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1.
Proctotrema bartolii n. sp. (Digenea: Monorchiidae) is described based on naturally and experimental obtained adults from the marine fishes Odontesthes smitti (Lahille), O. nigricans (Richardson) (Atherinopsidae) and Eleginops maclovinus (Cuvier) (Eleginopidae) off Patagonia, Argentina, in the Southwestern Atlantic Ocean. Its generic identification is based on the presence of a unipartite terminal organ with the metraterm uniting with its distal region, an unarmed genital atrium, a single testis, a vitellarium follicular lateral to the ovary and ventral sucker, and uterine coils occupying most of hindbody. The new species differs from P. bacilliovatum Odhner, 1911, P. amphitruncatum Fischthal & Thomas, 1969 and P. guptai Ahmad & Dhar, 1987 in having a smaller body (305–650 vs 1,600–3,080, 1,500–1,800 and 2,150–2,670 μm, respectively), a round vs funnel-shaped oral sucker, a smooth vs lobed ovary, a saccular rather than tubular excretory vesicle, the number of vitelline follicles (12–16 vs 8–9, 9 and 6–8, respectively), and wider eggs (25–31 × 15–20 vs 28–37 × 9–12, 24–28 × 7–10, and 24–30 × 8–10 μm, respectively). Moreover, the new species differs from P. bacilliovatum and P. amphitruncatum in having a saccular rather than a coiled seminal vesicle, and from P. bacilliovatum and P. guptai in having its tegument completely vs partly spined. Proctotrema Odhner, 1911 is considered to be restricted to these four species. This is the first report of a species of this genus from South American waters.  相似文献   

2.
Two new species of the cryptogonimid genus Parspina Pearse, 1920 are described from gymnotiform fishes of the Paraná River basin, P. carapo n. sp. from the banded knifefish Gymnotus carapo Linnaeus and P. virescens n. sp. from the glass knifefish Eigenmannia virescens (Valenciennes). Parspina carapo differs from P. virescens in the number of oral spines (32–39 vs 30–33) and their length (28–47 vs 16–28 μm), the distribution of tegumental spines and their anchorage, the types of sensory papillae on the body surface (three vs two types), the extent of body length posterior to the caeca (5 vs 13% of the total body length), the dimensions of the pars prostatica (52 × 34 vs 24 × 10 μm), and in the absence of a gonotyl (vs presence). Both P. carapo and P. virescens differ from P. bagre Pearse, 1920 and P. argentinensis (Szidat, 1954) in the number of oral spines (20–21 and 21–28 in the latter pair) and their length (28–32 and 35–60 μm), and in total body length. Additionally, the two new species differ from P. argentinensis in the arrangement of the vitelline follicles (one continuous band vs two groups on each side of the body) and in having a smaller pars prostatica (149 × 49 μm in the latter). Parspina carapo is the fifth intestinal helminth found in G. carapo, and P. virescens is the first found in E. virescens.  相似文献   

3.
A new homobasidiomycete, Asterostroma macrosporum, was found in mangrove forests of Iriomote Island, Japan. This species is morphologically characterized by having resupinate basidiomata, a monomitic (asterodimitic) hyphal system, simple septate generative hyphae, dextrinoid asterosetae, four sterigmate basidia and globose, tuberculate and amyloid basidiospores measuring 8.5–11 × 7.5–9 μm. It is similar to A. muscicola, but basidiospores in the latter are smaller (7–8 × 5.5–7 μm). Furthermore, phylogenetic analysis using internal transcribed spacer (ITS) region revealed that A. macrosporum is distinctly separated from A. muscicola. In Japan, A. muscicola is widely distributed in warm-temperate to subtropical regions, growing on a variety of broadleaved trees including mangroves, while A. macrosporum has been found only on mangroves.  相似文献   

4.
A new species of Hirsutella, H. proturicola, isolated from a subterranean proturan (Baculentulus densus; Protura, Hexapoda), is described and illustrated. Hirsutella proturicola is characterized by producing monoblastic phialides of 24–51.5 × 2.5–5 μm with a slightly roughened neck, fusiform and curved conidia of 9–18 × 2.5–4 μm that have a truncate base and a papillate projection often capped with sheath-like mucilage, and pluricellular, globose to subglobose chlamydospores of 21–48 × 21–41.5 μm. This species is morphologically and phylogenetically close to H. rostrata, an acaropathogenic species, but can be distinguished from the size of the phialides and the size and shape of the conidia.  相似文献   

5.
A new lecanicephalidean species of Aberrapex Jensen, 2001 is described from the blue-spotted fantail ray Taeniura lymma (Forsskål) collected off the eastern coast of Sabah in Malaysian Borneo. This is the first record of a lecanicephalidean tapeworm from the island of Borneo and the first record of Aberrapex from this host species. A. manjajiae n. sp. is easily distinguished from its two congeners, A. senticosus Jensen, 2001 and A. arrhynchum (Brooks, Mayes & Thorson, 1981) Jensen, 2001, based on its overall smaller size (928–1,971 vs 1,485–6,333 and up to 3,350μm long, respectively) and fewer testes (10–19 vs 20–40 and 18–25, respectively). In addition, A. manjajiae n. sp. is readily distinguished from A. senticosus based on a more anteriorly positioned genital pore (76–85 vs 52–72% of proglottid length from posterior end) and its distal bothridial microthrix pattern. A. manjajiae n. sp. can be further distinguished from A. arrhynchum based on its smaller scolex (82–101 × 119–164 vs 177–186 × 233–326μm). The host distribution of Aberrapex is expanded from the Myliobatidae to include the Dasyatidae.  相似文献   

6.
Ypsilonidium bananisporum sp. nov. belonging to Ceratobasidiales is described and illustrated. This fungus has all the characteristics of the genusYpsilonidium including reticulate-hypochnoid basidiomes, broad hyphae branching at right angles, broadly clavate basidia with two sterigmata, and basidiospores germinating by repetition. It differs from all hitherto known species in the genus by producing suballantoid to banana-shaped basidiospores, measuring 19.5–22×5.5–6 μm. Contribution No. 314 of the Tottori Mycological Institute.  相似文献   

7.
In the current study, two new coccidian species (Protozoa: Apicomplexa: Eimeriidae) obtained from short-crested flycatcher Myiarchus ferox (Gmelin) are reported from Brazil. Isospora feroxis n. sp. has o?cysts which are spheroidal to sub-spheroidal, 18.7 × 18.0 μm, with a smooth and bi-layered wall, c. 1.2 μm. The micropyle and o?cyst residuum are absent, but two polar granules are present. Its sporocysts are broadly ellipsoidal and 11.7 × 8.5 μm. Stieda and substieda bodies are present. A sporocyst residuum is present and the sporozoites have a refractile body and nucleus. O?cysts of Eimeria sicki n. sp. are spheroidal to sub-spheroidal, 30.3 × 28.5 μm, with a smooth and bi-layered wall, c. 1.3 μm. The micropyle, o?cyst residuum and polar granule are absent. Its sporocysts are ellipsoidal, 18.4 × 10.0 μm. Stieda and substieda bodies are present. A sporocyst residuum is present and sporozoites have a refractile body and nucleus.  相似文献   

8.
Two new nematode species, Ascarophis longiovata n. sp. and Neoascarophis longispicula n. sp. (Cystidicolidae), are described from the digestive tract of the marine deep-water fish, the Mediterranean grenadier Coryphaenoides mediterraneus (Giglioli), from the Mid-Atlantic Ridge. The former species is characterised mainly by the structure of the mouth (large pseudolabia, each with well-developed dorsal and ventral extension and small apical protrusion; submedian labia almost absent), the large, elongate-oval, non-filamented eggs (60–66 × 18–27 μm), a cervical inflation of the cuticle, bifurcate deirids, and the length of the spicules (315–360 and 120–147 μm), whereas the latter (only males available) can be distinguished by the length of the spicules (960–1,149 and 258–351 μm) and their length ratio (1:1.91–2.71), the shape of the deirids (bifurcate, with long, narrow posterior arms), and the location of the excretory pore and deirids well posterior to the level of the nerve-ring.  相似文献   

9.
Lignosus hainanensis sp. nov., is described and illustrated on the basis of collections originating from tropical forest in Hainan Province, southern China. Both the morphology and phylogeny support this new species. It is characterized by its centrally stipitate basidiocarps arising from a distinct sclerotium, yellowish brown to cinnamon-brown pileal surface, cream to cream-buff pore surface, trimitic hyphal system with clamped generative hyphae, and oblong ellipsoid to cylindrical basidiospores. Lignosus hainanensis may be confused with L. rhinocerus, also occurring in southern China, but L. rhinocerus can be distinguished by its smaller pores (6–8 per mm) and smaller and distinctly broadly ellipsoid basidiospores (4–5 × 2.8–3 μm).  相似文献   

10.
This study reports on the optimization of protoplast yield from two important tropical agarophytes Gracilaria dura and Gracilaria verrucosa using different cell-wall-degrading enzymes obtained from commercial sources. The conditions for achieving the highest protoplast yield was investigated by optimizing key parameters such as enzyme combinations and their concentrations, duration of enzyme treatment, enzyme pH, mannitol concentration, and temperature. The significance of each key parameter was also further validated using the statistical central composite design. The enzyme composition with 4% cellulase Onozuka R-10, 2% macerozyme R-10, 0.5% pectolyase, and 100 U agarase, 0.4 M mannitol in seawater (30‰) adjusted to pH 7.5 produced the highest protoplast yields of 3.7 ± 0.7 × 106 cells g−1 fresh wt for G. dura and 1.2 ± 0.78 × 106 cells g−1 fresh wt for G. verrucosa when incubated at 25°C for 4–6 h duration. The young growing tips maximally released the protoplasts having a size of 7–15 μm in G. dura and 15–25 μm in G. verrucosa, mostly from epidermal and upper cortical regions. A few large-size protoplasts of 25–35 μm, presumably from cortical region, were also observed in G. verrucosa.  相似文献   

11.
Numerous (0.5 to 4.8 × 105 cells/ml), small phytoplankton (smaller than 0.5–1 × 1–2 μm in cell size, picophytoplankton) were distributed in the halocline (depth 2–12 m, 4–14 practical salinity units) of the saline meromictic lake, Lake Suigetsu (35°35′ N, 135°52′ E), located in the central part of the coast of Wakasa Bay along the Japan Sea in Fukui Prefecture, Japan. Vertical distribution of phytoplankton revealed that the maximum number of picophytoplankton was always observed near or a little deeper than the oxic-anoxic boundary layer (depth 5–6 m); they were dominant phytoplankton in the water layer deeper than the oxic-anoxic boundary from July to late September 2005. Spectral analysis of autofluorescence emitted from the particle fractions smaller than 5 μm measured with a spectrofluorometer and from individual cells measured with a microscope photodiode array detector revealed that the major component of picophytoplankton was phycoerythrin-rich, unicellular cyanobacteria (picocyanobacteria). Eukaryotic phytoplankton about 2.5 μm in diameter were also found, but the numbers were low. Fluorescence intensity of chlorophyll a at 685 nm (room temperature) emitted from the particle fractions smaller than 5 μm was increased by the addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea. These observations indicated that at least some picophytoplankton had a functional photosystem II in the halocline where sulfide, the potential inhibitor of oxygenic photosynthesis, was always present. The large abundance together with their physiological potency suggest that picophytoplankton are one of the important primary producers in the halocline of Lake Suigetsu. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   

12.
From November 1992 to February 1995 a quantitative and qualitative phytoplankton study was conducted at a permanent station (Kerfix) southwest off the Kerguelen Islands, in the vicinity of the Polar Front (50°40′S–68°25′E). Phytoplankton populations are low in this area both during summers and winters. They consist, in order of decreasing cell abundance, of pico- and nanoflagellates (1.5–20 μm), coccolithophorids (<10 μm), diatoms (5–80 μm) and dinoflagellates (6–60 μm). Flagellates form the dominant group throughout the year and attain the highest summer average of 3.0 × 105 cells l−1. Next in abundance year-round are coccolithophorids with the dominant Emiliania huxleyi (highest summer 1992 average 1.9 × 105 cells l−1), diatoms (summer 1992 average 1.0 × 105 cells l−1) and dinoflagellates (average 3.8 × 104 cells l−1). Winter mean numbers of flagellates and picoplankton do not exceed 8.4 × 104 cells l−1; those of the three remaining algal groups together attain 2 × 104 cells l−1. Summer peaks of diatoms and dinoflagellates are mainly due to the larger size species (>20 μm). The latter group contributes most to the total cell carbon biomass throughout the year. Dominant diatoms during summer seasons include: Fragilariopsis kerguelensis, Thalassionema nitzschioides, Chaetoceros dichaeta, C. atlanticus, Pseudonitzschia heimii, and P. barkleyi/lineola. This diatom dominance structure changes from summer to summer with only F. kerguelensis and T. nitzschioides retaining their first and second positions. Any one of the co-dominant species might be absent during some summer period. The variable diatom community structure may be due to southward meandering of the Polar Front bringing “warmer” species from the north, and to the mixing of the water masses in this area. The entire community structure characterized both during summer and winters by the dominance of flagellates can be related to deep mixing (ca. 40–200 m) of the water column as the probable controlling factor. Received: 13 November 1997 / Accepted: 11 May 1998  相似文献   

13.
Isotherms of the EtBr adsorption on native and denatured poly(dA)poly(dT) in the temperature interval 20–70°C were obtained. The EtBr binding constants and the number of binding sites were determined. The thermodynamic parameters of the EtBr intercalation complex upon changes of solution temperature 20–48°C were calculated: 1.0·106 M−1K≤1.4·106 M−1, free energy ΔG o=−8.7±0.3 kcal/mol, enthalpy ΔH o≅0, and entropy ΔS o=28±0.5 cal/(mol deg). UV melting has shown that the melting temperature (T m) of EtBr-poly(dA)poly(dT) complexes (μ=0.022,4.16·10−5 M EtBr) increased by 17°C as compared with the ΔT m of free homopolymer, whereas the half-width of the transition (T m) is not changed. It was shown for the first time that EtBr forms complexes of two types on single-stranded regions of poly(dA)poly(dT) denatured at 70°C: strong (K 1=1.7·105 M−1; ΔG o=−8.10±0.03 kcal/mol) and weak (K 2=2.9·103 M−1; ΔG o=−6.0±0.3 kcal/mol).The ΔG o of the strong and weak complexes was independent of the solution ionic strength, 0.0022≤μ≤0.022. A model of EtBr binding with single-stranded regions of poly(dA)poly(dT) is discussed.  相似文献   

14.
Several scientists collected extensively cyphellaceous Hymenomycetes, Basidiomycota, with cup-shaped fruitbodies for the ‘Flora Neotropica’ project. A distinctive group within these fungi comprises genera with characteristically encrusted, non-ramified hyphae on the outer side of their fruitbodies, called surface hyphae. The genus Flagelloscypha, typically provided with whiplash-like distal ends on these hyphae, is one of the better known genera of this group. Here, we propose F. crassipilata as a new species, which is characterised by (3.5)4–6.5(8) μm thick surface hyphae, by extremely big basidia measuring 36–40(44) × 8.5–10.5 μm, and asymmetrically ovoid to asymmetrically ellipsoid, 10.5–12 × (4.5)5–5.5 μm large spores. Differences to similar species are discussed and a short introduction to genera related to Flagelloscypha is given.  相似文献   

15.
16.
 The effect of phytoplankton size on feeding rates of planktonic larvae of the crown-of-thorns starfish Acanthaster planci (L.) was evaluated by examining their gut contents under an epifluorescence microscope. Concentrations of coccoid cyanobacteria in natural seawater ranged between 1.73 and 5.33×105 cells ml-1 and were three to four orders of magnitude greater than that of eukaryotes. Under these conditions, A. planci larvae ingested similar or smaller numbers of cyanobacteria than eukaryotes. Consequently, clearance rates of A. planci larvae on cyanobacteria were approximately three orders of magnitude lower than those on eukaryotes. Cyanobacteria and eukaryotes in the gut of A. planci larvae had mean equivalent spherical diameters (ESD) of 1–2 μm and 3.6–4.6 μm, respectively. Thus, the volume of cyanobacteria ingested was less than 10% of the volume of eukaryotes ingested. Acanthaster planci larvae were fed cultured phytoplankton Dunaliella tertiolecta and suspensions of three different sizes of plastic beads with fluorescence labelling. There was no significant difference in clearance rates on 6 and 20 μm plastic beads. Clearance rates on 1 μm plastic beads were, however, much lower than those on 6 and 20 μm plastic beads. Clearance rates of A. planci larvae on D. tertiolecta (ca. 5 μm ESD) were significantly higher than those on 6 and 20 μm plastic beads. Apart from particle size, this result shows that feeding of A. planci larvae is influenced by other properties of potential food particles. Accepted: 24 May 1996  相似文献   

17.
G. Zimmermann 《BioControl》1978,23(2):181-187
Zusammenfassung Von pilzbefallenen Larven der KohlschabePlutella maculipennis Curt. wurdeEntomophthora blunckii Lakon exZimmermann isoliert. Die Art wird mit lateinischer Diagnose gültig beschrieben, die morphologischen Merkmale werden erg?nzend angegeben und erstmals durch Fotos belegt.E. blunckii w?chst gut auf koaguliertem Eidotter, weniger gut auf Sabouraud-Glucose-Agar. Mycelwachstum wurde zwischen 8° und 28°C beobachtet, dagegen nicht bei 32°C. Die Symptome infizierter Larven werden geschildert und der Pilz wird mit ?hnlichen Arten verglichen.
Summary Entomophthora blunckii Lakon exZimmermann was isolated from larvae of the diamondback-mothPlutella maculipennis Curt. and redescribed. The fungus is characterized by its elliptical to pear-shaped conidia (from infected larvae 13–20×7–11 μm, mostly 15–18×7–9 μm) with the outer membrane often inflated and its branched conidiophores forming a dense gray to faint greenish-yellowish covering over the body of the insect. The symptoms of larvae infected withE. blunckii are described. The species grows on coagulated egg yolk, less well on Sabouraud-Dextrose-Agar. Growth was observed between 8° and 28°C but not at 32°C. The fungus is compared with similar species.
  相似文献   

18.
Acetate-degrading anaerobic microorganisms in freshwater sediment were quantified by the most probable number technique. From the highest dilutions a methanogenic, a sulfate-reducing, and a nitrate-reducing microorganism were isolated with acetate as substrate. The methanogen (culture AMPB-Zg) was non-motile and rod-shaped with blunted ends (0.5–1 μm × 3–4 μm long). Doubling times with acetate at 30–35°C were 5.6–8.1 days. The methanogen grew only on acetate. Analysis of the 16S rRNA sequence showed that AMPB-Zg is closely related toMethanosaeta concilii. The isolated sulfate-reducing bacterium (strain ASRB-Zg) was rod-shaped with pointed ends (0.5–0.7 μm × 1.5–3.5 μm long), weakly motile, spore forming, and gram positive. At the optimum growth temperature of 30°C the doubling times with acetate were 3.9–5.3 days. The bacterium grew on a range of organic acids, such as acetate, butyrate, fumarate, and benzoate, but did not grow autotrophically with H2, CO2, and sulfate. The closest relative of strain ASRB-Zg isDesulfotomaculum acetoxidans. The nitrate-reducing bacterium (strain ANRB-Zg) was rod-shaped (0.5–0.7 μm × 0.7–1 μm long), weakly motile, and gram negative. Optimum growth with acetate occurred at 20–25°C. The bacterium grew on a range of organic substrates, such as acetate, butyrate, lactate, and glucose, and did grow autotrophically with H2, CO2, and oxygen but not with nitrate. In the presence of acetate and nitrate, thiosulfate was oxidized to sulfate. Phylogenetically, the closest relative of strain ANRB-Zg isVariovorax paradoxus.  相似文献   

19.
This paper describes the morphological characteristics of a new species of Haemogregarina Danilewsky, 1885, from naturally infected Acanthodactylus boskianus (Daudin) in Egypt, based on both blood and tissue stages. The prevalence of infection was found to be 66% (33/50). The blood stages were found to be confined to the erythrocytes and could be differentiated into small and large forms. The small form (trophozoites) measures 8 × 3.5 μm, whereas the large form (mature gamonts) measures 12 × 5 μm. The tissue stages were observed only in the liver. Meronts occurred within parasitophorous vacuoles in hepatocytes and ranged from mononucleate forms to mature forms that contained c.10–15 merozoites.  相似文献   

20.
Cocconeis scutellum var.ornata Grun. from three localities of Japan was studied. The striation density in 10 μm showed a marked tendency to increase with the decrease of the valve length in both raphe and rapheless valves, and this tendency did not vary with locality or environmental condition. The striation densities of rapheless valves were 4–6 in 10 μm for a valve length of 40μm, 4–6.5 for 30 μm, 6–9 for 20μm and 6.5–11 for 15μm. Those of raphe valves were 10–11 in 10μm for a valve length of 40μm, 10–12 for 30μm, 11–14.5 for 20μm and 12.5–17 for 15μm. According to the range of changing value in striation density obtained by the present study,C. scutellum var.schmidti Frenguelli andC. japonica Schmidt are identical withC. scutellum var.ornata. Dedicated to Prof. Munenao Kurogi on the occasion of his academic retirement. Culture experiment in the present study was undertaken at the Institute of Algological Research, Faculty of Science, Hokkaido University at Muroran.  相似文献   

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