A. (Armadolepis) jeanbaeri Makarikov, 2017 and A. (Armadolepis) tenorai Makarikov, 2017 in having a substantially longer and wider strobila, and larger rostellar pouch and cirrus-sac. Furthermore, A. dryomi n. sp. can be distinguished from its congeners by the number and size of rostellar hooks and the arrangement of the testes. Phylogenetic affinities of Armadolepis were studied for the first time using partial sequences of the nuclear ribosomal 28S DNA gene. Phylogenetic analysis strongly supported the status of Armadolepis as a separate genus belonging to the “Rodentolepis clade”.  相似文献   

14.
Ochromonas sensu lato is the largest genus in the Chrysophyceae, containing over 100 names. Ochromonas species are biflagellate, naked, plastid‐bearing single cells, distinguished from loricate, scaled, colonial and colorless genera. Most, if not all, species of Ochromonas are mixotrophic, i.e., they photosynthesize but they also engulf bacteria and other small prey. Preliminary evidence from SSU rRNA sequences show that Ochromonas is a polyphyletic genus. Ochromonas tuberculata is the most distinct from all other Ochromonas species. The other Ochromonas species (examined thus far) are scattered in three clades. For example, O. danica and O. sphaerocystis are sister to Poterioochromonas stipitata and P. malhamensis. Four additional species (identified by light microscopy as O. elegans Doflein, O. globosa Skuja, O. ovalis Dolfein, O. sociabilis Pringheim) have SSU rRNA sequences identical to P. malhamensis. Of these, only O. sociabilis has been transferred to Poterioochromonas. Thus, at least some species may be synonymous with others. Two clades of marine species are also known, one containing coastal species and the other containing open ocean species. A number of genera (some also polyphyletic) are interspersed amongst the Ochromonas species (e.g., Chrysolepidomonas, Chrysonephele, Chrysoxys, Cyclonexis, Dinobryon, Epipyxis, Uroglena, Uroglenopsis). The goal of this research (just beginning) is to establish a monophyletic Ochromonas, probably by assigning some species to other genera (existing or new). One major problem is that the type species, O. triangulata Vysotskii, hasn't been observed in over 100 years, and it is unclear which of several clades of Ochromonas contains the type. Results will be discussed.  相似文献   

15.
A phylogenetic analysis was carried out on rDNA of 45 species of anoplocephaline cestodes from marsupial hosts. The exclusively Australasian genera Progamotaenia Nybelin, 1917, Triplotaenia Boas, 1902, Paramoniezia Maplestone & Southwell, 1923 and Phascolotaenia Beveridge, 1976 formed a monophyletic clade, and the previously suggested relationship between the Australasian species of the cosmopolitan genus Bertiella Stiles & Hassall, 1902 and species of Progamotaenia was supported. A low degree of phyletic co-evolution was detected within endemic Australasian clades. Colonisation rather than co-speciation appeared to be the principal means of diversification within the Australasian anoplocephaline radiation. The clade of bile duct-inhabiting Progamotaenia species emphasises the role of microhabitat rather than host species as a driver of speciation. Triplotaenia undosa Beveridge, 1976 described from a wide variety of macropodid hosts was found to be polyphyletic and a proposition was made to resurrect Wallabicestus Schmidt, 1975, with W. ewersi Schmidt, 1975 as the type-species and including W. ualabati (Beveridge, 2009) n. comb. [previously Progamotaenia ualabati Beveridge, 2009].  相似文献   

16.
Thirty-three species of Clerodendrum s.l. and five outgroup genera were included in a sequence analysis of internal transcribed spacers of the nuclear ribosomal DNA. The results of the cladistic analysis were compared to and combined with cpDNA restriction site data from a previous study. All molecular data identified four major clades within Clerodendrum s.l. and showed the genus to be polyphyletic. Clerodendrum s.s., minus Konocalyx and Cyclonema, is monophyletic and the genus should be restricted to this group. Cyclonema and Konocalyx form a clade distinct from Clerodendrum s.s., which has been recognized as Rotheca Raf.  相似文献   

17.
Ainscough, B.J., Breinholt, J.W., Robison, H.W. & Crandall, K.A. (2013). Molecular phylogenetics of the burrowing crayfish genus Fallicambarus (Decapoda: Cambaridae). —Zoologica Scripta, 42, 306–316. The crayfish genus Fallicambarus contains 19 species of primary burrowing freshwater crayfish divided into two distinct subgenera. We test current hypotheses of the phylogenetic relationships among species within the genus as well as the monophyly of the genus. Our study samples all 19 species for five gene regions (both nuclear and mitochondrial) to estimate a robust phylogenetic hypothesis for the genus. We show that the genus is not a monophyletic group. The subgenus Creaserinus does fall out as a monophyletic group, but distinct from the subgenus Fallicambarus. The subgenus Fallicambarus appears to be monophyletic with the exception of the species Procambarus (Tenuicambarus) tenuis, which falls in the midst of this subgenus suggesting that it might be better classified as a Fallicambarus species. We also show that the species Fallicambarus fodiens is a species complex with distinct evolutionary lineages that are regionalized to different geographic areas.  相似文献   

18.
Hymenolepidid cestodes of synanthropic rodents represent a risk for public health. In order to describe the occurrence of hymenolepidids in children and the role of rodents as a potential source of infection, we conducted a morphological and molecular survey on cestodes in two rural villages from Yucatan, Mexico. One hundred and thirty-five stool samples from children (64 from Paraíso and 71 from Xkalakdzonot), 233 Mus musculus (159 from Paraíso and 74 from Xkalakdzonot) and 125 Rattus rattus (7 from Paraíso and 118 from Xkalakdzonot) were analyzed for the presence of cestodes. Three hymenolepidid species were identified morphologically: Hymenolepis nana in 7.8% of children from Paraíso, Hymenolepis microstoma in 4.4% of M. musculus from Paraíso and Hymenolepis diminuta in 15.3% of R. rattus from Xkalakdzonot. The molecular characterization and phylogenetic analysis based on mitochondrial cytochrome c subunit 1 (CO1) gene and ribosomal internal transcribed spacer 1 (ITS1) region, confirmed the identity of the three cestodes isolated from Yucatan. Phylogeny of the CO1 gene identified intraspecific genetic differences within H. nana ranging from 0 to 5%, in H. microstoma from 0 to 0.4%, and in H. diminuta ranged from 0 to 6.5% which suggests, the presence of complex species within H. nana and H. diminuta infecting humans and rodents, as reported by other authors. Based on the morphological and molecular results, and the epidemiological evidence, infections with H. nana suggest a non-zoonotic transmission; however, the presence of H. microstoma and H. diminuta in synanthropic rodents serve as a possible source for human infection.  相似文献   

19.
Impatiens L. is one of the largest angiosperm genera, containing over 1000 species, and is notorious for its taxonomic difficulty. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total evidence approach. Forty‐six morphological characters, mainly obtained from our own investigations, are combined with sequence data from three genetic regions, including nuclear ribosomal ITS and plastid atpB‐rbcL and trnL‐F. We include 150 Impatiens species representing all clades recovered by previous phylogenetic analyses as well as three outgroups. Maximum‐parsimony and Bayesian inference methods were used to infer phylogenetic relationships. Our analyses concur with previous studies, but in most cases provide stronger support. Impatiens splits into two major clades. For the first time, we report that species with three‐colpate pollen and four carpels form a monophyletic group (clade I). Within clade II, seven well‐supported subclades are recognized. Within this phylogenetic framework, character evolution is reconstructed, and diagnostic morphological characters for different clades and subclades are identified and discussed. Based on both morphological and molecular evidence, a new classification outline is presented, in which Impatiens is divided into two subgenera, subgen. Clavicarpa and subgen. Impatiens; the latter is further subdivided into seven sections.  相似文献   

20.
Based on 28 taxa, including six species of Phylloporia, and respectively one representative of 17 genera of the Hymenochaetales, a phylogenetic analysis of a region of the large subunit of the nuclear encoded ribosomal DNA was performed. Molecular sequence data as well as morphological and anatomical features show the genus to be monophyletic. Next related to Phylloporia is Fulvifomes. The phylogenetic relationships of Phylloporia are discussed. In addition the genus Phylloporia is monographed; 12 species are accepted and described with a key.  相似文献   

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