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1.
The medicinal genus Thottea (Aristolochiaceae) is represented in the Western Ghats, India, by eight species, seven of which are endemic to this region. In the present study, diversity in floral structure and organization of these eight species was analyzed from a systematic perspective. Floral morphology was thoroughly studied and discussed with emphasis on 16 qualitative and 11 quantitative characters. Statistical tools such as UPGMA cluster analysis, PCoA, PCA, and one-way ANOVA were used for elucidating species boundaries and inter-relationships. Significance of the selected qualitative and quantitative characters for species level systematics was revealed by the PCA and one-way ANOVA. Based on the nature of sepals (free/fused), two species groups were identified (first group with T. duchartrei and T. idukkiana, and the second group with the remaining six species). By considering the number and arrangement of stamens, yet another species grouping was proposed (one with T. abrahamii and T. dinghoui, and the other with the remaining six species). The UPGMA phenogram and the PCoA scatter plot clearly pointed out the existence of two species groups: the first group with T. abrahamii, T. barberi, T. dinghoui, T. ponmudiana, T. siliquosa, and T. sivarajanii, and the second one with T. duchartrei and T. idukkiana. With regard to the morphometric tools and the taxonomic key, it does not seem possible to distinguish T. abrahamii from T. dinghoui, and T. idukkiana from T. duchartrei.  相似文献   

2.
Three new species of the genus Trachyandra are described, T. hantamensis Boatwr. & J.C.Manning, T. kamiesbergensis Boatwr. & J.C.Manning and T. sanguinorhiza Boatwr. & J.C.Manning. These species form part of a group of morphologically similar species referred to here as the T. thyrsoidea group and are distinguished by their generally small stature, filiform leaves (except for T. tortilis), and simple or shortly branched racemes of patent flowers with maculate tepals. Many of the species in the group have roots that contain abundant anthraquinones, visible as a red substance below the outer skin of the roots, and which is soluble in alcohol, thus often staining herbarium papers purple. A synopsis of the eight species that comprise the T. thyrsoidea group is presented, with maps of each species and illustrations of those described as new.  相似文献   

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Chromosome counts of 9 species ofTaraxacum sect.Palustria are given. Five species were karyologically examined for the first time, viz.T. trilobifolium Hudziok,T. lissocarpum agg.,T. paucilobum Hudziok,T. subalpinum Hudziok andT. mendax, a new pentaploid species. Taxonomic and nomenclatural notes are added.  相似文献   

5.
Data on the detailed stratigraphic range of eight species of gastropod mollusks from the Upper Hauterivian of Ulyanovsk (Volga Region) are presented. A new genus, Trilemma, is established within the family Aporrhaidae. Two new species of this genus, T. russiense sp. nov. and T. striatocarinatum (Sinzow, 1880), are described.  相似文献   

6.
An introduction is presented to a taxonomic evaluation of rich cultivated and herbarium material of the genusTaraxacum from the Caucasus. Sources of the material, a survey of localities, and a preliminary account of the sections and species groups ofTaraxacum described from the Caucasus are given. The introduction is followed by a monograph ofT. sect.Porphyrantha, a section shown (contrary to the original conception and some literature data) to be endemic to the Caucasus. Six new species are described belonging to the section divided in two subsections, subsect.Porphyrantha and subsect.Haemantha, viz.T. pseudoporphyranthum, T. vepallidum, T. haemanthum, T. ignivomum, T. exstinctum andT. deminutum. Lectotypes are selected forT. porphyranthum Boiss. andT. pseudoroseum ?i?kin.  相似文献   

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A new species in the family Trichodoridae, from the rhizosphere of rice (Oryza sativa L.) in Northern Natal, South Africa, is described and illustrated. Trichodorus petrusalberti n. sp. resembles T. taylori De Waele, Mancini, Roca, and Lamberti, 1982, T. hooperi Loof, 1973, and T. complexus Rahman, Jairajpuri, and Ahmad, 1985, from which it is distinguished by the shape of the spicules. It is distinguished from the former two species by the nonthickened terminal cuticle in the males and by the shape and sclerotization of the vulval-vaginal region in lateral view in the females. Additional morphological details are given for T. sanniae Vermeulen and Heyns, 1985 and T. rinae Vermeulen and Heyns, 1985.  相似文献   

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The morphology of female genitalia is described for eight species of the genus Mellicta belonging to the M. aurelia species group from different localities within their ranges. The distinctive features, their variability, and possible use for species identification are assessed. It is shown that some characteristics of female genitalia can be used to clarify the position of species within the genus and, in some cases, to outline the species groups. Keys to species of the aurelia group are given.  相似文献   

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Subtribe Galipeinae (tribe Galipeeae, subfamily Rutoideae) is the most diverse group of Neotropical Rutaceae, with 28 genera and approximately 130 species. One of its genera is Almeidea, whose species are morphologically similar to those of the genus Conchocarpus. Species of Almeidea occur in the Atlantic Rain Forest of Eastern Brazil, with one species (Almeidea rubra) also present in Bolivia. The objective of this study was to perform a phylogenetic analysis of Almeidea, using a broader sampling of Galipeinae and other Neotropical Rutaceae, the first such study focused on this subtribe. To achieve this objective, morphological data and molecular data from the nuclear markers ITS-1 and ITS-2 and the plastid markers trnL-trnF and rps16 were obtained. Representatives of eight genera of Galipeinae and three genera of Pilocarpinae (included also in Galipeeae) and Hortia (closely related to Galipeeae) were used. Five species of Almeidea and seven of Conchocarpus were included, given the morphological proximity between these two genera. Individual (for each molecular marker) and combined phylogenetic analyses were made, using parsimony and Bayesian inference as optimization criteria. Results showed Galipeinae as monophyletic, with the species of Almeidea also monophyletic (supported by the presence of pantocolporate pollen) and nested in a clade with a group of species of Conchocarpus, a non-monophyletic group. Additionally, C. concinnus appeared in a group with Andreadoxa, Erythrochiton, and Neoraputia, other members of Galipeinae. As a result, Conchocarpus would be monophyletic only with the exclusion of a group of species related to C. concinnus and with the inclusion of all species of Almeidea with the group of species of Conchocarpus that includes its type species, C. macrophyllus. Thus, species of Almeidea are transferred to Conchocarpus, and the new combinations are made here.  相似文献   

13.
Toxoplasma gondii and Trichinella spiralis are important zoonotic pathogens with worldwide distributions. In Korea, several outbreaks of human toxoplasmosis and trichinellosis due to the consumption of infected wild animals have been reported. The purpose of this study was to determine the seroprevalence of T. gondii and T. spiralis infections in wild boars killed in Korea from December 2009 to October 2011. A total of 521 wild boars hunted in eight provinces were examined for antibodies to T. gondii and T. spiralis by using commercial ELISA kits. Overall, 25.1% of serum samples from individual boars were seropositive for T. gondii and 1.7% were seropositive for T. spiralis. Seropositive for T. gondii was found in the boars in all the eight provinces investigated and for T. spiralis in four provinces. This is the first report on the seroprevalence of T. gondii and T. spiralis infections in wild boars in Korea. The consumption of undercooked wild boar meat may expose humans to a high risk of infection.  相似文献   

14.
Single- and low-copy genes are less likely to be subject to concerted evolution. Thus, they are appropriate tools to study the origin and evolution of polyploidy plant taxa. The plastid 3-phosphoglycerate kinase gene (Pgk-1) sequences from 44 accessions of Triticum and Aegilops, representing diploid, tetraploid, and hexaploid wheats, were used to estimate the origin of Triticum petropavlovskyi. Our phylogenetic analysis was carried out on exon+intron, exon and intron sequences, using maximum likelihood, Bayesian inference and haplotype networking. We found the D genome sequences of Pgk-1 genes from T. petropavlovskyi are similar to the D genome orthologs in T. aestivum, while their relationship with Ae. tauschii is more distant. The A genome sequences of T. petropavlovskyi group with those of T. polonicum, but its Pgk-1 B genome sequences to some extent diverge from those of other species of Triticum. Our data do not support for the origin of T. petropavlovskyi either as an independent allopolyploidization event between Ae. tauschii and T. polonicum, or as a monomendelian mutation in T. aestivum. We suggest that T. petropavlovskyi originated via spontaneous introgression from T. polonicum into T. aestivum. The dating of this introgression indicates an age of 0.78 million years; a further mutation event concerning the B genome occurred 0.69 million years ago.  相似文献   

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Genetic studies on taste sensitivity, and bitter taste receptors (T2R) in particular, are an essential tool to understand ingestive behavior and its relation to variations of nutritional status occurring in ruminants. In the present study, we conducted a data-mining search to identify T2R candidates in sheep by comparison with the described T2R in cattle and using recently available ovine genome. In sheep, we identified eight orthologs of cattle genes: T2R16, T2R10B, T2R12, T2R3, T2R4, T2R67, T2R13 and T2R5. The in silico predicted genes were then confirmed by PCR and DNA sequencing. The sequencing results showed a 99% to 100% similarity with the in silico predicted sequence. Moreover, we address the chromosomal distribution and compare, in homology and phylogenetic terms, the obtained genes with the known T2R in human, mouse, dog, cattle, horse and pig. The eight novel genes identified map either to ovine chromosome 3 or 4. The phylogenetic data suggest a clustering by receptor type rather than by species for some of the receptors. From the species analyzed, we observed a clear proximity between the two ruminant species, sheep and cattle, in contrast with lower similarities obtained for the comparison of sheep with other mammals. Although further studies are needed to identify the complete T2R repertoire in domestic sheep, our data represent a first step for genetic studies on this field.  相似文献   

17.
Tylenchulus graminis n. sp. and T. palustris n. sp. are described and illustrated from broomsedge (Andropogon virginicus L.) and pop ash (Fraxinus caroliniana Mill.), respectively. T. graminis resembles T. furcus in having a distinct anus, but T. graminis second-stage juveniles (J2) do not have a bifid tail. T. semipenetrans does not have a perceptible anus. The mature female of T. graminis has a mucronate pointed terminus while T. semipenetrans has a smooth and round terminus. T. graminis males have wider stylet knobs and basal bulb and a longer tail than T. semipenetrans males. T. graminis J2 have a longer posterior body portion (without large fat globules) than T. semipenetrans J2. T. palustris resembles T. semipenetrans in having an undetectable anus but differs by the short and conoid mature female postvulval section. The male of T. palustris has larger stylet knobs and basal bulb than those of T. semipenetrans and a bluntly rounded tail terminus, which is tapered in T. semipenetrans. T. palustris differs from T. furcus and T. graminis in having an undetectable anus, by the conoid postvulval section of mature females, by the shorter and rounded tail of males, and the shorter J2 posterior body section without large fat globules. T. graminis and T. palustris are parasites of indigenous flora of Florida.  相似文献   

18.
The National Health and Nutrition Examination Survey (NHANES) evaluates the epidemiology in the U.S. population of certain infectious diseases, including Toxoplasma gondii (T. gondii), a protozoan parasite. This study aims to evaluate the seroprevalence of T. gondii -IgG antibodies using NHANES data to identify risk factors related to T. gondii. Using NHANES 2009–10, 2011–12, and 2013–14 cycles, univariate analyses and logistic regression models were conducted to determine the relationship between T. gondii seropositivity and various risk factors. Across the three cycles, 13.3% of participants tested positive for T. gondii-IgG seroprevalence, with a significant decrease in seroprevalence from the earlier to later cycles. 53.4% of individuals with positive serology were male. The probability of testing positive for T. gondii -IgG significantly increases between four and five times from the 18–29 age group to 70–79 age group. Seroprevalence also differed by ethnicity, with Latinos of any race having two times higher odds of testing positive for T. gondii compared to other ethnicities. Other sociodemographic factors were associated with lower odds of T. gondii seropositivity, including college education, higher household income, and health insurance. Most clinical conditions were not significantly associated with T. gondii, excluding depression, which was observed in 25% of patients positive for T. gondii-IgG. Further research on the influence of this parasite on infected individuals, including predispositions for risk-taking, is needed to better understand the relationship between Toxoplasma gondii, depression, and other mental illnesses.  相似文献   

19.
We employed four markers (two chloroplastic, one mitochondrial and one nuclear) to investigate whether Turbinaria ornata and Turbinaria conoides, two morphologically similar brown algae, are distinct species. The molecular data revealed reciprocal monophyly, thus confirming the two algae as discrete species. Nevertheless, taxonomical ambiguities remain. T. conoides is more morphologically variable than T. ornata. We identified an atypical T. conoides morphotype whose blade possesses intramarginal teeth, a morphological characteristic of the T. ornata group that is normally absent within T. conoides. The molecular data indicate, nonetheless, that this morphotype belongs genetically to the T. conoides group. Thus, the results cast doubt upon the validity of using intramarginal teeth for species diagnosis.  相似文献   

20.
Small juveniles (0.3–3 mg live weight) of three clam species, Tapes semidecussata Reeve, T. decussata L., and Mercenaria mercenaria L., were fed eight single-species algal diets at a range of temperatures. Nutritional value of the algae tested was in the order: Isochrysis aff galbana (T. ISO) = Skeletonema costatum >Chaetoceros calcitrans = Chroomonas salina = Thalassiosira pseudonana >Tetraselmis suecica >Phaeodactylum tricornutum >Chlamydomonas coccoides, when the same weight of these species was given in the diet to each clam species. Reasons for differences in nutritional value are discussed with reference to the biochemical content of the algae and the relative growth efficiency of the animals. Respiration rate, food cell clearance rate, and growth (as increase in organic weight) of M. mercenaria and T. semidecussata increased with temperature from 10 to 25 °C. Growth rates decreased at > 25 °C. T. decussata showed only a slightly increased growth response at > 15 °C.  相似文献   

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