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1.
在中国南海的矛尾翻车鲀(Masturus lanceolatus)中发现了两种复殖吸虫,Accacoelium contortum(Ruldolphi,1819)和Accacladocoelium petasiporum(Odhner,1928),它们隶属于凸腹科(Accacoeliidae Odhner,1911),这两种复殖吸虫的子宫走向和以前的描述不同,对它们的形态进行了重新描述。另外,研究中的A.contortum是在宿主肠道中发现,而不是如从前记录的发现在宿主的鳃上。这两种虫及其所在的属都是首次在中国发现和报道。  相似文献   

2.
A list of fish parasites (Digenea) from the coastal waters of Terra Nova Bay (Ross Sea, Antarctica) concerns 10 identified species, namely Macvicaria pennelli, Neolebouria terranovaensis, Helicometra pisanoae, Lepidapedon balgueriasi, L. garradi, Genolinea bowersi, Derogenes johnstoni, Gonocerca phycidis, Elytrophalloides oatesi, Lecithaster macrocotyle, 1 genus Aporocotyle sp. and one specimen undetermined. The total number of species known from the Ross Sea increased from 9 to 12. This number is smaller than those of other Antarctic areas, such as Western Antarctic and Weddell Sea where more extensive investigations were carried out to date.  相似文献   

3.
Morphology of the Helicometra fasciata Rud., 1819 parthenogenetic generation from the Black Sea gastropods Gibbula adriatica (Phil.) was studied for the first time. Data on seasonal dynamics of the hemipopulation of daughter sporocysts are given. Daughter sporocysts of H. fasciata infest 10 +/- 0.2 % of G. adriatica (mainly specimens of larger size and elder age classes). As a rule, local microhemipopulations of daughter sporocysts castrate mollusc hosts. Reproduction of H. fasciata daughter sporocysts is asynchronous: daughter sporocysts born specimens of next sporocyst generation during autumn and winter, and then they begin producing cercaria. In winter development of the cercaria embryo is blocked. Second change of the character of the each sporocyst' posterity is impossible because of the annual life cycle of G. adriatica. Endogenous agglomeration of the H. fasciata daughter sporocysts is extremely little: individuals of next sporocyst generation develop from no more than 2 % of embryonic balls. Energy resources of the mollusc host are used by the H. fasciata daughter sporocysts mainly for producing cercaria; this fact can be interpreted as an adaptation of H. fasciata to using medium-sized, short-living mollusc hosts.  相似文献   

4.
Species within the genus Helicometra are difficult to distinguish on morphological grounds alone, and are best discriminated with the aid of biochemical techniques. In the work reported here, the electrophoretic mobility of malate dehydrogenase isoenzyme of the Mdh-1 locus was used to characterize 375 individuals of Helicometra obtained from various teleost species (Anguilla anguilla, Conger conger, Gobius niger or Ciliata mustela) caught off the coast of northwest Spain. The results suggest that all specimens belong to only one species, probably H. fasciata. Observed genotype frequencies did not differ from those expected under the assumptions of Hardy-Weinberg equilibrium, even when the genic frequencies differ considerably respecting a Mediterranean population.  相似文献   

5.
This paper describes the ultrastructure of the mature spermatozoon of the digenean Helicometra epinepheli. The ultrastructural elements observed are: two axonemes with a 9+"1" pattern of Trepaxonemata, four attachment zones, a nucleus, two mitochondria, external ornamentation of the plasma membrane, spine-like bodies and cortical microtubules. A particularity of this spermatozoon is the presence of an apical cone. However, the spermatozoon presents the general pattern of the Opecoelidae and thus differs from Helicometra fasciata (which appears as an exception in this family) by several ultrastructural features: the presence of external ornamentation and spine-like bodies and the arrangement of cortical microtubules around the first mitochondrion in the region of the ornamentation. Each ultrastructural feature is discussed and compared with the literature to highlight characters which could be useful for phylogeny.  相似文献   

6.
Helicometra Odhner, 1902 is reported from temperate Australian marine teleosts in which it appears to be rare. Of 285 species of fishes from 84 families examined, only 10 species from 9 families were infected. One infection, that in Platycephalus speculator caught from off the coast of Western Australia, is highly distinctive and the name Helicometra sprenti n. sp. is proposed for this species. The other infections were from members of the Antennariidae, Apogonidae, Kyphosidae, Labridae, Paralichthyidae, Pinguipedidae, Scorpaenidae and Sparidae, all from off southern Queensland and New South Wales. There is no evidence that infections are common in any of these hosts, which have little relationship to each other. Measurements and figures are presented for representatives from all the host species. Only minor variation was found in features such as body dimensions and the extent of the vitelline follicles, and it is concluded that the specimens probably represent a single species with a very low host-specificity. We suspect that the general scarcity of the worm is consistent with the presence of only one species, although the possibility that a species-complex is present cannot be ruled out. The specimens are broadly consistent with H. fasciata (Rudolphi, 1819), a species first described from Europe, and they are tentatively identified as this species, although it seems likely that ultimately they will prove to represent a different taxon. Determination of the ultimate identity of this form will require the application of molecular and life-cycle studies of worms from different hosts and localities.  相似文献   

7.
A quantitative and qualitative analysis of the parasite fauna of the sciaenid Stellifer minor (Tschudi) from Chorrillos, Perú, was made. Some characteristics of the infectious processes, in terms of intensity and prevalence of infection, as a function of host sex and size, are given. Moreover, comments on the characteristics of the parasite fauna, related with host role in the marine food webs are included. The parasite fauna of Stellifer minor taken off Chorrillos, Perú, include the monogeneans Pedocotyle annakohni, Pedocotyle bravoi, Rhamnocercus sp. and Cynoscionicola sp., the digenean Helicometra fasciata, the adult acantocephalan Rhadinorhynchus sp. and the larval Corynosoma sp., the nematode Procamallanus sp., the copepods Caligus quadratus, Clavellotis dilatata and Bomolochus peruensis and one unidentified isopod of the family Cymothoidae. A distinctive characteristic of the parasite fauna (Metazoa) of S. minor is the almost absence of larval forms.  相似文献   

8.
We studied the parasite fauna and food contents of 38 juvenile of Notothenia c.f. angustata specimens captured in the intertidal of Island Santa María and Maule, in the Arauco Gulf, Chile. Trophic habits of Notothenia c.f. angustata were not different between localities, which was mainly algae. A total 11 parasitic taxa among were found with the digenean Lecitasther macrocotyle, cestode larvae Tetraphyllidea and Diphyllidea and nematode Ascarophis sp. being the dominant taxa. The abundance of parasites was similar in the two localities, although the infracommunity richness was higher in fish from Maule. The most abundant parasite was L. macrocotyle in hosts from Isla Santa María, while those from Maule they were the Diphyllidea larvae and nematodes Ascarophis sp. The body length of the hosts was not a good predictor of the variations in abundance and richness at infracommunities, probably because of the early ontogenetic stage of fishes.  相似文献   

9.
A revision of the Calicotylinae Monticelli, 1903(Monogenea: Monocotylidae)   总被引:1,自引:0,他引:1  
A total of 153 elasmobranchs (46 species), either freshly collected from the Gulf of Mexico, USA and Tasmania, Australia or museum specimens collected from various localities worldwide, were examined for calicotyline (Monocotylidae) monogeneans. Thirty-five elasmobranchs, representing 17 species, were infected with Calicotyle spp. which we identified as the following previously described species: C. asterii (Szidat, 1970) Timofeeva, 1985, C. kroyeri Diesing, 1850, C. macrocotyle Cordero, 1944, C. similis (Szidat, 1972) Timofeeva, 1985, C. splendens (Szidat, 1970) Timofeeva, 1985, C. stossichi Braun, 1899 and C. urolophi Chisholm, Beverley-Burton & Last, 1991. The Calicotylinae, which comprises the genera Calicotyle and Dictyocotyle, is revised based on supplementary material as well as deposited type-material. We consider 14 of the 17 nominal Calicotyle spp. to be valid. C. rosinae Kusnetzova, 1970 is synonymised with C. macrocotyle, C. sjegi Kusnetzova, 1970 is considered a species inquirenda and C. inermis Woolcock, 1936 a species incertae sedis. Additional data and illustrations to show the morphological features of the hamuli and male copulatory organ, the form of the intestinal caeca, vaginae and ovary and the distribution of the vitellarium are provided for all valid species. The distribution of the 14 hooklets in the adult haptor of Dictyocotyle coeliaca Nybelin, 1941 is illustrated for the first time. We provide new host and locality records for C. asterii, C. kroyeri, C. macrocotyle and C. stossichi and new locality records for C. similis and C. splendens. A key to species of the Calicotylinae is also included. Host-specificity, geographical distribution and the need for information regarding the development of individuals from juvenile to adult are discussed.  相似文献   

10.
A new approach to the genome characterization of trematode sporocysts is described to investigate the life cycles of three species of Helicometra and to compare their degree of specificity for mollusc and teleost hosts.  相似文献   

11.
Caterpillars of the hawkmoth Eumorpha fasciata are highly polymorphic for colour, with green, pink, and pink-and-yellow forms in the second through fourth instars, and green and multicoloured forms in the fifth instar. Four years of field censuses on four foodplant species determined that all morphs were found on all plant species; morph frequencies were homogeneous on each plant species over time; and morph frequencies differed consistently among plant species. When larvae were reared from eggs on three of the hostplant species in the laboratory, differences in morph frequencies paralleled the census results. Thus foodplant quality is one factor affecting larval colour in E. fasciata. A literature survey reveals that foodplant effects on larval colouration may be widespread in the family Sphingidae, but most reports are anecdotal rather than experimental. The implications of this mechanism of colour determination are discussed.  相似文献   

12.
Bird mixed flocks including Cypsnagra hirundinacea and Neothraupis fasciata as species with sentinels were studied in "campo-cerrado" in order to investigate the possible relationship between alertness and the mixed flock leadership. This study was conducted from March to September 1996 and mixed flocks were observed on average for 2:30h. The time with sentinels were recorded for C. hirundinacea and N. fasciata. The sentinels of Cypsnagra hirundinacea performed most of the vigilance (time with sentinel was on average 42 +/- 17%, 41 +/- 17% of which by C. hirundinacea, whereas only 1.2% by N. fasciata) and gave all the alarm calls recorded (54% of the encounters with raptors stimulated alarm calls). A relationship was verified between time with sentinel and the rate of encounters with raptor (ANOVA, F = 3.0. P < 0.05). The results of this study are an evidence for the anti-predatory function of mixed flocks, in campo-cerrado, and the alertness as a major feature of a leader species, since C. hirundinacea always led those flocks.  相似文献   

13.
In this study, the adsorption properties of two different marine algae (Ulva fasciata (green algae) and Sargassum sp. (brown algae)) were investigated. Equilibrium isotherms and kinetics were studied to evaluate the relative ability of the two algae to sequester Cu(II) from aqueous solutions. The maximum biosorption capacity obtained was 73.5 mg g(-1) for U. fasciata and 72.5 mg g(-1) for Sargassum sp. at a solution pH of 5.5 +/- 0.5. A significant fraction of the total copper(II) uptake was achieved within 30 min. The copper(II) uptake by the biosorbents was best described by pseudo-second-order rate model.  相似文献   

14.
The chemical nature and mode of stabilization of egg-shell protein in digenetic trematode Helicometra pulchella (Rudolphi, 1819) have been investigated using histochemical techniques. It was found that the egg-shell is stabilized by quinone-tanning together with dityrosine. Other structural proteins (elastin, collagen and keratin-like proteins), glycogen and acid mucopolysaccharides were absent in egg-shell. Tyrosine was present in vitelline cells and immature egg-shell indicating that the proteins involved in quinone-tanning were tyrosine rich and tyrosyl residues are modified to form dityrosine in mature egg-shell.  相似文献   

15.
Aspidodera sogandaresi n. sp. (Heterakoidea: Aspidoderidae) from Dasypus novemcinctus Linnaeus, 1758 is herein described. This nematode occurs in armadillos from as far south as the canal zone of Panama, north through central Mexico, and into the southern United States. Previously identified as Aspidodera fasciata (Schneider, 1866), this new species has blunt projections on the lips and lateral expansions at the distal tips of the spicules, whereas A. fasciata has conspicuous digitiform projections on the lips, and a terminal round expansion at the tips of the spicules. Other species of the family present in North America include Aspidodera binansata Railliet and Henry, 1913; Aspidodera vazi Proen?a, 1937; and Lauroia trinidadensis Cameron, 1939.  相似文献   

16.
为了探究大型海藻裂片石莼(Ulva fasciata)防治赤潮的可行性,研究将赤潮异弯藻(Heterosigma aka-shiwo)分别暴露在浓度为0.6、1.2、2.4和4.8 g/L的裂片石莼藻粉中,观察赤潮异弯藻光合系统的响应.实验用植物效率分析法测定了赤潮异弯藻的光合效率,用透射电子显微镜法观察了赤潮异弯藻叶...  相似文献   

17.
温度对花斑副沙鳅仔鱼发育、摄食及不可逆点的影响   总被引:1,自引:0,他引:1  
2011年4~5月,研究了温度对花斑副沙鳅(Parabotia fasciata)早期仔鱼的发育、初次摄食时间、群体摄食率及不可逆点(PNR)的影响。结果发现,花斑副沙鳅仔鱼出膜后2 d已开始摄食;初次群体摄食率最高值出现在卵黄囊耗尽后的1~2 d,花斑副沙鳅仔鱼的摄食强度随温度升高而增大。仔鱼抵达PNR的时间随温度升高而缩短:22℃时,仔鱼的PNR出现在出膜后的8.0~9.0 d;26℃时,PNR为7.0 d;28℃时,PNR为5.5 d;30℃时,PNR为5.0 d。最大初次摄食率至PNR之间为不可逆饥饿期,22℃时为3.5 d,30℃时仅为1.5 d,说明温度越高,仔鱼耐受饥饿的能力越差,越不利于仔鱼的存活。研究认为,温度对花斑副沙鳅仔鱼发育、摄食及不可逆点的影响较大;在苗种培育过程中,应根据温度确定投饵时间,适时投饵对仔鱼的成活显得尤其重要。  相似文献   

18.
Hsu YT  Lee TM 《Physiologia plantarum》2012,144(3):225-237
A gene (UfCBR) encoding carotene biosynthesis-related (CBR) protein that potentially functions for the dissipation of excessive energy has been cloned from the intertidal green macroalga Ulva fasciata Delile. Hypersalinity and high light ≥300 μmol m(-2) s(-1) increased both UfCBR mRNA level and non-photochemical quenching (NPQ). The increase of UfCBR mRNA level and NPQ by high light was inhibited by treatment of photosynthetic electron transport inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea or 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, but not by stigmatellin, an inhibitor that blocks electron transfer from quinol oxidase to iron-sulfur protein in cytochrome b(6) f complex. Treatment of dimethylthiourea, an H(2) O(2) scavenger, under 1200 μmol m(-2) s(-1) condition inhibited H(2) O(2) accumulation but did not affect UfCBR mRNA level, while treatment of H(2) O(2) in 150 μmol m(-2) s(-1) condition decreased UfCBR mRNA level. Thus, an reactive oxygen species-independent redox control via a more reduced state downstream the cytochrome b(6) f complex is involved in high light up-regulation of UfCBR expression in U. fasciata. The expression of UfCBR in U. fasciata against oxidative stress occurring in high light or high salinity in relation to NPQ is discussed.  相似文献   

19.
The enzymatic glucosylations of naringin, performed using alpha-D-glucosidase, identified in the Mediterranean mollusc Aplysia fasciata is reported. The enzyme actively operates on maltose and has an interesting transglycosylation potential using this donor. We also investigated the use of this marine alpha-glucosidase for a food-compatible glucosylation of naringin to produce new enzymatically modified carbohydrate possessing naringin derivatives. The regioselective formations of the beta-gluco-C6 alpha-glucosyl derivative and of the corresponding isomaltosyl diglucoside of naringin were obtained in high yield and efficiency of reaction. Suspensions of naringin can be used up to approximately 90 mg/mL initial acceptor concentration. In different experiments it was demonstrated that the enzyme was still active after 48 h in presence of this high amount of acceptor and that one of the diasteromers of the naringin is preferred by the enzyme from A. fasciata during glucosylation/deglucosylation enzymatic steps. Finally, the feasibility of efficient naringin glucosylation in grapefruit juice was also demonstrated at optimal pH of the enzyme and low maltose concentrations.  相似文献   

20.
Estimating energy costs by respirometry is fundamental to many studies of the ecology, behavior and evolution of reptiles. However, traditional respirometry procedures seldom incorporate objective techniques for removal of outliers from estimates of metabolic parameters. We demonstrate how computer-automated respirometry equipment, which records many respiratory measurements over short intervals, can be coupled with mathematical procedures to produce robust estimates of pre- and post-prandial metabolism in banded water snakes (Nerodia fasciata fasciata). Standard metabolic rate of N. f. fasciata was estimated to be 1.21 ml O2/h (mass = 30.21 +/- 0.74 g) at 25 degrees C. After ingestion of a fish equaling 20% of their body mass, snakes exhibited a fivefold increase in metabolic rate with peak O2 consumption rate (VO2) reaching 6.5 ml O2/h. Total cost of digestion was 5.44 kJ, equivalent to approximately 21% of the energy in the meal. Repeated measurements of metabolism in the same individuals revealed that our methods yielded similar results, even when individuals exhibited different patterns of VO2 variation between respiratory trials. Our results underscore the importance of obtaining many VO2 measurements, coupled with objective removal of outlier values from estimates of metabolic rate, especially when metabolic values are to be interpreted in a comparative context.  相似文献   

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