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1.
Soetaert  K.  Vincx  M. 《Hydrobiologia》1988,164(1):33-38
Spirobolbolaimus bathyalis gen. nov., sp. nov. is described from the continental slope off Calvi (Mediterranean). The new genus Spirobolbolaimus belongs to the Microlaimidae Micoletzky, 1922 and is closely related to the genus Bolbolaimus Cobb, 1920. It can be differentiated from Bolbolaimus by its multispiral amphideal fovea and by its six rows of postamphideal setae.  相似文献   

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A new species of Arenopontia (Neoleptastacus) is described on the basis of a single female collected from one sandy beach in Montenegro, Adriatic Sea. With the addition of the new species, the subgenus Neoleptastacus now includes 18 species throughout the world. At the end of this paper there is a key for their determination. Received: 20 March 1999 / Received in revised form: 15 September 1999 / Accepted: 21 September 1999  相似文献   

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Nine specimens of Apus affinis (J.E. Gray) were studied at Franceville, Haut-Ogooué Province, Republic of Gabon, for the presence of helminth parasites. Two cestode species of the family Dilepididae were recorded. Pseudangularia gonzalezi n. sp. is distinguished from the most similar species P. europaea Georgiev & Murai, 1993 by having elliptical cirrus-sac, longer vagina, longer rostellar sheath and greater diameter of suckers. An identification key to the species of the genus Pseudangularia Burt, 1938 is proposed. The present study is the first record of the genus Pseudangularia in the Afrotropical Region. Our study confirms that, in dilepidids with vaginal sclerites from swifts, breaking off the cirrus after copulation is a frequent phenomenon. The genus Gibsonilepis n. g. is erected as monotypic for Vitta swifti Singh, 1952 (originally described from the same host species in India) and Gibsonilepis swifti n. comb. is proposed. Gibsonilepis n. g. is distinguished from Vitta Burt, 1938 by its highly elongate rostellum, rostellar sheath much bigger than rostellum, relatively small rostellar hooks possessing strongly developed guard, disc-shaped suckers with weak peripheral musculature and flat or convex central part, long and well-expressed neck, highly lobed two-winged ovary (lobes rounded) and presence of a band consisting of rows of spine-like microtriches along posterior margin of each proglottis. This is the first record of G. swifti in the Afrotropical Region. The separation of G. swifti from the genus Vitta (parasites of swallows) suggests that, contrary to previous opinions, no dilepidid genera are shared by Apodidae (swifts) and Hirundinidae (swallows).  相似文献   

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Arctodiaptomus (Rhabdodiaptomus) michaeli n.sp. is described from the material collected in Alapathar Lake and Marsar Lake of Kashmir, India.  相似文献   

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Taeniarhynchaena gen. n. differs from other genera in its long, cylindrical, proboscidiform rostellum that can be withdrawn and coiled within the rostellar sac. The distal end of the rostellum is expanded and bifid forming two lobes each bearing wrench-shaped hooks peripherally. Other generic characters are the regular alternation of genital apertures, genital ducts dorsal to excretory vessels, testes restricted to posterior moiety of the proglottis, and a persistent uterus. Type species: Taeniarhynchaena micropalamae gen. et sp. n. from the stilt sandpiper Micropalama himantopus (Bonaparte, 1826) taken near Churchill on Hudson Bay, Canada. It is 1.5 to 2.9 mm long with 11 to 16 proglottides. The rostellum 0.45 to 0.5 long and 0.023 to 0.036 mm in diameter has five hooks 0.023 mm long on each lobe. Testes 14 in posterior two-fifths of the proglottis.  相似文献   

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A new unicellular species of the genusChrysosphaerella (Chrysophyceae) was found in fresh-water ponds in Switzerland, Japan, and the U.S.A. It is described asC. solitaria. The genus is divided into two subgenera:Chrysosphaerella, comprising the colonial species, andPseudochrysosphaerella, the unicellular ones.  相似文献   

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Salema Sarpa salpa (Linnaeus, 1758), were caught in the middle-eastern Adriatic Sea from August to November 2004. Length range of the samples was between 10.3 and 43.9 cm, with mean values of 25.5 cm in males, 32.6 cm in females, and 11.4 and 20.2cm in immature and hermaphrodite specimens, respectively. Sex ratio (males : females) was 3.1 : 1. Males were observed up to 37 cm length. Hermaphrodites showed lengths between 18 and 21 cm. The species was characterized by protandric hermaphroditism. Size at sexual maturity was 20.6 cm (2 years old) for males. Total length-total weight relationship for the entire population is described by the parameters a  = 0.00893, and b  = 3.1055. Otolith age readings showed that the population consisted of 15 age groups (1–15 years), including a very high proportion of individuals 1–7 years old. The von Bertalanffy growth parameters were L  = 33.11cm, k  = 0.514, and t 0 = −0.392 years for males and L  = 40.85cm, k  = 0.179, and t 0 = −2.606 years for females. Survival rate of females ( S  = 0.870) was much greater than for males ( S  = 0.769).  相似文献   

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Pararalichus gen.n. (Pterolichidae, Pterolichinae) is described; two species groups, from species of Brotogeris Vigors and Touit Gray, respectively, include two named and ten new species. From Brotogeris : the type species Pararalichus dilatatus (Favette & Trouessart) stat.n., comb.n. [= Protolichus ( Mesolichus ) hemiphyllus dilatatus ] from Brotogeris jugularis (Müller), Brazil, Guatemala, Panama; P. chrysopteri sp.n. from B. chrysopterus (L.). Guyana, Surinam; P. cyanopterae sp.n. from B. cyanoptera (Pelzeln), Bolivia, Peru; P. pyrrhopteri sp.n. from B. Pyrrhopterus (Latham), Ecuador, Peru; P. sanctithomae sp.n. from B. sanctithomae (Müller), Bolivia, Peru; P. tiricae sp.n. from B. tirica (Gmelin), Brazil; P. versicolori sp.n. from B. versicolorus (Müller), Brazil, Peru. From Touit: P. hemiphyllus (Mégnin & Trouessart) comb.n. [ =Pterolichus (P.) hemiphyllus ] from Touit batavica (Boddaert), Surinam, Trinidad; P. dilectissimae sp.n. thrn T. dilectissima (Sclater & Salvin), Colmbia, Costa Rica; P. huetii sp.n. from T. huetii (Temminck), Brazil, Guyana, Peru; P. parpuratae sp.n. from T. purpurata (Gmelin), Brazil, Guyana, Surinam; P. surdae sp.n. from T. surda (Kuhl), Brazil. All hosts are Central and South American parrots. Mesolichus Trouessart, 1899 is recognized as a monotypical genus.  相似文献   

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A proboscidean skull from Cheparawa, (Muruyur Formation, Kenya), differs markedly from those of Eurasian Choerolophodon (C. pentelici, C. dhokpathanensis). It is morphologically and metrically close to the holotype of Choerolophodon kisumuensis (MacInnes) a partial skull from Maboko, much of which has been reconstructed in plaster of Paris. The more complete remains of this species now available indicate that it should be placed in a genus separate from Choerolophodon. The new genus Afrochoerodon is erected for it. Choerolophodon ngorora from Ngorora and Fort Ternan (Kenya), Choerolophodon zaltaniensis from Gebel Zelten (Libya) and Choerolophodon chioticus from Chios, Greece, should be transferred to the genus Afrochoerodon. Late Miocene specimens from Nakali, Kenya are probably referrable to the genus Choerolophodon. Fossils from Burji-Soyama (Ethiopia) hitherto assigned to Choerolophodon sp. are excluded from the subfamily Choerolophodontinae.  相似文献   

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Zusammenfassung Bei den Vertretern einiger Diplopoden-Familien ist der Mitteldarm von einer zelligen Hüllschicht umgeben. Die Perikaryen stehen dicht bei dicht, basale Ausläufer durchziehen die Fasern der Muskularis und verzweigen sich sekundär beim Eintritt in die sehr dicke Basallamina des Mitteldarmepithels. Die terminalen Endigungen jeder Zelle dringen in ein extrazelluläres basales Labyrinth je einer ausdifferenzierten Mitteldarmzelle ein und verflechten so die Hüllschicht mit dem Darmepithel. Darüberhinaus scheint es Fusome zwischen den Endaufzweigungen und der Mitteldarmzelle und damit die Möglichkeit eines intrazellulären Stofftransports zwischen beiden Zellen zu geben.Die Hüllschicht ist kein Epithel, denn Zellkontakte zwischen benachbarten Zellen fehlen ebenso wie eine gemeinsame Basallamina. jede Zelle ist von ihrer eigenen, dünnen Basallamina umgeben. Sie wird außerdem bei normal ernährten Individuen durch einen großen Vorrat an Glykogen und zahlreiche Zytosomen charakterisiert. Viele Mitochondrien sind dadurch vor allem in die Zellperipherie oder in die basalen Ausläufer gedrängt. In deren Nähe findet man auch überwiegend glattes endoplasmatisches Retikulum, und auch freie Ribosomen sind nicht selten. Der Zellkern vermittelt den Eindruck hoher Stoffwechselaktivität; ein Nukleolus ist immer vorhanden. Mikrotubuli sind im Zellkortex parallel zur Oberfläche orientiert, vor allem aber in den basalen Ausläufern in Längsrichtung. Obwohl kein Fett gespeichert wird, kann man die Zellen mit dem Chloragog-Gewebe der Anneliden oder mit den Leberzellen der Vertebraten vergleichen. Sie scheinen von den Mitteldarmzellen Nährstoffe zu übernehmen, diese zu verarbeiten, die Produkte freizusetzen oder zu speichern und dabei wertlose stickstoffhaltige Moleküle in den Zytosomen abzulagern. Der gebräuchliche Terminus Leberzellen ist daher angebracht.Tiere, die 14 Tage ohne Nahrung gehalten wurden, zeigen eine erhebliche Schrumpfung der Leberzellen. Deren Plasmalemm ist nur an einigen Stellen mit der Basallamina verbunden, überall sonst ist der extrazelluläre Raum zwischen Zellmembran und Basallamina stark erweitert. Das Glykogen ist größtenteils abgebaut. Der elektronenoptische Kontrast der verschiedenen Zellelemente ist äußerst schwach. Die Mikrotubuli sind völlig verschwunden. Nur die Zytosomen heben sich weiterhin deutlich ab. Aber auch sie scheinen umgewandelt und zu wenigen Ansammlungen zusammengeflossen zu sein. Dies deutet auf Mobilisierung des gespeicherten Glykogens hin, kann aber auch beginnende Degeneration der Leberzellen signalisieren.
Fine structure of the liver cells ofOxidus gracilis (C.L. Koch, 1847) (Diplopoda, Paradoxosomatidae)
Summary In some families of Diplopods the midgut is surrounded by an enveloping cell layer. Basal runners of their pericarya get through the longitudinal and transversal muscle fibres and ramify secundarily before entering the very thick basement membrane of the midgut epithelium. The terminal branches of each cell enter into a basal labyrinth of only one differentiated midgut cell interlacing intensively with the epithelium in this way. Moreover it seems that there are open junctions (fursomes) between terminal branches and the midgut cell and therefore an intracellular transport of materials.The enveloping layer is no epithelium. THere are no typical contacts between neighbouring cells; each enveloping cell is surrounded by its own thin basement membrane, a common basement membrane does not exist. Enveloping cells of normally nourished individuals are characterized by a large storage of glycogene in the cytoplasm. Besides this there are many distinct cytosomes which point at a significant activity in metabolism. Many mitochondria, which mostly pushed off towards the cell periphery or lie in the primarily ramifications indicate the same. Close by there is also prevailing smooth endoplasmic reticulum. Free ribosomes are not rare. The nucleus gives the impression of activity in metabolism too; a nucleolus does exist. Microtubules arranged parallely to the cell surface in the cortex, but especially in the basal ramifications in longitudinal direction can be seen. Though lipoids are not being stored, one might compare these cells with the chloragog tissue in annelids or with the liver cells in vertebrates. They seem to accept food from the midgut cells, to digest and release, respectively store it temporarily, depositing at that valueless nitrogene containing molecules into the cytosomes. The usual term liver cell therefore is wellchosen.Animals after 14 days without food signify a large shrinkage of the liver cells. Plasmalemma is fixed only at certain points to the basement membrane; the extracellular space between them is widened extremely. Glycogene mostly is removed. The electron microscopically visible contrast of the cell elements is very faint. Microtubules have disappeared. Cytosomes, however, contrast distinctly. But they, too, seem to be transformed and joined into a few accumulations. This points to mobilization of the stored glycogene, but in the same manner also to symptomes of degeneration brought into action.


Herrn Professor Dr. Dr. h.c. W.E. Ankel zu seinem 80. Geburtstag am 7.8.1977 gewidmet  相似文献   

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Catadiscus pomaceae sp. n. from the intestine of the prosobranch mollusc Pomacea canaliculata (Lamarck, 1801), is described. The host snail was collected from a lenitic biotope belonging to the Riachuelo basin (Corrientes province, Argentina) during 1985-1986. So far the species of the genus Catadiscus Cohn, 1904 have been recorded in amphibians and reptiles. This is the first instance of a species of that genus parasitizing a mollusc.  相似文献   

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