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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.
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   

4.
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   

5.
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   

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.
Sixteen species of Cerambycidae are newly recorded for New Brunswick, Canada; Arhopalus obsoletus (Randall), Atimia confusa confusa (Say), Callidium frigidum Casey, Phymatodes amoenus (Say), Phymatodes testaceus (Linnaeus), Neoclytus mucronatus mucronatus (Fabricius), Xylotrechus aceris Fisher, Xylotrechus sagittatus sagittatus (Germar), Tylonotus bimaculatus Haldeman, Lepturges angulatus (LeConte), Lepturges symmetricus (Haldeman), Urgleptes querci (Fitch), Oplosia nubila (LeConte), Eupogonius subarmatus (LeConte), Monochamus carolinensis (Olivier), and Pogonocherus parvulus LeConte. Urgleptes signatus (LeConte) and Urgleptes querci are newly recorded from Nova Scotia. All but two specimens were collected in 12-funnel Lindgren traps. Xylotrechus aceris, Tylonotus bimaculatus, Lepturges angulatus, Lepturges symmetricus, Urgleptes signatus (NS), and Pogonocherus parvulus were detected exclusively in traps deployed in the forest canopy, and most individuals of Oplosia nubila and Monochamus carolinensis were captured in canopy traps. Arhopalus obsoletus, Atimia confusa confusa, Callidium frigidum, Phymatodes testaceus, and Xylotrechus sagittatus sagittatus were captured almost exclusively in traps near (1 m above) the forest floor. These results highlight the importance of sampling both the understory and upper canopy when using traps for surveying diversity of Cerambycidae.  相似文献   

8.
Juan J. Morrone 《ZooKeys》2013,(273):15-71
The phylogenetic relationships of the genera of Listroderini LeConte, 1876 are analyzed based on 58 morphological characters. The genera are grouped in four clades, which are given subtribal status: Macrostyphlina new subtribe (Adioristidius, Amathynetoides, Andesianellus, Macrostyphlus, Nacodius and Puranius), Palaechthina Brinck, 1948 (Anorthorhinus, Gunodes, Haversiella, Inaccodes, Listronotus, Neopachytychius, Palaechthus, Palaechtodes, Steriphus and Tristanodes), Falklandiina new subtribe (Falklandiellus, Falklandiopsis, Falklandius, Gromilus, Lanteriella, Liparogetus, Nestrius and Telurus), and Listroderina (Acroriellus, Acrorius, Acrostomus, Antarctobius, Germainiellus, Hyperoides, Lamiarhinus, Listroderes, Methypora, Philippius, Rupanius and Trachodema). The subtribes are characterized and keys to identify them and their genera are provided. Listroderini have four main biogeographical patterns: Andean (Macrostyphlina), Andean-New Zealand (Falklandiina), Andean-Neotropical-Australian (Listroderina) and Andean-Neotropical-Australian-New Zealand-Nearctic-Tristan da Cunha-Gough islands (Palaechthina). Geographical paralogy, particularly evident in the Subantarctic subregion of the Andean region, suggests that Listroderini are an ancient Gondwanic group, in which several extinction events might have obscured relationships among the areas.  相似文献   

9.
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   

10.
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   

11.
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   

12.
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   

13.
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   

14.
Coexistence of closely related species may be promoted by niche differentiation or result from interspecific trade-offs in life history and ecological traits that influence relative fitness differences and contribute to competitive inequalities. Although insufficient to prove coexistence, trait comparisons provide a first step to identify functional differences between co-occurring congeneric species in relation to mechanisms of coexistence. Here, a comparative review on life history and ecological traits is presented for two pairs of co-occurring species of spiny lobsters in the genus Panulirus: Panulirus gracilis and Panulirus inflatus from the Eastern Central Pacific region, and Panulirus argus and Panulirus guttatus from the Caribbean region. Panulirus gracilis and Panulirus inflatus have similar larval, postlarval, and adult sizes and a similar diet, but differ in degree of habitat specialization, fecundity, and growth rate. However, little is known on behavioral traits of these two species that may influence their competitive abilities and susceptibility to predators. The more abundant information on Panulirus argus and Panulirus guttatus shows that these two species differ more broadly in degree of habitat specialization, larval, postlarval and adult sizes, diet, fecundity, growth rate, degree of sociality, defense mechanisms, susceptibility to predators, and chemical ecology, suggesting a greater degree of niche differentiation between Panulirus argus and Panulirus guttatus than between Panulirus gracilis and Panulirus inflatus. Whether the substantial niche differentiation and apparent interspecific trade-offs between Panulirus argus and Panulirus guttatus relative to Panulirus gracilis and Panulirus inflatus reflect an earlier divergence of the former pair of species in the evolution of the genus constitutes an intriguing hypothesis. However, whether or not post-divergence evolution of each species pair occurred in sympatry remains uncertain.  相似文献   

15.
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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Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909) were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and Gudeodiscus messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and Plectopylis fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n.) on the basis of the morphology of the reproductive anatomy and the radula. The Chinese Gudeodiscus phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of Gudeodiscus phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.  相似文献   

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