Results 161 to 170 of about 1,130 (206)

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.
openaire   +1 more source

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 ...
openaire   +1 more source

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
openaire   +2 more sources

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
openaire   +2 more sources

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
openaire   +2 more sources

Studies on the effect of environmental factors on growth of tubificidae

2011 International Conference on Remote Sensing, Environment and Transportation Engineering, 2011
The effect of environmental factors such as life styles pH and DO and temperature on the growth of tubificidae were discussed base on L. hoffmeisteri. The experimental results indicated that attached growth system is superior than suspension growth system for Tubificidae. The average growth rate was 0.466 g.g−1 and −0.242 g.g−1 respectively after three
Juqing Lou, Maoxin Guo, null Meimei Chen
openaire   +1 more source

Cuticular ultrastructure in some marine oligochaetes (Tubificidae)

Invertebrate Biology, 2000
Abstract. The ultrastructure of the thin, non‐cellular cuticle is described for 6 marine oligochaetes, representing 3 of the subfamilies (Phallodrilinae, Limnodriloidinae, and Rhyacodrilinae) of the Tubificidae. The main components of the cuticle in these 6 species, as in most other oligochaetes examined, are: (1) a fiber zone closest to the epidermis,
Lena M. Gustavsson, Christer Erséus
openaire   +1 more source

A generic revision of the Phallodrilinae (Oligochaeta, Tubificidae)

Zoologica Scripta, 1992
The generic classification of the subfamily Phallodrilinae (with a total of 252 species) is revised according to phylogenetic principles. Morphological character patterns are assessed under the principle of maximum parsimony, but due to the poor resolution and instability in the resulting cladograms, the analysis is supplemented with intuitive ...
openaire   +1 more source

The Production Biology of the Tubificidae (Oligochaeta)

1980
Few estimates of production of aquatic oligochaetes have been made. Those that have vary considerably in methodology, the units employed, the values obtained where these can be compared, and sometimes in the concept of production used. Laboratory studies on pure populations may be unreliable.
openaire   +1 more source