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1.
《African Zoology》2013,48(2):269-276
A new species of hyperoliid frog, Heterixalus carbonei n.sp., is described from the Antsingy forest inwestern Madagascar. It is characterized by an advertisement call consisting of long and regular note series. The only other Heterixalus with a similar call structure, H. betsileo from higher altitudes in eastern Madagascar, has distinctly shorter notes. After recent discoveries of the occurrence of H. luteostriatus and H. tricolor in western Madagascar, the new species brings the number of Heterixalus known from western Madagascar to three.  相似文献   

2.
A total of 26 samples of Matsoni were collected in Georgia. From these samples 80 strains of lactic acid cocci and 173 strains of lactobacilli were isolated. The number of lactic acid bacteria varied between 105 and 1010 colony forming unit (CFU)/mL. All the isolated lactic acid bacteria were thermophilic bacteria that could grow at 45°C. The predominant lactic acid bacteria were Streptococcus thermophilus and Lactobacillus delbrueckii spp. bulgaricus in 25 samples of Matsoni, while Lactobacillus helveticus was also a predominant species, together with the two previous species in one sample of Matsoni. We showed there was diversity in both S. thermophilus and L. delbrueckii spp. bulgaricus at the strain level by randomly amplified polymorphic DNA analysis.  相似文献   

3.
This study documents the fauna associated with two common comatulid crinoid species, Comanthus wahlbergi and Tropiometra carinata, in False Bay, South Africa, and describes the patterns of infestation of obligate associate species. A total of 11 invertebrate species was found associated with one or both crinoids. Of these, three were considered obligate: the myzostomidans, Myzostoma fuscomaculatum and Myzostoma n.sp., and the shrimp, Hippolyte catagrapha, all of which only occurred on T. carinata. Both frequency and density of infestation were higher for the two myzostomes than for the shrimp. The majority of crinoids infested with myzostomes hosted two or more individuals, while H. catagrapha usually occurred singly. A total of 67.5% of all T. carinata collected were infested by symbionts. Of these 45% hosted only one species, 17% hosted two species and 5.8% hosted all three. Most M. fuscomaculatum (85.2%) and H. catagrapha (82.1%) matched their hosts’ colouring, while Myzostoma n. sp. were all yellowish incolour. Infestation by Myzostoma n. sp. increased in both frequency and density with depth. All three obligate symbiont species are new to science, illustrating the biodiversity that can still be uncovered by investigating new niches.  相似文献   

4.
Four species of stichopodid holothurians, namely the Indo-West Pacific Stichopus chtoronotus Brandt, S. variegatus Semper, Thefenota anax H.L. Clark and the endemic Neostichopus grammatus (H.L. Clark) occur in the southern African shallow waters (south of 20°S latitude). Besides T. anax, which is not present in the material studied, notes are provided on the remaining three species, of which S. variegatus is here recorded from this region for the first time. The changes with age in the composition of the body wall spicules of N. grammatus are described and it is indicated that the characteristic dumb-bell-shaped deposits of the dorsal papillae, consistent in both juveniles and adults, offer a reliable and easily accessible morphological character in preserved specimens. A key to all four species is provided and their geographic distributions are mapped.  相似文献   

5.
The previously unknown life-cycles of Haemonchus bedfordi, Impalala tuberculata and Longistrongylus sabie parasitic in impala, are recorded. Observations on the morphology of the developmental stages and their habitat of these three nematode species are described. The similarities and differences to closely related species or subspecies are discussed.The morphology of the developmental stages of Haemonchus bedfordi are compared to the Haemonchus spp., H. contortus and H. placei.  相似文献   

6.
Helicobacter-like organisms are frequently observed in the stomach of dogs but the relationship between these microorganisms and gastric pathology has not been clearly established. Different species of helicobacters are known to be present in the canine stomach but their specific prevalence in naturally infected dogs is unknown. The aims of this study were to isolate and characterize helicobacters in canine gastric biopsies, to compare the commonly used tests for the identification of Helicobacter spp. and to determine the occurrence of these species in dogs. Twenty-three out of 25 dogs (92%) were positive for Helicobacter-like organisms in cytological screening. Culture was successful from biopsies of 5/25 dogs. The isolates were analyzed by electron microscopy, biochemical and physiological tests, whole protein analysis and 16S rDNA sequencing. Helicobacter felis was identified in four samples and Helicobacter bizzozeronii in one sample. Only the whole protein analysis in combination with electron microscopy was able to clearly discriminate the two species. Compared to the high prevalence of Helicobacter-like organisms, the occurrence of H. felis and H. bizzozeronii, was low (17 and 4%, respectively). No Flexispira rappini-like organisms or H. salomonis were detected. Electron microscopy revealed that H. bizzozeronii-like microorganisms were present in three additional biopsies where we were unable to culture any Helicobacter-like organisms. These observations indicate that in the stomach of dogs not all helicobacters are culturable. The unculturable bacteria appeared to be the prevalent ones and may represent different spiral organisms. The presence of distinct helicobacters with different characteristics can reflect different roles in the pathogenesis of canine gastric disease.  相似文献   

7.
Hard ticks (Acari: Ixodidae) were collected from the vegetation at monthly intervals in 2008 on six places of three different biotopes in Hungary. Except for Haemaphysalis concinna and H. punctata, predominance of females was observed in the questing population. From among the species with biphasic activity period, metastriate ticks (Dermacentor spp. and H. inermis) had higher prevalence of host-seeking males in the autumn than in the spring, as opposed to prostriate Ixodes ricinus. In comparison with the permanently mild weather experienced at the beginning of 2007, sharply rising temperatures during consecutive winter days in January and February of 2008 appeared to be more efficient in triggering a 1–2 month earlier spring peak activity of hard ticks, except for I. ricinus. Regarding seasonality, D. marginatus was most numerous in February and March, whereas D. reticulatus in September and October; H. punctata showed peak activity in March–April, H. concinna in May, and H. inermis in November–December. Within these genera such a temporal difference (allochrony) between seasonal peak activities of sympatric species under continental climate is described for the first time.  相似文献   

8.
Abstract

AIM: To describe the seasonal pattern of development of third-stage infective larvae (L3) from eggs of Teladorsagia (=Ostertagia) circumcincta, Trichostrongylus colubriformis and Haemonchus contortus on pasture in the North Island of New Zealand.

METHODS: Sheep faeces containing known numbers of eggs of all three nematode species were deposited on, or buried in, pasture plots at three sites, viz coastal Manawatu, Upper Hutt Valley, and East Cape hill country. Development was measured by recovering L3 from faeces, herbage and soil 28–31 days after deposition on 13–18 occasions, between January 2005 and July 2006. Analysis of the number of larvae recovered used a mixed model including number of eggs deposited, weight of faeces recovered (an assumed indicator of earthworm activity), site, contamination date, and position of deposited faeces, i.e. on the surface or buried.

RESULTS: There was a significant effect of contamination date on development of all three species, with maximum numbers ofL3 developing between late spring (November) and early autumn (March), and minimum numbers in June and July. There were large differences between species, with H. contortus exhibiting a long period (April to October) where development was close to zero, whereas T. circumcincta developed to some extent all year round. Development of T. colubriformis was intermediate between the other two species.

Burying faeces containing nematode eggs increased the number of L3 recovered compared with surface deposition (p≤0.001), although there were a small number of exceptions involving only T. colubriformis. The weight of faeces recovered at harvest, which was assumed to be an indication of earthworm activity, was correlated with the number of L3 recovered for all species (p<0.001). In a separate analysis, earthworms were assumed tohave been active if <5 g faeces remained at harvest. Where this occurred, the number of L3 of T. colubriformis and T.circumcincta recovered was reduced by 56% and 58%, respectively (p<0.001).

CONCLUSIONS: A marked seasonal pattern of development was observed for all three species, with the most larvae developing in spring-early autumn and the least in winter. This seasonal pattern was most pronounced in H. contortus and least obvious in T. circumcincta. Burying faeces containing eggs generally resulted in more L3 being recovered, whilst the apparent activity of earthworms resulted in fewer larvae being recovered.  相似文献   

9.
A full history of four nominal species of southern African dendrochirotid holothurians, namely Cucumaria jägeri Lampert, Semperia (= Cucumaria) sykion Lamped, C. insolens Theél and C. sinorbis Cherbonnier, is given and the confusion in their taxonomic status discussed. Morphological differences and habitat selection indicate that the latter three are valid sister species. C. jägeri is relegated to the synonymy of C. sykion, a well-established name which it threatens. Since none of the three species is referable to the genus in which it is currently classified, a new genus Pseudocnella is erected to accommodate them. It is suggested that the Mediterranean Ocnus syracusanus (Grube) be also classified in the new genus. A key to the three southern African species is given, their synonymy detailed, additional notes provided, and the geographic distributions mapped. Although P. sykion and P. sinorbis have an identical geographical range it is demonstrated that the two species are ecologically isolated and thus prevented from any interspecific competition. P. insolens is sympatric with P. sinorbis over a wide area, often occupying the same habitat in a single locality. However, morphological and other evidence points to subtle niche differences between them. A provisional cladogram is proposed to show the possible relationships of the four species included in the new genus.  相似文献   

10.
Over two consecutive years, weekly examinations for the presence of nematodes were conducted on 185 stomachs from donkeys originating mainly from the Rabat, Casablanca and Settat regions of Morocco. All the animals, except one, were infected by at least one of four helminth species.Trichostrongylus axei was found in 93.5%,Habronema muscae in 89.7%,H. majus in 85.4% andDraschia megastoma in 1.1% of donkeys. Most animals were infected by two (23.8%) or three (71.9%) species. High burdens ofT. axei were observed in the winter of both years and in the mid-summer of the second year. Peak burdens ofHabronema were found at various times throughout both years. There were more adultH. majus thanH. muscae. The periods of peak levels of infection by these parasites were related to environmental conditions suitable for the development and survival of infective larvae ofT. axei and for the build-up of muscid fly vectors ofHabronema andDraschia spp.  相似文献   

11.
Horus is an olpiid pseudoscorpion of which nine species have been described from southern Africa; a tenth, debatable species was described from the Ivory Coast. The two most widely distributed species are H. granulatus and H. obscurus, the former occurring especially in the west and the other in the east, but their distributions overlap; in two instances they have been recorded from the same site. All species have a preference for rock outcrops, which are largely disjunct, and their regular prey comprises small ant species. Fieldwork over a period of 15 years indicated a very low dispersal rate; therefore one would expect localized ‘island’ populations rather than widely dispersed species. This means that the current species delimitations which lump geographically widespread populations may be incorrect. Mitochondrial DNA of specimens from each of 20 different localities across South Africa were analysed to test the hypothesis. Five of these localities did not yield results, but 14 yielded DNA from specimens which proved to belong to Horus and a fifteenth turned out to be a misidentified pseudoscorpion unrelated to Horus. The results were unequivocal: populations from each locality or group of closely-spaced localities were genetically distinct from any other one tested, and the greater the distance between localities, the greater the genetic differences (i.e. significant isolation by distance). This means that the current species delimitations for Horus are incorrect. It will require detailed micro-anatomical study to identify new characteristics on which species delimitations can be based in future.  相似文献   

12.
13.
During a survey of freshwater nematodes in South Africa, five species of Monhystera Bastian, 1865, were encountered. The five species, three of which are new to science, are described and figured, viz. Monhystera taaiboschiensis n.sp., M. magnacephala n.sp., M. gabaza n.sp., M. filiformis Bastian, 1865 and M. somereni Allgen, 1952.  相似文献   

14.
Culicoides biting midges (Diptera: Ceratopogonidae) are vectors of important diseases affecting wild and domestic animals. During the last decade they have played a major role in the epidemiology of the largest bluetongue epizootic ever recorded in Europe, the disease is transmitted between hosts almost exclusively by bites of Culicoides midges and affects both domestic and wild ruminants however severe disease usually occurs in certain breeds of sheep and some species of deer. An accurate vector identification is of major importance in arthropod borne diseases surveillance, as great differences in vectorial capacity are found even between close species. Unfortunately, specialized taxonomic knowledge of Culicoides identification is rarely available in routine surveillance, mainly based on wing morphology. Recently, some European species of Culicoides belonging to the subgenus Avaritia Fox, 1955 and Culicoides Latreille, 1809 have been described as new bluetongue virus vectors.In the present study, by using a fragment of the barcode region (COI gene) we report the presence of up to 11 species within the subgenus Culicoides in Catalonia (NE Spain), a region recently affected by a bluetongue epizootic. The molecular analysis revealed new non-described cryptic species which were grouped in three complexes of morphologically similar species, two in the Pulicaris complex resembling Culicoides pulicaris, two in the Fagineus complex resembling Culicoides fagineus and three in the Newsteadi complex resembling Culicoides newsteadi. The phylogenetic relationships among them showed that cryptic species detected in both Pulicaris and Fagineus complexes were closely related, whereas those in the Newsteadi complex were more distant. Accurate analysis of all species using morphological and molecular approaches resulted in the detection of diagnostic metric traits for cryptic species and the design of several new species-specific single and multiplex PCR assays to identify unambiguously all the species, most of them still lacking a specific molecular diagnosis.  相似文献   

15.
A new gekkonid species, Afroedura hawequensis, is described from the south-western Cape (South Africa). The three species groups recognized in the genus are discussed.  相似文献   

16.
A new dendrochirotid holothuroid, Neocucumis kilbumi, is described from waters 50 meters deep, off the southern coast of KwaZulu-Natal, South Africa. It appears quite close to N. watasei (Ohshima) and N. sordidatus (Sluiter), both from the West Pacific and to N. atlanticus (Ludwig & Heding) from the Atlantic Ocean and the Mediterranean Sea. It differs from the former in the nature of the calcareous ring and the disc and the spire of the body wall tables, from N. sordidatus in the completeness of its deposits and the number of polian vesicles and from N. atlanticus in the presence of handles to the quadrilocular table discs. The new species increases to ten the number of species now classified in the genus Neocucumis. A key to all the species is included.  相似文献   

17.
Abstract

Morphological studies were carried out on adult postmetamorphic females of three native South American genera of Lernaeidae (Crustacea: Copepoda: Cyclopoida) and these were compared with the imported species Lernaea cyprinacea. Two of the native species represent new genera, which are described as Amazolernaea sannerae gen. et sp. nov. and Bedsylernaea collaris gen. et sp. nov. The third native species had already been described as Perulernaea gamitanae Thatcher and Paredes, 1985. Amazolernaea sannerae from the cichlids Cichla monoculus and speckled pavon C. temensis was characterized as having four similar petal-like anchors, a long slender neck, thoracopods 1 and 2 close together, and a genital pore located equatorially in the well-developed hindbody. Bedsylernaea collaris differs from all known lernaeids in having a large inflated head region with one bulbous anchor on either side, a slender neck, a stout hindbody with a large pregenital prominence, a genital pore that is anterior to the midpoint on the hindbody, and collar-like extensions on the anterior extremity of the hindbody. Perulernaea gamitanae has two large and two small unbranched anchors, a long neck with prominent glands, and an elongate hindbody with a genital pore that is posterior to the midpoint. In contrast, all valid species of Lernaea have four frequently branching anchors, a neck region and hindbody that are not well defined, a short abdomen, and a genital pore at or near the posterior extremity.  相似文献   

18.
《African Zoology》2013,48(2):298-308
The distribution of the scorpion genus Buthus Leach, 1815 includes southwestern Europe, North and Central Africa and extends east towards the Arabian Peninsula. Phylogenetic relationships within the genus are complex and remain partially unresolved despite several previous assessments. A set of three mitochondrial markers, 12s, 16s and CO1, revealed the presence of five well-supported clades: three clades endemic to Morocco, one clade distributed across the Maghreb region and southwestern Europe and one endemic to Tunisia and Algeria. Morocco presents high levels of endemism and appears to be the centre of diversity for the genus. Further differentiation was found within the clade distributed in Tunisia and Algeria, with the discovery of new phylogenetic patterns. In addition, a phylogeny combining all published CO1 data for the genus emphasized the ongoing complex situation regarding the genus’ taxonomy. Highly similar sequences were attributed to different species by different authors throughout the tree, and no differentiated monophyletic species could be resolved. This lack of congruence between morphologically defined species and genetic lineages is a major hindrance in the study of the highly complex genus Buthus.  相似文献   

19.
《African Zoology》2013,48(3):107-111
Enteromius mattozi Guimaraes, 1884, a popular eating fish among local people, were examined for monogenean parasites as part of a larger study to ascertain the feasibility of establishing aquaculture production in Limpopo, South Africa. In this study a new monogenean parasite of the genus Dactylogyrus was collected from the gills of E. mattozi, and described. It differs from known species of this group in the shape, size and structure of the heavily sclerotized vaginal prop. The proximal end of the vaginal prop has three layers similar to stacked funnels of decreasing sizes leading into a tube. The male copulatory organ is also much larger and robust than those of related species. The name Dactylogyrus mattozii is proposed for this new species.  相似文献   

20.
Xiphinema stocken 'n. sp. is described from Botswana The new species is characterized by an exceptionally long and conspicuous peg on the tail, and seems to be most closely related to X. mammatum Siddiqi, 1979, from which it can be distinguished by the a ratio, odontostyle and total stylet length, spicule length, the shape of the lip region and tail peg and the presence of a pseudo-z differentiation in X. stocken.  相似文献   

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