Results 161 to 170 of about 938 (210)

Influence of small river conditions on the abundance of Tubificidae

Hydrobiologia, 1994
Two small rivers, the Yerik and Nezhegolyok, were studied seasonally in 1979–1980. Increase in concentration of nitrogen and phosphorus compounds in the river water as well as proliferation of enterococci and enterobacilli favoured the abundance of Tubificidae while, at the same time, their numbers were reduced by chironomids and leeches.
exaly   +2 more sources

Phylogeny of Tubificidae (Annelida, Clitellata) based on mitochondrial and nuclear sequence data

Molecular Phylogenetics and Evolution, 2005
The tubificid clitellates are a common component in the freshwater bottom fauna and are also the most abundant oligochaete group in marine habitats.
Christer Erséus, Mari Källersjö
exaly   +2 more sources

Marine species of Ainudrilus and Heterodrilus (Oligochaeta: Tubificidae: Rhyacodrilinae) from Hainan Island in southern China

New Zealand Journal of Marine and Freshwater Research, 2003
Six species of Rhyacodrilinae (Oligochaeta: Tubificidae) are reported from intertidal and shallow water subtidal habitats around Hainan Island in southern China. Four species are new to science: Ainudrilus pauciseta n. sp., Heterodrilus chenianus n. sp.,
Hongzhu Wang, Christer Erséus
exaly   +1 more source

Parthenogenesis in Tubificidae

Hydrobiologia, 1984
The ability of tubificids to reproduce parthenogenetically following or in place of bisexual reproduction has been proved. During parthenogenesis the spermatogenesis ceases at an early stage of sexual cell development, which, together with some peculiarities of the structure of the sexual system, rules out the possibility of self-fertilization in the ...
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Aspects of the phylogeny of the marine Tubificidae

Hydrobiologia, 1984
A tentative phylogeny of the oligochaete family Tubificidae, with emphasis on the marine representatives, is presented. The scheme is based on the morphology and arrangements of prostate glands and the setal patterns. The rhyacodriline, more or less diffuse prostates are regarded as a primitive stage in prostate evolution, preceded only by the ...
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An ultrastructural study of microtubules and the acrosome in spermiogenesis of tubificidae (oligochaeta)

Journal of Ultrastructure Research, 1979
Limnodriloides winckelmanni shows stages in condensation of the nucleus and development of microtubules in the maturing spermatid similar to those formerly described for Limnodrilus and Tubifex. Contrary to previous reports, the total number of perinuclear and cytoplasmic microtubules does not appear constant. The midpiece in the tubificids, consisting
Jamieson B.G.M., Daddow L.
openaire   +4 more sources

Observations on the biology of the Tubificidae (Oligochaeta)

SIL Proceedings, 1922-2010, 1964
(1964). Observations on the biology of the Tubificidae (Oligochaeta) SIL Proceedings, 1922-2010: Vol. 15, No. 2, pp. 855-863.
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Enzymatic variability in sympatric species of Tubifex (Clitellata: Tubificidae)

Hydrobiologia, 1999
The globally distributed species Tubifex tubifex Muller, 1774 (Clitellata; Tubificidae) is sometimes considered to include several different morphological forms, each recognizable by their chaetal structure. The ‘blanchardi’ form is a distinct species: sympatric populations of Tubifex tubifex and Tubifex blanchardi Vejdovsky, 1871 show complete ...
Di Chiara, AP, Pagani, M, LEONI, BARBARA
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The double sperm line in Isochaetides (Annelida, Clitellata, Tubificidae)

Tissue and Cell, 2002
Sperm morphology and spermatogenesis were examined in the oligochaete annelid Isochaetides arenarius, a species belonging to the subfamily Tubificinae inhabiting the sediments of Lake Baikal. As all tubificines, Isochaetides produces two types of spermatozoa, named eusperm and parasperm.
M. Ferraguti, R. Marotta, P. Martin
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Development of the genital ducts in Telmatodrilinae (Tubificidae, Clitellata)

Journal of Morphology, 2004
AbstractIn Tubificidae, the male genital duct comprises a funnel in the testes segment, followed by a vas deferens, an atrium, and, frequently, a copulatory structure in the adjacent ovarian segment. There may also be a diffuse or compact prostate gland in association with the duct. The morphology and position of the genital ducts are important for the
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