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1.
Hemibrycon sanjuanensis, new species, is described from the upper San Juan River drainage, Pacific versant, Colombia. It is distinguished from Hemibrycon boquiae, Hemibrycon brevispini, Hemibrycon cairoense, Hemibrycon colombianus, Hemibrycon mikrostiktos, Hemibrycon metae, Hemibrycon palomae, Hemibrycon rafaelense and Hemibrycon tridens by the presence of a circular or oblong humeral spot that is located two scales posterior to the opercle (vs. 3–4 scales in Hemibrycon palomae, Hemibrycon rafaelense, Hemibrycon brevispini and Hemibrycon cairoense, and 0–1 scales, in Hemibrycon metae and Hemibrycon boquiae). It further differs from Hemibrycon colombianus in having a round or oblong humeral spot (vs. rectangular). It differs from Hemibrycon beni, Hemibrycon dariensis, Hemibrycon divisorensis, Hemibrycon helleri, Hemibrycon huambonicus, Hemibrycon inambari, Hemibrycon jabonero, Hemibrycon jelskii, Hemibrycon mikrostiktos, Hemibrycon polyodon, Hemibrycon quindos, Hemibrycon raqueliae, Hemibrycon santamartae, Hemibrycon surinamensis, Hemibrycon taeniurus, Hemibrycon tridens, and Hemibrycon yacopiae in having melanophores on the posterior margins of the scales along the sides of body (vs. lacking melanophores on margins of scales along entire length of the sides of body). The new species differs from all congeners mentioned above in having, among other features, six teeth in the outer premaxillary row arranged in a straight line (vs. five or fewer teeth not arranged in straight line except Hemibrycon cairoense with two to six teeth in the outer premaxillary row).  相似文献   

2.
The tiger beetle assemblage of the wetlands of La Mancha (central Spain) comprises nine species: Calomera littoralis littoralis, Cephalota maura maura, Cephalota circumdata imperialis, Cephalota dulcinea, Cicindela campestris campestris, Cicindela maroccana, Cylindera paludosa, Lophyra flexuosa flexuosa, and Myriochila melancholica melancholica. This assemblage represents the largest concentration of tiger beetles in a single 1º latitude / longitude square in Europe. General patterns of spatial and temporal segregation among species are discussed based on observations of 1462 specimens registered during an observation period of one year, from April to August. The different species of Cicindelini appear to be distributed over space and time, with little overlapping among them. Three sets of species replace each other phenologically as the season goes on. Most of the species occupy drying or dried salt lakes and salt marshes, with sparse vegetation cover. Spatial segregation is marked in terms of substrate and vegetation use. Calomera littoralis and Myriochila melancholica have been observed mainly on wet soils; Cephalota circumdata on dry open saline flats; Cephalota dulcinea and Cylindera paludosa in granulated substrates with typical halophytic vegetation; Cephalota maura is often present in man-modified areas. Cephalota circumdata and Cephalota dulcinea are included as species of special interest in the list of protected species in Castilla–La Mancha. Conservation problems for the Cicindelini assemblage arise from agricultural activities and inadequate use of sport vehicles. Attempts at restoring the original habitat, supressing old semi-industrial structures, may affect the spatial heterogeneity of the lakes, and have an effect on Cicindelinae diversity.  相似文献   

3.
The Madagascar periwinkle ( Catharanthus roseus in the family Apocynaceae) is an important medicinal plant and is the source of several widely marketed chemotherapeutic drugs. It is also commonly grown for its ornamental values and, due to ease of infection and distinctiveness of symptoms, is often used as the host for studies on phytoplasmas, an important group of uncultivated plant pathogens. To gain insights into the characteristics of apocynaceous plastid genomes (plastomes), we used a reference-assisted approach to assemble the complete plastome of C . roseus , which could be applied to other C . roseus -related studies. The C . roseus plastome is the second completely sequenced plastome in the asterid order Gentianales. We performed comparative analyses with two other representative sequences in the same order, including the complete plastome of Coffea arabica (from the basal Gentianales family Rubiaceae) and the nearly complete plastome of Asclepias syriaca (Apocynaceae). The results demonstrated considerable variations in gene content and plastome organization within Apocynaceae, including the presence/absence of three essential genes (i.e., accD, clpP, and ycf1) and large size changes in non-coding regions (e.g., rps2-rpoC2 and IRb-ndhF). To find plastome markers of potential utility for Catharanthus breeding and phylogenetic analyses, we identified 41 C . roseus -specific simple sequence repeats. Furthermore, five intergenic regions with high divergence between C . roseus and three other euasterids I taxa were identified as candidate markers. To resolve the euasterids I interordinal relationships, 82 plastome genes were used for phylogenetic inference. With the addition of representatives from Apocynaceae and sampling of most other asterid orders, a sister relationship between Gentianales and Solanales is supported.  相似文献   

4.
Soil-transmitted helminths are parasitic nematodes that inhabit the human intestine. These parasites, which include two hookworm species, Ancylostoma duodenale and Necator americanus, the whipworm Trichuris trichiura , and the large roundworm Ascaris lumbricoides , infect upwards of two billion people and are a major cause of disease burden in children and pregnant women. The challenge with treating these diseases is that poverty, safety, and inefficient public health policy have marginalized drug development and distribution to control infection in humans. Anthelmintics (anti-worm drugs) have historically been developed and tested for treatment of non-human parasitic nematodes that infect livestock and companion animals. Here we systematically compare the in vitro efficacy of all major anthelmintic classes currently used in human therapy (benzimidazoles, nicotinic acetylcholine receptor agonists, macrocyclic lactones, nitazoxanide) against species closely related to human parasitic nematodes-Ancylostoma ceylanicum, Trichuris muris , and Ascaris suum --- as well as a rodent parasitic nematode used in veterinary drug discovery, Heligmosomoides bakeri , and the free-living nematode Caenorhabditis elegans. Extensive in vitro data is complemented with single-dose in vivo data in three rodent models of parasitic diseases. We find that the effects of the drugs in vitro and in vivo can vary greatly among these nematode species, e.g., the efficacy of albendazole is strong on A. ceylanicum but weak on H . bakeri . Nonetheless, certain commonalities of the in vitro effects of the drugs can be seen, e.g., nitazoxanide consistently shows an all-or-nothing response. Our in vitro data suggest that further optimization of the clinical efficacy of some of these anthelmintics could be achieved by altering the treatment routine and/or dosing. Most importantly, our in vitro and in vivo data indicate that the hookworm A. ceylanicum is a particularly sensitive and useful model for anthelmintic studies and should be incorporated early on in drug screens for broad-spectrum human soil-transmitted helminth therapies.  相似文献   

5.
Methodological improvements now allow routine analyses of highly degraded DNA samples as found in museum specimens. Using these methods could be useful in studying such groups as rodents of the genus Gerbillus for which i) the taxonomy is still highly debated, ii) collection of fresh specimens may prove difficult. Here we address precise taxonomic questions using a small portion of the cytochrome b gene obtained from 45 dry skin/skull museum samples (from 1913 to 1974) originating from two African and three Asian countries. The specimens were labelled Gerbillus gerbillus, Gerbillus andersoni, Gerbillus nanus, Gerbillus amoenus, Gerbillus perpallidus and Gerbillus pyramidum, and molecular results mostly confirmed these assignations. The close relationship between Gerbillus nanus (Asian origin) and Gerbillus amoenus (African origin) confirmed that they represent vicariant sibling species which differentiated in allopatry on either side of the Red Sea. In the closely related Gerbillus perpallidus and Gerbillus pyramidum, specimens considered as belonging to one Gerbillus pyramidum subspecies (Gerbillus pyramidum floweri) appeared closer to Gerbillus perpallidus suggesting that they (Gerbillus pyramidum floweri and Gerbillus perpallidus) may represent a unique species, distributed on both sides of the Nile River, for which the correct name should be Gerbillus floweri. Furthermore, the three other Gerbillus pyramidum subspecies grouped together with no apparent genetic structure suggesting that they may not yet represent genetically differentiated lineages. This study confirms the importance of using these methods on museum samples, which can open new perspectives in this particular group as well as in other groups of interest.  相似文献   

6.
Adipose tissue can store over 50% of whole-body cholesterol; however, the physiological role of adipose tissue in cholesterol metabolism and atherogenesis has not been directly assessed. Here, we examined lipoprotein metabolism and atherogenesis in a unique mouse model of severe lipodystrophy: the Seipin/ mice, and also in mice deficient in both low-density lipoprotein receptor (Ldlr) and Seipin: the Ldlr/ Seipin/ mice. Plasma cholesterol was moderately increased in the Seipin/ mice when fed an atherogenic diet. Strikingly, plasma cholesterol reached ~ 6000 mg/dl in the Seipin/ Ldlr/ mice on an atherogenic diet, as compared to ~ 1000 mg/dl in the Ldlr/ mice on the same diet. The Seipin/ Ldlr/ mice also developed spontaneous atherosclerosis on chow diet and severe atherosclerosis on an atherogenic diet. Rosiglitazone treatment significantly reduced the hypercholesterolemia of the Seipin/ Ldlr/ mice, and also alleviated the severity of atherosclerosis. Our results provide direct evidence, for the first time, that the adipose tissue plays a critical role in the clearance of plasma cholesterol. Our results also reveal a previously unappreciated strong link between adipose tissue and LDLR in plasma cholesterol metabolism.  相似文献   

7.
Labidocera churaumi sp. n. is described from Okinawa, southwestern Japan. The female of the new species differs from other congeners in genital compound somite with right postero-lateral and left antero-lateral processes. The male is distinguished from other congeners by the structure of the fifth leg. This new species is assigned to a newly proposed species group, the Labidocera madurae species group, within the Labidocera detruncata species complex. In this species complex five Indo-West Pacific species groups are recognized (cervi, detruncata, gangetica, madurae, and pavo) and defined on the basis of difference in sexual dimorphism.  相似文献   

8.
The results of long-term studies of mosquitoes in Belgorod Province are reported. The material was collected at 54 sites situated in 15 districts of the province. Different biotopes were investigated during the spring-autumn period. Larvae and adult mosquitoes were used for identification. A total of 27 mosquito species were found in the region examined. The following species were recorded for the first time: Ae. (Och.) communis. Ae. (Och.) diantaeus. Ae. (Och.) pulchritarsis. Ae. (Och.) sticticus, and Cx. (Bar.) modestus; and also the form Cx. (Cux.) pipiens pipiens biotype molestus. The frequency of occurrence of each species in different biotopes and different localities is given. The most widespread and common species in Belgorod Province include Ae. (Och.) cantans (Mg.), Ae. (Och.) cataphylla Dyar, Ae. (Fin.) geniculatus (Ol.), Ae. (Adm.) vexans (Mg.), Cx. (Cux.) pipiens, and Cx. (Cux.) pipiens pipiens biotype molestus.  相似文献   

9.
Diamond-Blackfan anemia (DBA), an inherited bone marrow failure syndrome characterized by anemia that usually presents before the first birthday or in early childhood, is associated with birth defects and an increased risk of cancer. Although anemia is the most prominent feature of DBA, the disease is also characterized by growth retardation and congenital malformations, in particular craniofacial, upper limb, heart, and urinary system defects that are present in ∼30%–50% of patients. DBA has been associated with mutations in seven ribosomal protein (RP) genes, RPS19, RPS24, RPS17, RPL35A, RPL5, RPL11, and RPS7, in about 43% of patients. To continue our large-scale screen of RP genes in a DBA population, we sequenced 35 ribosomal protein genes, RPL15, RPL24, RPL29, RPL32, RPL34, RPL9, RPL37, RPS14, RPS23, RPL10A, RPS10, RPS12, RPS18, RPL30, RPS20, RPL12, RPL7A, RPS6, RPL27A, RPLP2, RPS25, RPS3, RPL41, RPL6, RPLP0, RPS26, RPL21, RPL36AL, RPS29, RPL4, RPLP1, RPL13, RPS15A, RPS2, and RPL38, in our DBA patient cohort of 117 probands. We identified three distinct mutations of RPS10 in five probands and nine distinct mutations of RPS26 in 12 probands. Pre-rRNA analysis in lymphoblastoid cells from patients bearing mutations in RPS10 and RPS26 showed elevated levels of 18S-E pre-rRNA. This accumulation is consistent with the phenotype observed in HeLa cells after knockdown of RPS10 or RPS26 expression with siRNAs, which indicates that mutations in the RPS10 and RPS26 genes in DBA patients affect the function of the proteins in rRNA processing.  相似文献   

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12.
The present checklist includes data on the species composition, geographic distribution and feeding preferences of thrips species in Bulgaria. In total, 155 species in 48 genera are listed. Of these, 125 species belong to suborder Terebrantia and include 103 species of 33 genera in family Thripidae, 14 species of two genera in Aeolothripidae, seven species of two genera in Melanthripidae and one species in Fauriellidae. In suborder Tubulifera, 30 species of 10 genera in the single family Phlaeothripidae are listed. Of the 155 Bulgarian thrips species, 87.7% are phytophagous, 4.5% are obligate predators, 5.8% are mycophagous and 1.9% are with unknown feeding preferences. Fourteen pest species are listed for Bulgaria, of which Frankliniella occidentalis, Thrips tabaci and Haplothrips tritici are of economic importance. The list provides detailed information on the horizontal and vertical distribution of Thysanoptera in 5 regions and 45 subregions of Bulgaria. The present paper also includes an evaluation of the biodiversity of Thysanoptera and the extent to which each region of the country has been studied.  相似文献   

13.
We describe Lonchophylla inexpectata sp. n. from the Caatinga of Brazil. This new species can be distinguished from all known species of Lonchophylla that occur in Brazil by dental traits, cranial size, and fur colour. Specimens of Lonchophylla inexpectata have been misidentified as Lonchophylla mordax; but Lonchophylla inexpectata is a pale-venter species, similar in external appearance to Lonchophylla dekeyseri. We have found Lonchophylla inexpectata in the Caatinga of North-eastern Brazil; Lonchophylla mordax along the eastern border of the Caatinga and in the Atlantic Forest–Caatinga ecotone in North-eastern Brazil; and Lonchophylla dekeyseri in the Cerrado of Mid-western Brazil, in the Brazilian Cerrado–Caatinga ecotone, and as far west as the Cerrado of Bolivia.  相似文献   

14.
Many species in the families of Rosaceae, Solanaceae, and Scrophulariaceae exhibit gametophytic self-incompatibility, a phenomenon controlled by two polymorphic genes at the S-locus, style-S (S-RNase) and pollen-S (SFB). Sequences of both genes show high levels of diversity, characteristic of genes involved in recognition of self-incompatibility systems in plants. In this study, S 24 -RNase and SFB 24 alleles were cloned from Prunus armeniaca cv. Chuanzhihong (Chinese apricot). Sequence comparisons of deduced amino acid sequences revealed that the P. armeniaca S 24 -haplotype has different SFB alleles, but shares a single S-RNase allele with P. armeniaca S 4 -haplotype. Moreover, P. armeniaca S 24 -RNase haplotype has a single and three different alleles with S 1 -RNase of P. tenella (dwarf almond) and S 1 -RNase of P. mira (smooth pit peach), respectively. The functionalities of SFB 24 and SFB 4 have been evaluated by pollen tube growth and controlled field tests of P. tenella and P. mira. Genetic analysis of the two intercrosses showed that progenies segregated 1:1 into two S-genotype classes, which is consistent with the expected ratio for semi-compatibility. These findings imply that the allelic function of the S 24 -haplotype is identical to that of the S 4 -haplotype in a self-incompatibility reaction. Thus, these two Prunus S-haplotypes are in fact two neutral variants of the same S-haplotype. The evolution of the S-allele is also discussed in terms of both functions and differences between S 24 - and S 4 -haplotypes in Prunus.  相似文献   

15.
Third instar larvae of members of the Ceratitis FAR complex, including Ceratitis fasciventris (Bezzi), Ceratitis anonae Graham, and Ceratitis rosa Karsch are described and compared with those of Ceratitis capitata (Wiedemann). Diagnostic characters, such as presence vs. absence of a secondary tooth on the mandibles, previously used to separate Ceratitis capitata from Ceratitis rosa, are shown to vary in each species. Significant variation in diagnostic morphological characters among populations of Ceratitis rosa from east and south Africa is documented; however, the differences are not simply congruent with the R1 and R2 designations based on other studies. Quantitative measures of numerous morphological characters are consistently smaller in the larvae of Ceratitis fasciventris and distinguish them from other species of the FAR complex. Larvae of Ceratitis capitata can be distinguished from those of the FAR complex by characters such as absence of accessory plates of the oral ridges, the shape of the anterior spiracle, and the pattern of dorsal spinules. Previous studies indicated that absence of accessory lobes separate the genus Ceratitis from Bactrocera, but this is shown to be incorrect, as accessory lobes are in fact present in several species of Ceratitis.  相似文献   

16.
Chinese species in the genus Nycheuma Fennah, 1964a (Hemiptera: Fulgoromorpha: Delphacidae: Delphacinae: Delphacini) are revised to include three species: Nycheuma cognatum (Muir, 1917), Nycheuma dimorpha (Matsumura, 1910) and Nycheuma nilotica Linnavuori, 1973. Nycheuma coctum Yang, 1989 is placed in synonymy with Nycheuma nilotica Linnavuori, 1973. Nycheuma dimorpha (Matsumura, 1910) is newly recorded from China. The generic characteristics are redefined. The main morphological characters, male genitalia of 3 species are described or redescribed and illustrated. A key to Chinese species in the genus is provided.  相似文献   

17.
Monocots are one of the most diverse, successful and economically important clades of angiosperms. We attempt to analyse the complete plastid genome sequences of two lilies and their lengths were 152,793bp in Lilium longiflorum (Liliaceae) and 155,510bp in Alstroemeria aurea (Alstroemeriaceae). Phylogenetic analyses were performed for 28 taxa including major lineages of monocots using the sequences of 79 plastid genes for clarifying the phylogenetic relationship of the order Liliales. The sister relationship of Liliales and Asparagales-commelinids was improved with high resolution. Comparative analyses of inter-familial and inter-specific sequence variation were also carried out among three families of Liliaceae, Smilacaceae, and Alstroemeriaceae, and between two Lilium species of L . longflorum and L . superbum . Gene content and order were conserved in the order Liliales except infA loss in Smilax and Alstroemeria . IR boundaries were similar in IRa, however, IRb showed different extension patterns as JLB of Smilax and JSB in Alstroemeria . Ka/Ks ratio was high in matK among the pair-wise comparison of three families and the most variable genes were psaJ, ycf1, rpl32, rpl22, matK, and ccsA among the three families and rps15, rpoA, matK, and ndhF between Lilium.  相似文献   

18.
The Liolaemus nigroviridis group is a clade of highland lizards endemic to Chile. These species are distributed from northern to central Chile, and currently there are no cases of sympatric distribution. This study describes a new species, Liolaemus uniformis sp. n., from this group, and provides a detailed morphological characterization and mitochondrial phylogeny using cytochrome-b. Liolaemus uniformis was found in sympatry with Liolaemus nigroviridis but noticeably differed in size, scalation, and markedly in the color pattern, without sexual dichromatism. This new species has probably been confused with Liolaemus monticola and Liolaemus bellii, both of which do not belong to the nigroviridis group. The taxonomic issues of this group that remain uncertain are also discussed.  相似文献   

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20.
The elongatus-kriegi complex is one of the most diverse clades of the Liolaemus (sensu stricto) subgenus of lizards. There are currently 29 species recognized in this group distributed between Chile and Argentina. Based on molecular evidence, there seem to be five main clades nested within this complex: the elongatus, leopardinus, kriegi, petrophilus and punmahuida clades. Liolaemus buergeri and Liolaemus kriegi, both of the kriegi clade, were believed to inhabit the surroundings of the Laja Lagoon, in the Biobío Region of Chile. Moreover, this Chilean population of Liolaemus kriegi was recently recognized as an undescribed taxon called “Liolaemus sp. A” based on molecular phylogenetics. In this work, we studied these two populations of the Laja Lagoon and provided the morphological diagnosis to describe them as two new species: Liolaemus scorialis sp. n. and Liolaemus zabalai sp. n., previously considered Liolaemus buergeri and “Liolaemus kriegi/Liolaemus sp. A” respectively. Additionally, we identified another population of Liolaemus scorialis in the vicinity of La Mula Lagoon in the Araucanía Region of Chile. Liolaemus scorialis differs from almost all of the species of the elongatus-kriegi complex by its considerably smaller size. Nevertheless, without molecular data we cannot assign it to any particular subclade. Liolaemus zabalai belongs to the kriegi clade based on published molecular phylogenies. Finally, we provide some natural history data on both species and we document for the first time the presence of Liolaemus neuquensis in Chile from a museum specimen from La Mula Lagoon.  相似文献   

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