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1.
The heterophyid trematode Ascocotyle (Ascocotyle) felippei Travassos, 1928, is redescribed and new data on its life cycle are provided, based on types and metacercariae found in the heart bulb and gills of naturally infected guppies, Poecilia vivipara (new fish intermediate host), from a coastal lagoon in Rio de Janeiro, Brazil. Examination of the type and all voucher specimens of A. (A.) felippei collected by Travassos in the type host and locality in Brazil has shown that they possess only 32 (16 + 16) circumoral spines, rather than 36 (18 + 18) spines as previously reported. Based on the identical number and arrangement of circumoral spines, shape of the body, the presence of a long preoral lobe and posterior muscular prolongation of the oral sucker, short and wide ceca, a simple gonotyl lacking refractile bodies, and the site of infection of metacercariae (predominantly heart bulb), A. (A.) puertoricensis Price, 1932 and A. (A.) tenuicollis Price, 1935, are proposed as new synonyms of A. (A.) felippei.  相似文献   

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4.
During a study of digenean parasites of deep-sea fishes, 81% (17 of 21) of Monomitopus agassizzi (Ophidiidae) from the Gulf of Mexico were infected with Megenteron manteri n. sp. and 10% (2 of 21) were infected with what appears to be a new species of Steringophorus. M. manteri n. sp. differs from M. crassum in having a longer body (3,733–9,394 m), shorter caeca and a uterus that extends posteriorly beyond the ends of the caeca. The species of Steringophorus differs from other species in the genus in having smaller eggs (19–23 m long) and caeca that extend into the posterior half of the hindbody.  相似文献   

5.
A new species of isosporan (Apicomplexa: Eimeriidae) is reported from two magpie jays Calocitta formosa (Swainson) (Passeriformes: Corvidae) from Costa Rica. Oöcysts of Isospora calocitta n. sp. are spherical to subpherical, 28.8 × 27.7 (26.5–31.0 × 25.0–29.5) m and have a shape index (length/width) of 1.04 (1.00–1.11). A micropyle and oöcyst residuum are absent, but 1–3 polar granules are present. Sporocysts are ovoidal, 20.1 × 12.6 (19.0–21.5 × 11.5–13.5) m, and have Stieda and substieda bodies and a shape index of 1.60 (1.47–1.69). A diffuse sporocyst residuum is present and each sporozoite contains two refractile bodies. A list of Isospora spp. in corvid birds is presented.  相似文献   

6.
Specific rates of growth (Cw) of Mesocyclops leuckarti, young male and female instars varied between 0.03–0.26 and 0.03–0.17 g(w.w.)/g(w.w.)/day respectively at 15° and 22°C, whilst at IV–V copepodid stages females showed a higher Cw values. During 1969–1975 the averages of productivity and monthly P/B ratios were 44 (±23) g(w.w.) (= 5g(w.w.)/m2/month) and 3.1 respectively. P/B ratios were highly correlated (r(sup2)=0.98) with temperature changes. Metabolic parameters and P/B ratios were found to be similar to other water bodies in the world indicating an adaptation of M. leuckarti to different conditions.  相似文献   

7.
Summary Two new species of Isospora (Apicomplexa: Eimeriidae) are described from the faeces of passeriform birds of South America. I. cyanocoracis n. sp. is described from Cyanocorax chrysops (Passeriformes: Corvidae) and I. paroariae n. sp. from Paroaria coronata (Passeriformes: Emberizidae). I. cyanocoracis oocysts are spherical or subspherical, 28.7×26.8 m (25.0–30.5×24.5–29.0), with bi-layered wall about 2.0 m thick. Micropyle and oocyst residuum are absent; large polar granule present. Sporocysts are ovoid, 19.3×11.4 m (17.0–21.0×10.5–12.2), with smooth, single-layered wall about 0.8 m thick. Stieda and substiedal bodies and sporocyst residuum are present. Sporozoites 12.2×4.2 m (10.5–15.0×3.5–4.5), possess spherical anterior and posterior refractile bodies. I. paroariae oocysts are spherical or subspherical, 22.3×21.4 m (19.5–25.5×18.5–24.0), and have bi-layered wall about 1.8 m thick. Micropyle, polar granule, and oocyst residuum are absent. Sporocysts ovoid, 15.2×10.0 m (14.0–16.5×8.0–11.5), possess smooth, single-layered wall about 0.7 m thick. Stieda and substiedal bodies and sporocyst residuum are present. Sporozoites elongate, 11.3×3.4 m (10.0–13.5×3.2–4.0), have single, large, posterior refractile body. ac]19840712  相似文献   

8.
A new species of isosporan (Apicomplexa: Eimeriidae) is reported from the Bali mynah Leucopsar rothschildi (Passeriformes: Sturnidae). Oöcysts of Isospora rothschildi n. sp. are spherical to subspherical, 22.3×21.6 (20–26 × 19–23) m, with a shape index (length/width) of 1.03 (1.00–1.15). A micropyle and oöcyst residuum are absent, but one to many polar granules are present. Sporocysts are ovoidal, 15.9×10.6 (15–18 × 9.5–11) m, with Stieda and substieda bodies and a shape index of 1.50 (1.39–1.65). Each sporocyst contains an ellipsoidal sporocyst residuum, 8.0×5.8 (6–11 × 5–8), and each sporozoite contains two refractile bodies. No correlation was found between the presence of coccidian oöcysts in the faeces of some of the birds and Atoxoplasma in blood smears.  相似文献   

9.
A new species of isosporan parasite is described from the faecal contents of the buff-throated foliage-gleaner Automolus ochrolaemus and the olive-backed foliage-gleaner A. infuscatus collected in the rainforests of eastern Ecuador. Sporulated oöcysts are subspherical to ovoidal, 23.4×21.3 (18–28×17–24) m, colourless, with a smooth, double-layered wall with the inner layer darker and thinner; the shape-index (length/width) is 1.1 (1–1.22). Oöcysts contain one polar granule, but lack a micropyle and an oöcyst residuum. Sporocysts are ovoidal, 15.4×9.9 (14–17×–11) m, with a smooth single-layered wall and a small nipple-like Stieda body attached to a small, inconspicuous, acentric substieda body. Sporozoites are vermiform with one prominent posterior, refractile body (c. 4×5 m), and a centrally located nucleus of equal size. Sporozoites are randomly arranged in the sporocysts with a subspherical sporocyst residuum composed of coarse granules.  相似文献   

10.
Isospora geospizae n. sp. is described from the faeces of the small ground finch Geospiza fuliginosa and the medium ground finch Geospiza fortis from Santa Cruz Island in the Galapagos archipelago. I. geospizae oocysts are spherical to subspherical, with a one-layered, smooth, colourless wall, 15.5×14.5 (13–17×12–17) m with a large polar body and no micropyle or residuum. Sporocysts are ovoid, 10×7.5 (10–12×6–9) m with small Stieda and subtieda bodies and a smoothly contoured, but irregular-shaped residuum containing coarse, non-uniform granules. Sporozoites are sausage-shaped with large refractile bodies at each end and randomly arranged in the sporocysts. Three of 34 (8.8%) G. fuliginosa and one of nine (11.1%) G. fortis were infected with I. geospizae.  相似文献   

11.
Fallisia biporcati n. sp. parasitises thrombocytes and lymphocytes of Anolis biporcatus and A. lionotus in Panama. Round or oval schizonts average 13.3 × 11.5 (10.5–16 × 9–13) m, with LW 153.8 (94–208) m2, and produce 38.3 (28–60) merozoites. Gametocytes are variably shaped, from round or oval to nearly triangular or rectangular, and average 12.6 × 9.0 (10–15 × 6–12) m, with LW 113.1 (82–150) m2 and L/W ratio 1.43 (1.0–2.2). Thrombocytes and lymphocytes of A. poecilopus in Panama are parasitised by F. poecilopi n. sp. Schizonts, oval to elongate in shape, 7.7 × 4.7 (5.5–9 × 3–6) m, with LW 36.5 (22–54) m2, are filled with 31.0 (20–51) tiny nuclei or merozoites. Gametocytes are 10.1 × 8.0 (7.5–14 × 6–11) m, with LW 82.0 (45–132) m2, round to elongate with L/W ratio 1.27 (1.0–1.6). F. thecadactyli n. sp. parasitises thrombocytes and lymphocytes of Thecadactylus rapicaudus in Panama and Venezuela. Oval, oblong, or triangular schizonts average 10.3 × 8.0 (7–13 × 5–12) m, with LW 86.6 (37–156) m2, and produce 40.2 (26–61) merozoites. Gametocytes are round, oval, triangular or elongate, 10.4 × 7.0 (7–15 × 5–11) m, with LW 74.8 (40–154) m2 and L/W ratio 1.51 (1.1–2.2). F. dominicensis n. sp. parasitises thrombocytes of A. cybotes on Hispaniola. Schizonts, 6.0 × 4.8 (4–8 × 3–7) m, with LW 29.1 (12–56) m2, round, oval, elongate, oblong or lentiform in shape, produce 12.4 (8–22) merozoites. Gametocytes are 6.6 × 5.0 (5–9 × 4–7) m , with LW 33.8 (20–56) m2, round, oval or elongate, and L/W ratio of 1.34 (1.1–2.0).  相似文献   

12.
Summary A new, favism-inducing variant of glucose-6-phosphate dehydrogenase in erythrocytes is described in a Polish family. The enzyme activity has been 0–4% of normal. The enzyme displayed normal heat stability, electrophoretic mobility 105–110% of normal, Km for NADP: 16–22 M, Km for G-6-P: 26 M, and the utilization of 2-deoxy-G-6-P: 2–3%.  相似文献   

13.
We describe a new heterophyid species, Ascocotyle (Ascocotyle) patagoniensis n. sp., based on specimens collected from the intestines of the South American sea lion Otaria flavescens from Patagonia (Argentina). Ascocotyle (A.) patagoniensis n. sp. is distinguished from the other species of the subgenus by the number of circumoral spines, which are arranged in 2 rows of 18 to 23. The new species also differs from the other species in having a gonotyl without papillae. The specimens exhibited the widest seminal receptacle described for a species of this subgenus. Species of the subgenus Ascocotyle usually infect fish-eating birds or mammals in freshwater or brackish habitats. Ascocotyle (A.) patagoniensis n. sp. is the first species of the subgenus described from a marine mammal. However, no metacercariae of Ascocotyle spp. were found in 542 marine teleosts from 20 species collected in the same locality. The life cycle of the marine species from the Ascocotyle -complex infecting pinnipeds remains elusive.  相似文献   

14.
Biomass and eicosapentaenoic acid (EPA) productivities were investigated in a flat panel airlift loop reactor ideally mixed by static mixers. Growth with ammonium, urea and nitrate as nitrogen source were performed at different aeration rates. Cultures grew on ammonium but the decay of pH strongly inhibited biomass increase. On urea biomass productivity reached 2.35 g L–1d–1at an aeration rate of 0.66 vvm (24 h light per day, 1000 mol photon m–2s–1). Aeration rates between 0.33 vvm and 0.66 vvm and maximal productivities on urea were linearly dependent. Productivity on nitrate never exceeded 1.37 g L–1d–1. In the range of maximum productivity photosynthesis efficiency of 10.6% was reached at low irradiance (250 mol photon m–2s–1). Photosynthesis efficiency decreased to 4.8% at 1000 mol photon m–2s–1. At these high irradiances the flat panel airlift reactor showed a 35% higher volume productivity than the bubble column. At continuous culture conditions the influence of CO2concentration in the supply air was tested. Highest productivities were reached at 1.25% (v/v) CO2where the continuous culture yielded 1.04 g L–1d–1(16 h light per day, 1000 mol photon m–2s–1). The average EPA content amounted to 5.0% of cell dry weight, that resulted in EPA productivities of 52 mg L–1d–1(continuous culture, 16 h light per day) or 118 mg L–1d–1(batch culture, 24 h light per day).  相似文献   

15.
A new species of Alcataenia is described from razorbills Alca torda Linnaeus from the southern region of the North Sea in the coastal waters of Belgium. It differs from known species of the genus in having 18–20 rostellar hooks measuring 63–74 m in length. Other attributes include a cirrus-sac 145–228 m in length, 36–49 testes and a vitelline gland measuring 114–202 × 59–112 m. This is the first species of Alcataenia described from razorbills and appears to be the only member of the genus which is endemic to the North Atlantic basin.  相似文献   

16.
Parasitological examination of European otter originating from Extremadura, Spain revealed the presence of a new isosporan species. Oöcysts of Isospora lutrae n. sp. are spherical to subspherical, 31.2 (27.5–32) × 29.6 (28–31) m and have a smooth wall c. 1 m thick. Sporocysts are ellipsoidal, 18.2 (17–19) × 14.4 (14–16) m and lack Stieda and substieda bodies. A spherical sporocyst residuum is present, consisting of granules scattered among the sporozoites. Sporozoites are spindle-shaped, 12.4 × 2.5 m and have anterior and posterior refractile bodies. Based on its unique morphologic structure and host, I. lutrae is considered to be new.  相似文献   

17.
Annual studies of kinetics of alkaline phosphatase (APA) activity and phosphorus availability for microplankton in the photic zone of an eutrophic lake are reported. The total APA activity of microplankton varied strongly. Vmax was highest during summer P depletion, and in autumn and winter total APA activity was low. The total APA specific activity of the microplankton was also highest (average 3.55 pmole PO4 3– ng ATP–1 min–1) when ambient orthophosphate concentrations were very low. Both Vmax and specific APA activity were not dependent on the biomass of microplankton; they were strongly affected by P available for microplankton. A differential filtration technique was used for separation of microplankton into two size classes, i.e., algal, larger than 3m, and bacterial fraction with size 0.2–3.0m. The algal size fraction had lower specific APA activity (average 1.224 pmole PO4 3– ng ATP–1 min–1) and higher KM values (38.8mole × liter–1) than microorganisms which were smaller than 3m (2.011 pmole PO4 3– ng ATP–1 min–1 and 25.4mole liter–1, respectively). The KM values of free, dissolved APA (36.8mole liter–1) indicated that free APA was probably released by algae. Phytoplankton were major APA activity producers in the photic zone of the lake from March to November, and their activity constituted, on the average, 48.6% of the total APA activity in the water. Bacteria were the dominant APA activity producers in winter (41.3–44.9%); however, during other periods they contributed significantly (average 21.7%) to total APA activity. When surplus constituted less than 10% of particulate P in seston, phytoplankton produced high specific APA activity, and when surplus P was higher than 15%, the specific APA activity of phytoplankton size fraction rapidly decreased. APA of the bacterial size fraction of the seston was not affected by P concentrations. Orthophosphate was a competitive inhibitor of APA produced by microorganisms of the size fraction larger than 3.0m, and increasing concentrations of inorganic phosphate caused an increase in KM values. The hypothetical metabolic-coupling between phytoplankton and bacterioplankton in the phosphorus cycle in conjunction with carbon metabolism in the lake is discussed.  相似文献   

18.
Summary Studies of the dorsal ocelli of the wasp Paravespula vulgaris (L.) led to the following results: Under a biconvex corneal lens, 150 m in thickness, about 600 receptor cells are located. The rhabdomeres of two adjacent cells form a closed plate-like rhabdom (0.5–1.0 m in thickness, 6 m in width and 10–25 m in depth or length).In the lateral ocellus the receptor cells synapse up to 8 ocellar nerve fibers, and in the median ocellus they synapse up to 16 (20–30 m thick) ocellar nerve fibers.The ocellar synaptic plexus may display three types of synapses between the two types of neurons: (i) Receptor-cell axons are presynaptic to dendrites of the first-order interneurons. (ii) Dendrites of the first-order interneurons are presynaptic to receptor-cell axons. (iii) The subunits of a dendrite of first-order interneurons form synapses with each other.The present work was partially supported by the Stiftung Volkswagenwerk  相似文献   

19.
Three isolates ofSpirulina platensis (Norst) Geitler marked BP, P4P and Z19/2 were compared with respect to their response and acclimation capability to high photon flux densities (HPFD). Cultures exposed to HPFD (1500–3500 mol photon m–2 s–1) exhibited a marked decrease in light-dependent O2 evolution rate. P4P was more sensitive to HPFD than the two other isolates. All three isolates recovered from photoinhibition when placed under low PFD. The BP isolate was able to recover also in the dark but to a lower extent and at a lower rate, while no recovery was observed in the other two isolates under dark conditions. No recovery was observed when protein synthesis was inhibited using chloramphenicol. Cultures grown at 200 mol photon m–2 s–1 differed from cultures grown at 120 mol photon m 2 s-1 by their lower maximal photosynthetic rate (P max ) and higher light saturation (I k ) value, while being more resistant to HPFD stress. The ability ofSpirulina isolates to acclimate and withstand HPFD may provide useful information for the selection of strains useful for outdoor mass cultivation.Author for correspondence  相似文献   

20.
Lemdana latifi n. sp. was found in connective tissues around the trachea and crop and in the body-cavity of seven of 14 Malayan red jungle fowl Gallus gallus spadiceus. The new species is described and illustrated. Morphologically it is most closely related to Lemdana pavonica and Lemdana francolini. Lemdana latifi is distinguished from the eight valid species of Lemdana by the mean spicular ratio of 1.7:1; the right spicule with a right margin 18–29% (15–31 m; mean 24 m) longer than the left margin; the distal half of the left spicule twisted and S-shaped; and the absence of unpaired papillae at tip of male tail. The new species has smaller adults, a shorter left spicule and a shorter glandular oesophagus than those of L. pavonica and a wider male, shorter spicules and a longer muscular oesophagus than those of L. francolini. The male of L. latifi is 7–9 (8.1)mm long, the left spicule 164–215 (184)m long and the right spicule 98–117 (108)m long. The female is 17–23 (21)mm in length. Sheathed microfilariae from blood smears are 78–100 m long and those from the uterus are 89–103 m long. This is the sixth valid species of Lemdana in the Phasianidae.  相似文献   

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