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1.
Six species/subspecies of Asian high-mountain voles, genus Alticola, were studied cytogenetically via conventional staining and C- and G-banding. The karyotypes are very similar. The standard karyotype, as in A. strelzovi strelzovi, consists of 56 chromosomes. These are split into 25 acrocentric pairs, one large subtelocentric pair, one small metacentric pair, a large acrocentric X chromosome, and a small Y chromosome, which varies in shape. Constitutive heterochromatin is almost entirely restricted to small centromeric regions. A small submetacentric pair of autosomes in both subspecies of A. semicanus and a medium-sized Y chromosome in A. argentatus severtzovi are of importance in systematics. The data suggest that A. barakshin, A. semicanus, and A. argentatus are separate species.  相似文献   

2.
The dorsal lateral geniculate bodies (dLGB) in Alticola stoliczkanus barakshin, the Gobi-Altai-Mountain vole, and in Alticola argentatus semicanus, the silver grey mountain vole, and investigated using the nissl- and the golgi method. The geniculo-cortico-relay neurons (GCR neurons) of both species have 5 primary dendrites (D1), a dendritic field of about 100 micron, about 17 free dendritic distal parts (FDE), 10 branching points (VZP) and a average of the perikaryon of 10 micron. All tufted neurons are small and topographically distinctly localised. The dLGB's volume of Alticola stoczkanus, barakshin is 0.16 mm3, the dLGB's volume of Alticola argentatus semicanus is 0.23 mm3.  相似文献   

3.
Abstract  Orosius argentatus shows extreme colour variation and is reputedly highly polyphagous, circumstances that both warrant confirmation that the taxon comprises only one species. Because the species transmits phytoplasma pathogens between plants, information on species status is relevant to epidemiological studies. Replicated field samples, taken in Mareeba, North Queensland, over 2 years indicated that O. argentatus is the most abundant leaf-hopper in stylo ( Stylosanthes scabra ) and is relatively host-specific on cultivated stylo, at least locally. A priori groupings of colour types were established for morphometric analyses of head, prothorax, tibia, wing and genitalia characters. No consistent morphological differences were detected across the colour types, and results from colour heritability trials, although limited, revealed that females could produce progeny that belong to multiple colour types. The results from this study suggest individuals that key out to the species O. argentatus, despite being polymorphic in colour, cannot be clearly separated on any morphological basis and therefore are likely to belong to a single, interbreeding population. The colour variation in adults is therefore a polymorphism.  相似文献   

4.
One hundred and eleven Lepidapedon elongatum-like worms from five gadiform fish species in the North Atlantic are compared using multivariate analyses of 22 metrical features. A principal component analysis followed by a discriminant analysis indicate multivariate morphological differences between worms in the different hosts. It is argued that the forms in the five host species, Gadus morhua, Onogadus argentatus, Trachyrhynchus trachyrhynchus, Coryphaenoides (Nematonurus) armatus and Lepidion eques, should be considered separate oioxenic species.  相似文献   

5.
郭鹏 《四川动物》2005,24(3):428-431
2004年以来,广义竹叶青蛇的系统学研究取得了较大的进展。本文对这近一年来的最新进展进行概括和报道。  相似文献   

6.
The complete mitochondrial genome sequence of the silver croaker, Argyrosomus argentatus, was obtained by using LA-PCR and sequencing. The mitogenome is 16485 bp in length, consists of 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a non-coding control region like those found in other vertebrates, with the gene order similar to that of typical teleosts. Most of the genes of A. argentatus were encoded on the H-strand, while the ND6 and eight tRNA (Gln, Ala, Asn, Cys, Tyr, Ser (UCN), Glu and Pro)) genes were encoded on the L-strand. The reading frames of two pairs of genes overlapped: ATPase8 and 6 and ND4L and ND4 by ten and seven nucleotides, respectively. The origin of L-strand replication in A. argentatus was in a cluster of five tRNA genes (WANCY) and was 46 nucleotides in length. The conserved motif (5'-GCGGG-3') was found at the base of the stem within the tRNA(Cys) gene. Within the control region, we identified all of the conserved motifs except for CSB-F.  相似文献   

7.
Abstract   The leafhoppers Orosius argentatus (Evans), Austroagallia torrida (Evans) and Batracomorphus angustatus (Osborn) were used in transmission tests to determine their vector status for the phytoplasma associated with Australian lucerne yellows (ALuY). Caged, seed-grown lucerne plants were monitored for foliar symptom expression after feeding by leafhoppers transferred from ALuY symptomatic lucerne plants. Twelve of 25 plants developed phytoplasma disease-like symptoms including stunting and yellowing. The most pronounced foliar symptoms were displayed by five plants that had been fed on by O. argentatus and four plants that had been fed on by A. torrida. One plant, fed on by O. argentatus , showed the distinctive root symptoms of ALuY . A phytoplasma was identified by electron microscopy in two plants fed on by O. argentatus and one by A. torrida. For each group of plants that had been fed on by a single leafhopper species, one plant was phytoplasma positive as determined by the polymerase chain reaction (PCR) using universal primers. The phytoplasma detected by PCR in the plant fed on by A. torrida was identified by restriction fragment length polymorphism (RFLP) analysis as the tomato big bud (TBB) phytoplasma. The PCR product from two plants fed on by B. angustatus and O. argentatus were too faint for RFLP analysis. PCR assays were conducted on DNA extracted from the head and thorax of each leafhopper species from transmission tests and from field-collected insects, but no phytoplasma DNA was detected. These findings suggest O. argentatus is a vector of the ALuY pathogen and A. torrida is a vector of the TBB phytoplasma.  相似文献   

8.
PIERRE YÉSOU 《Ibis》1991,133(3):256-263
An opportunity to study the validity of the species Larus cachinnans , considered by some authors as merely a group of races related to either L. fuscus or L. argentatus , is given by its sympatric breeding with these species. Both of these latter species have recently extended their breeding range southwards, while Mediterranean representatives of the cachinnans group have spread northwards, and the three forms now breed side by side over c. 350 km along the Atlantic coast of France, where their breeding biology was studied from 1983 to 1990. L. cachinnans is very territorial, some pairs holding territories almost all year round; argentatus pairs may defend territories from mid-winter; and the supposedly migratory fuse us are on their territories for only a short period before laying. L. cachinnans is an early breeder, laying from late March to early May, while fuscus lay from May into June, and argentatus has a protracted breeding season overlapping the other two. Interbreeding occasionally occurs; it can be productive in the case of fuscus x argentatus whereas fuscus x cachinnans attempts did not produce any young. No cachinnans x argentatus pair has been observed. This indicates strong reproductive isolation, evidence that L. cachinnans must be considered a good species.  相似文献   

9.
郭鹏  赵尔宓 《四川动物》2004,23(4):380-386
广义的竹叶青蛇属于Trimeresurus(sensu lato)包含有40多个物种,广泛分布在南亚和东南亚国家和地区。目前,该类群已经相继被划分为6个属:Trimeresurus(sensu stricto)、Tropidolaemus、Ovophis Protobothrops,Triceratolepidophis,Zhaoermia本文从形态、细胞以及分了系统学等方面对Trimeresurus(sensu lato)的分类和系统学研究进行综述。  相似文献   

10.
The pendulous, bitegmic, anatropous ovulr with dorsal raphe is suspended at the tip of a massive funicle. A group of nurellar cells with intensively staining cell walls, the hypostase sensu stricto , is present. The initially plate-like tanniniferous chalazal-nucellar tissue, with suberin and lignin impregnated cell walls represents a hypostase sensu lato . The mature seed-coat is formed by the raphe, extensive chalaza, adjacent, well-developed, cup-like hypostase sensu lato , remnants of the two integuments and a cuticular layer. The exalbuminous seed of Sclerocarya birrea suhsp. caffra (the Marula), is regarded to he a derived and phylogenetically advanced type. The undifferentiated seed-roat is very similar to that found in Lannea discolor which, like the marula, belongs to the tribe Spondieae. The similarities in the structure of the seed-coat and seed of the marula and L. discolor confirm their proposed close phylogenetir relationship.  相似文献   

11.
The interrelationships within theHeliantheae s. lato and the closely relatedEupatorieae are analyzed and discussed. The basis to this discussion is a cladistic analysis of 141 morphological characters (172 apomorphic states) scored for 97 genera. TheHeleniae s. lato, a subgroup of theHeliantheae s. lato, are paraphyletic, and a monophyletic group corresponding largely to theHeliantheae s. str. is recognized. TheEcliptinae sensuRobinson are polyphyletic. TheCoreopsidinae form an ingroup in theHeliantheae s. str. TheTageteae (Pectidinae) and theMadieae (Madiinae) are two separate branches within the helenioid assemblage of taxa.  相似文献   

12.
Oh DJ  Oh BS  Jung MM  Jung YH 《Mitochondrial DNA》2010,21(5):151-159
We cloned and sequenced the complete mitochondrial DNA (mtDNA) of three tilefishes (Branchiostegus albus, Branchiostegus argentatus, and Branchiostegus japonicus) to characterize and compare their mitochondrial genomes (mitogenomes). The mitogenomes of B. albus, B. argentatus, and B. japonicus were 16,532, 16,550, and 16,541 bp long, respectively, and all consisted of 37 genes (13 protein-coding genes, 2 ribosomal RNA, and 22 transfer RNA (tRNAs)), which are typical for vertebrate mtDNA. As in other bony fishes, most genes were encoded on the H-strand, except for the nad6 and eight tRNA genes that were encoded on the L-strand. Among the 13 protein-coding genes of all three tilefishes, 2 reading-frame overlaps were found on the same strand: atp8 and atp6 overlapped by 10 nucleotides, and nad4L and nad4 overlapped by 7 nucleotides. The identity of the nad4 gene between B. albus and B. argentatus was the lowest at 87%. Conversely, the identity of the nad6 gene between B. albus and B. japonicus was the highest at 99%. Most tRNA genes were similar in length among the three species, while the tRNA-Ser((AGY)) of B. japonicus was 9 bp longer than those of B. albus and B. argentatus. The control region of the mitogenome spanned 853, 862, and 856 bp in B. albus, B. argentatus, and B. japonicus, respectively. A maximum likelihood tree constructed using 11,035 sites contained five independent groups with bootstrap values of 100% in support of their divergence. All three tilefishes examined were clustered with the Pomacanthidae species in Group II.  相似文献   

13.
Relationships among the morphologically diverse members of Saxifragaceae sensu lato were inferred using 130 18S rDNA sequences. Phylogenetic analyses were conducted using representatives of all 17 subfamilies of Saxifragaceae sensu lato, as well as numerous additional taxa traditionally assigned to subclasses Magnoliidae, Caryophyllidae, Hamamelidae, Dilleniidae, Rosidae, and Asteridae. This analysis indicates that Saxifragaceae should be narrowly defined (Saxifragaceae sensu stricto) to consist of ~30 herbaceous genera. Furthermore, Saxifragaceae s. s. are part of a well-supported clade (referred to herein as Saxifragales) that also comprises lteoideae, Pterostemonoideae, Ribesioideae, Penthoroideae, and Tetracarpaeoideae, all traditional subfamilies of Saxifragaceae sensu lato, as well as Crassulaceae and Haloragaceae (both of subclass Rosidae). Paeoniaceae (Dilleniideae), and Hamamelidaceae, Cercidiphyllaceae, and Daphniphyllaceae (all of Hamamelidae). The remaining subfamilies of Saxifragaceae sensu lato fall outside this clade. Francoa (Francooideae) and Bauera (Baueroideae) are allied, respectively, with the rosid families Greyiaceae and Cunoniaceae. Brexia (Brexioideae), Parnassia (Parnassioideae), and Lepuropetolon (Lepuropetaloideae) appear in a clade with Celastraceae. Representatives of Phyllonomoideae, Eremosynoideae, Hydrangeoideae, Escallonioideae, Montinioideae, and Vahlioideae are related to taxa belonging to an expanded asterid clade (Asteridae sensu lato). The relationships suggested by analysis of 18S rDNA sequences are highly concordant with those suggested by analysis of rbcL sequences. Furthermore, these relationships are also supported in large part by other lines of evidence, including embryology. serology, and iridoid chemistry.  相似文献   

14.
From the revision of more than 1,250 serpulids, 15 species from the Grand Caribbean Region were identified and characterized. Thirteen species were collected along the shores of the Yucatan Peninsula and eight were found in other localities in the Gulf of Mexico, seven others are from Cuba and comments on type specimens of two species are also included. Three morphometric analyses were made to evaluate some characters. The first on Pomatostegus stellatus (Abildgaard), and related species and subspecies: P. brachysoma Schmarda, P. macrosoma Schmarda, P. s. fruticosa M?rch, P. s. pentapoma M?rch and P. s. tetrapoma M?rch, indicated that they are conspecific. Another one on Spirobranchus de Blainville species: S. dendropoma M?rch, S. giganteus (Pallas), S. polycerus (Schmarda) and S. polycerus augeneri ten Hove; indicated that S. giganteus differs from the other three taxa. The third analysis was made on Vermiliopsis annulata (Schmarda) sensu lato; it allowed the recognition of three different forms. Several incomplete specimens might belong to an undescribed genus. A key for identification of all the species recorded in the Grand Caribbean Region is also included.  相似文献   

15.
Lyme borreliosis (LB) group spirochetes, collectively known as Borrelia burgdorferi sensu lato, are distributed worldwide. Wild rodents are acknowledged as the most important reservoir hosts. Ixodes scapularis is the primary vector of B. burgdorferi sensu lato in the eastern United States, and in the southeastern United States, the larvae and nymphs mostly parasitize certain species of lizards. The primary aim of the present study was to determine whether wild lizards in the southeastern United States are naturally infected with Lyme borreliae. Blood samples obtained from lizards in Florida and South Carolina were tested for the presence of LB spirochetes primarily by using B. burgdorferi sensu lato-specific PCR assays that amplify portions of the flagellin (flaB), outer surface protein A (ospA), and 66-kDa protein (p66) genes. Attempts to isolate spirochetes from a small number of PCR-positive lizards failed. However, PCR amplification and sequence analysis of partial flaB, ospA, and p66 gene fragments confirmed numerous strains of B. burgdorferi sensu lato, including Borrelia andersonii, Borrelia bissettii, and B. burgdorferi sensu stricto, in blood from lizards from both states. B. burgdorferi sensu lato DNA was identified in 86 of 160 (54%) lizards representing nine species and six genera. The high infection prevalence and broad distribution of infection among different lizard species at different sites and at different times of the year suggest that LB spirochetes are established in lizards in the southeastern United States.  相似文献   

16.
A field survey was conducted to investigate the presence of Borrelia burgdorferi sensu lato (s.l.) in six counties of Taiwan. Spirochetes were successfully isolated from one rodent ear sample out of 485 rodent ears and 53 live, fed tick (Ixodes granulatus) samples. The spirochetes were confirmed to be B. burgdorferi s.l. by real-time PCR. In addition, 23 of 113 tick samples were tested positive for Borrelia DNA according to real-time PCR. The Borrelia isolate from the rodent and the 23 Borrelia DNA samples from the ticks were identified as B. valaisiana-related genospecies by phylogenetic analysis based on flagellin gene sequences. These findings suggest that the Borrelia valaisiana-related strains are maintained in a zoonotic cycle between tick vectors and reservoir hosts in Taiwan.  相似文献   

17.
The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.l., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly.  相似文献   

18.
Little attention has been given in scientific literature to how introduced species may act as a new host for native infectious agents and modify the epidemiology of a disease. In this study, we investigated whether an introduced species, the Siberian chipmunk (Tamias sibiricus barberi), was a potentially new reservoir host for Borrelia burgdorferi sensu lato, the causative agent of Lyme disease. First, we ascertained whether chipmunks were infected by all of the B. burgdorferi sensu lato genospecies associated with rodents and available in their source of infection, questing nymphs. Second, we determined whether the prevalence and diversity of B. burgdorferi sensu lato in chipmunks were similar to those of a native reservoir rodent, the bank vole (Myodes glareolus). Our research took place between 2006 and 2008 in a suburban French forest, where we trapped 335 chipmunks and 671 voles and collected 743 nymphs of ticks that were questing for hosts by dragging on the vegetation. We assayed for B. burgdorferi sensu lato with ear biopsy specimens taken from the rodents and in nymphs using PCR and restriction fragment length polymorphism (RFLP). Chipmunks were infected by the three Borrelia genospecies that were present in questing nymphs and that infect rodents (B. burgdorferi sensu stricto, B. afzelii, and B. garinii). In contrast, voles hosted only B. afzelii. Furthermore, chipmunks were more infected (35%) than voles (16%). These results may be explained by the higher exposure of chipmunks, because they harbor more ticks, or by their higher tolerance of other B. burgdorferi sensu lato genospecies than of B. afzelii. If chipmunks are competent reservoir hosts for B. burgdorferi sensu lato, they may spill back B. burgdorferi sensu lato to native communities and eventually may increase the risk of Lyme disease transmission to humans.  相似文献   

19.
M. P. Harris 《Ibis》1965,107(1):43-53
The food of L. argentatus on Skomer and Skokholm Islands (Wales) was studied by the analysis of stomach contents, pellets and direct observation. L. argentatus is mainly a scavenger and exists for the most part on fish-waste and garbage discarded by man. At Ncwborough Warren argentatus feeds more on arable land and on the shore than do the Skokholm and Skomer birds.
Although argentatus frequently eats limpets Patella spp., there is little competition for food between them and Oystercatchers Haematopus ostralegus because the two species eat different sized limpets.
A summary of previous studies into the food of argentatus is given.
L. marinus is mainly a predator feeding on the young of other gulls, sea-birds and Rabbits but it also eats carrion, offal and fish-waste when available and during the winter. The numbers of Manx Shearwaters Procellaria puffinus killed on Skokholm and Skomer are discussed.
L. fuscus obtains most of its food on the shore and on arable land. There appears to be little competition, at least in the areas studied, between .fuscus and argentatus for food.  相似文献   

20.
To evaluate the prevalence rate of tick-borne bacterial pathogens, unfed adult Ixodes ricinus ticks were collected from vegetation in 2001, 2003, and 2004 at 18 localities throughout Serbia. A total of 287 ticks were examined by PCR technique for the presence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, and Francisella tularensis. The highest prevalence rate was that for B. burgdorferi sensu lato (42.5%), followed by A. phagocytophilum (13.9%) and F. tularensis (3.8%). The presence of five B. burgdorferi sensu lato genospecies, namely, B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. lusitaniae, and B. valaisiana was identified by restriction fragment length polymorphism (RFLP) analysis. The most frequent B. burgdorferi sensu lato genospecies was B. lusitaniae, followed by B. burgdorferi sensu stricto. Co-infection by B. burgdorferi sensu stricto and B. lusitaniae was frequently observed. Co-infection by B. burgdorferi sensu lato and A. phagocytophilum and co-infection by B. burgdorferi sensu lato and F. tularensis appeared in 24 ticks. Sequencing of p44/msp2 paralogs of Serbian A. phagocytophilum showed that they were unique and distinct from those of A. phagocytophilum in US and UK. This is the first report of B. garinii, B. lusitaniae, B. valaisiana, as well as A. phagocytophilum and F. tularensis infected ticks in Serbia. These findings indicate a public health threat in Serbia of tick-borne diseases caused by B. burgdorferi sensu lato, A. phagocytophilum and F. tularensis.  相似文献   

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