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1.
Genetic relations between four European mice species of the genus Apodemus (Apodemus sylvaticus, A. flavicollis, A. microps and A. falzfeini) and five Transcaucasian ones (A. mystacinus, A. microps, and the forms No 2, 3p, 3f) were studied for 37 biochemical loci. Close genetic relations were demonstrated between the mice of subgenus Sylvaemus and A. mystacinus. A. microps and A. falzfeini from the Caucasus were shown conspecific to these species from the Ukraine and the presence of the two new different species--the form No 2 and 3p in the Caucasus was established.  相似文献   

2.
The use of scale inspection as a means of age-determination in Pomatoschistus microps and Pomatoschistus minutus in the Tagus estuary is confirmed, but annulus formation pattern is different from that described for P. microps in the area of the British Isles (Miller, 1975). In Britain, two annuli are laid down on the scales each year, but in the Tagus, only one annulus is formed. One possible reason for this difference is the fact that in the Tagus the peak breeding season and the lowest water temperatures coincide. Therefore, the two causes of annulus formation coexist at the same time of year.
Population structure in both species is dominated by the 0-group, which appears earlier (April/May) than reported for other areas. Maximum age seems not to exceed 26 months in P. microps and 32 months in P. minutus .  相似文献   

3.
Gyrodactylus rugiensis was originally described as a parasite occurring on the marine gobies Pomatoschistus minutus and Pomatoschistus microps. In our preliminary survey this species was also frequently found on Pomatoschistus pictus and Pomatoschistus lozanoi. Subsequent molecular analysis of the internal transcribed spacers rDNA region revealed that this parasite actually represents a complex of two apparently cryptic species, one restricted to P. microps and the other shared by P. minutus, P. lozanoi and P. pictus. Morphometric analyses were conducted on 17 features of the opisthaptoral hard parts of specimens collected from all four host species. Standard discriminant analysis showed a clear separation of both genotypes by significant differences in marginal hook and ventral bar features. Statistical classifiers (linear discriminant analysis and nearest neighbours) resulted in an estimated misclassification rate of 4.7 and 3.1%, respectively. Based on molecular, morphological and statistical analyses a new species, Gyrodactylus rugiensoides is described. This species seems to display a lower host-specificity than generally observed for Gyrodactylus species as it infects three sympatric host species.However, seasonal and host-dependent morphometric variation is shown for G. rugiensoides collected on P. pictus. Host-switching and gene flow might be important factors preventing speciation on closely related and sympatric host species. The presence of host associated species complexes in this Gyrodactylus-Pomatoschistus system is also confirmed by the presence of two host-dependent genotypes within G. micropsi found on P. minutus and P. lozanoi, and P. microps, respectively. By comparing host and parasite phylogeny, phylogenetic and ecological factors influencing host-specificity are discussed.  相似文献   

4.
A case of caecum nematodiasis is described in a guinea fowl (Numida melagris) from the Municipal Zoo, Presidencia Roque Saenz Pe?a (Chaco) Argentina. Nematodes obtained from the caecum were observed in optic microscopy. According to their morphometric characteristics and location in the definitive host, were identified as belonging to the family Heterakidae, species Heterakis gallinarum, (Schrank, 1788) Maden, 1949.  相似文献   

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SYNOPSIS The oocysts of 2 new species of Eimeria are described from heteromyid rodents. The subspherical to ellipsoidal cocysts of Eimeria reedi from Perognathus formosus averaged 22.6 by 20.8 μ. An ellipsoidal polar granule was present. The oocyst residuum was a single globule about 8 μ in diameter. The ovoid sporocysts averaged 10.9 by 7.7 μ and had a residuum of 6-12 granules. A Stieda body and substiedal body were present in the sporocysts. Eimeria chobotari oocysts, from Dipodomys merriami and D. microps , were ellipsoidal to ovoid and averaged 47.7 by 35.2 μ. No polar granule was seen. The large oocyst residuum consisted of several granules of various sizes. The ovoid sporocysts averaged 15.8 by 11.3 μ and had a residuum of many small granules. A Stieda body and substiedal body were present in the sporocysts.  相似文献   

8.
Canistropsis microps (Bromeliaceae: Bromelioideae) is an endemic species of Atlantic rain forest areas in Rio de Janeiro State, which are very abundant in not very disturbed forests in Ilha Grande, on the southern coast of the State. In this study, we analyzed the vertical and horizontal distribution patterns of the species in an area of rain forest with little evidence of disturbance at Vila Dois Rios, Ilha Grande, relating the patterns to sunlight in the microhabitat. We also identified the types of substrate used by the species and the rate of asexual reproduction. Canistropsis microps had high densities (estimated at 84,425 rosettes/ha), and has an aggregated distribution (Id = 2.86). About 80% of the rosettes were generated by clonal growth, whereas less than 20% were produced from seedlings. Most of the rosettes were found on straight tree trunks (DBH > 50 cm). There was a significant inverse correlation between the incidence of sunlight in the habitat and the abundance of individuals. Rosettes were found up to a maximum height of 9.5 m, but most occured between 1.5 and 5.5 m, where light varied from 25 to 50 micromol x s(-1) x m(-2). We conclude that vertical and horizontal distribution patterns in C. microps may be partially explained by the occurrence of appropriate substrate, an intensity of sunlight favorable to the development of the species and to a high rate of vegetative reproduction.  相似文献   

9.
对5种隙蛛亚科蜘蛛进行了重新描述:梯板隙蛛Coelotes microps Schenkel,1963;回弯隙蛛Coelotes palinitropus Zhu & Wang,1994;螺形龙角蛛Draconarius gyriniformis(Wang&Zbu,1991);三分龙角蛛Draconarius triatus(Zhu&Wang,1994),comb.nov.和西藏龙角蛛Draconarius tibetensis Wang,2003。回弯隙蛛、西藏龙角蛛两种蜘蛛的雌性及梯板隙蛛、螺形龙角蛛、三分龙角蛛三种蜘蛛的雄性均系首次报道。三分龙角蛛是从隙蛛属Coelotes移来的新组合。  相似文献   

10.
A histochemical study of the distribution of alkaline phosphatase in the skin of the Common goby, Pomatoschistus microps , showed that the enzyme is present in the dermis, not in the epithelium, and is more pronounced around the growing edge of the scale and below the fibrillary plate. The intensity of the enzyme reaction is higher in regenerated scales. In conjunction with the phenology of P. microps , a method was adopted to measure the enzyme activity in the skin, including scales, for successive months over a period of two years. Enzyme activity displayed seasonal fluctuations which were closely related to both body and scale growth. Enzyme activity also reflected other phenological cycles during the life-span of P. microps .  相似文献   

11.
A new oxyurid nematode Syphacia (Syphacia) longaecauda n. sp. is described from the caecum and colon of the hydromyine rodents Melomys monktoni (type host) and M. rubex from Papua New Guinea and Irian Jaya, Indonesia. Syphacia longaecauda has an oval, laterally extended, relatively large cephalic plateau and can be distinguished from other species of Syphacia with similar characters by, amongst other features, tail length. The significance of the distribution of S. longaecauda, apparently restricted to New Guinea, is discussed.  相似文献   

12.
The diversity of bacteria present in the caecum of the rabbit was investigated. Partial bacterial 16S rRNA genes from a digested sample collected from the caecum of an adult rabbit were amplified by PCR. Sequence analysis of the amplified fragments indicated highest similarity was to bacterial sequences previously described from other gut environments. However, only one sequence showed significant identity (97% threshold) to any previously described bacterial 16S rRNA genes. Furthermore, most of the sequences clustered together in groups lacking representatives from sequences already described, suggesting that the rabbit caecal flora contains organisms not previously described.  相似文献   

13.
The Gyrodactylus spp. fauna on species of gobies, Pomatoschistus, Gobiusculus, and Knipowitschia (Gobiidae: Teleostei), from the western Mediterranean and Adriatic seas is strikingly similar to that found in the Baltic Sea and eastern Atlantic Ocean, both in morphology and in internal transcribed spacer (ITS) rRNA. The fauna consisted of Gyrodactylus branchialis, G. ostendicus, G. gondae, G. rugiensis, G. rugiensoides, and G. arcuatus. No new species have been found. A morphometric comparison between G. branchialis from the Mediterranean and Adriatic seas and its type locality in Ostend (Belgium) showed significant differences in ventral bar and marginal hook features. The morphometric variation was lower in G. rugiensis, whereas no significant differences were found in G. ostendicus. Gyrodactylus branchialis and G. ostendicus collected on P. microps were slightly different in the ITS rDNA (-0.6%) compared with specimens on the closely related P. marmoratus, probably reflecting ongoing speciation. A hybrid zone was identified in the Vaccarès lagoon complex (France) where both host species are sympatric. There was no clear geographic or host-related pattern in the variation found in the ITS2 rDNA in G. arcuatus sampled from P. microps, G. flavescens, Pungitius pungitius, K. panizzae, and its original host Gasterosteus aculeatus (2 polymorphic sites). Of all studied species, only G. arcuatus, G. rugiensis, and G. rugiensoides showed minor intraspecific variation in the ITS rDNA. Hence, the physical separation by a shoreline of more than 10,000 km is hardly reflected in the parasite ITS rDNA.  相似文献   

14.
Hysterothylacium pseudotumbili n.sp. from the stomach and body cavity of marine fishes. Chrorinemus tol Couvier. Saurida undosquamis (Richardson), Lutianus russelli (Bleeker), Rastrilliger kanagurta (Cuvier) and Saurida pseudotumbili Dutt and Vidyasagar collected from Visakhapatnam (Bay of Bengal) is described and figured. A detailed examination has allowed us to erect a new species of Hysterothylacium to accommodate the worm. It shows remarkable differences from other known species of Hysterothylacium in respect of body measurements, the papillae on the lips arrangement, location of nerve ring and excretory pore, long intestinal caecum, position of vulva, number and arrangement of caudal papillae and size of the spicules. The new species is designated as Hysterothylacium pseudotumbili. Saurida pseudotumbili is the new host record. This is the first report of the genus in this host. Visakhapatnam coast is the new locality record.  相似文献   

15.
A new anisakid nematode, Hysterothylacium patagonense n. sp., is described from the intestine of the temperate bass Percichthys trucha (Cuvier & Valenciennes), a freshwater fish from Lake Aluminé, Patagonia, Argentina. It is characterised mainly by the absence of lateral alae, the length ratio of the caecum and ventricular appendix (1:0.9–1.8), the length of the spicules (0.952–1.292 mm) and the presence of minute spines on the tip of the tail. In the same locality and in Lake Huechulafquen, advanced third-stage and fourth-stage larvae of this parasite were also recorded from the digestive tract of the introduced salmonids, Salvelinus fontinalis (Mitchell), Oncorhynchus mykiss (Walbaum) and Salmo trutta L. This is the second Hysterothylacium species described from freshwater fishes in South America. A key to Hysterothylacium species parasitising American freshwater fishes is provided.  相似文献   

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17.
V Roca  G Garcia-Adell 《Parassitologia》1988,30(2-3):197-202
Spauligodon carbonelli n. sp. (Nematoda: Pharyngodonidae), a parasite from the caecum of the common wall lizard Podarcis muralis (Laurenti, 1768) and the Spanish wall lizard Podarcis hispanica (Steindachner, 1870) (Reptilia: Lacertidae) in the Pirineos Mountains, Spain, is described. S. carbonelli differs from the other known species of the same genus, mainly in the presence and length of the spicule, the morphology of the caudal end in the male and in the structure of the cephalic end of the female.  相似文献   

18.
1. Absorption of purines and their metabolism by the lower intestine were estimated by using the everted gut sacs from the colo-rectum and caecum of the chicken. 2. Adenine, hypoxanthine and uric acid were appreciably absorbed from the colo-rectum and caecum, and an especially high rate was observed in the absorption of uric acid from the colo-rectum. 3. Guanine was not absorbed unchanged from either the colo-rectum or the caecum and a small amount of xanthine was absorbed only from the caecum. 4. Hypoxanthine was also absorbed in uric acid form, to a much lesser extent, in xanthine form from the colo-rectum and caecum, adenine and xanthine in uric acid form from the colo-rectum and adenine in hypoxanthine form from the colo-rectum and caecum. 5. Adenine was metabolized to hypoxanthine and xanthine, guanine and hypoxanthine to uric acid and xanthine, and xanthine to adenine, in both mucosal fluids of the colo-rectum and caecum. The conversion of guanine to uric acid in the caecum was most active, being almost twice as much as that in the colo-rectum.  相似文献   

19.
The spider genus Tayshaneta is revised based on results from a three gene phylogenetic analysis (Ledford et al. 2011) and a comprehensive morphological survey using scanning electron (SEM) and compound light microscopy. The morphology and relationships within Tayshaneta are discussed and five species-groups are supported by phylogenetic analyses: the anopica group, the coeca group, the myopica group, the microps group and the sandersi group. Short branch lengths within Tayshaneta contrast sharply with the remaining North American genera and are viewed as evidence for a relatively recent radiation of species. Variation in troglomorphic morphology is discussed and compared to patterns found in other Texas cave invertebrates. Several species previously known as single cave endemics have wider ranges than expected, suggesting that some caves are not isolated habitats but instead form part of interconnected karst networks. Distribution maps are compared with karst faunal regions (KFR's) in Central Texas and the implications for the conservation and recovery of Tayshaneta species are discussed. Ten new species are described: Tayshaneta archambaultisp. n., Tayshaneta emeraldaesp. n., Tayshaneta fawcettisp. n., Tayshaneta grubbsisp. n., Tayshaneta madlasp. n., Tayshaneta oconnoraesp. n., Tayshaneta sandersisp. n., Tayshaneta sprouseisp. n., Tayshaneta vidriosp. n. and Tayshaneta whiteisp. n. The males for three species, Tayshaneta anopica (Gertsch, 1974), Tayshaneta devia (Gertsch, 1974) and Tayshaneta microps (Gertsch, 1974) are described for the first time. Tayshaneta furtiva (Gertsch, 1974) and Tayshaneta uvaldea (Gertsch, 1974) are declared nomina dubia as the female holotypes are not diagnosable and efforts to locate specimens at the type localities were unsuccessful. All Tayshaneta species are thoroughly illustrated, diagnosed and keyed. Distribution maps are also provided highlighting areas of taxonomic ambiguity in need of additional sampling.  相似文献   

20.
1. Rates of absorption of two hexose (D-glucose and D-galactose) and two pentose (D-xylose and D-arabinose) sugars were measured by in vivo perfusion, in jejunum, ileum and (distal) caecum, in immature hens conditioned to either a standard (ST) or "high fibre" (ST + 20% grass) diet. 2. Each bird was tested in one intestinal segment with all four (U-14C-labelled, 10 mM) sugars, with either the hexoses preceding the pentoses or vice versa. 3. With all treatments, absorption rates of the hexoses were alike, as were those of the pentoses. Hexose absorption was twice as fast as pentose absorption in jejunum and ileum with both dietary pretreatments, whereas in caecum hexose and pentose rates were similarly high, except when pentose (and its associated fluid transfer) was apparently inhibited by prior hexose absorption with the ST diet. 4. With the ST diet, hexose absorption (per unit length and dry weight) was faster in caecum than in jejunum and ileum, and pentose absorption was also fastest in caecum when all pentose data from testing after hexose were excluded. 5. With the ST/grass diet, hexose absorption was faster in jejunum than in ileum and caecum when expressed per unit length, and pentose absorption was fastest in caecum on a dry weight basis. 6. Hexose absorption was faster in jejunum and slower in caecum with the ST/grass pretreatment than with ST. However, the dietary comparison was not conclusive because it involved birds form (two) different hatches (of similar age and weight) tested at different times.  相似文献   

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