Results 101 to 110 of about 311 (131)

Structure of the choanocyte kinetid in the sponge Haliclona sp. (Demospongiae: Haplosclerida) and its implication for taxonomy and phylogeny of Demospongiae

Biology Bulletin, 2016
Sponges are a group of primitive animals that are of particular interest in terms of evolutionary theory. Molecular and phylogenic studies have revealed the common origin of sponges and Metazoa and the relationship of Metazoa to Choanoflagellata. Comparative studies of the morphology have allowed reconstruction of the structure of ancestors common to ...
I. R. Pozdnyakov, S. A. Karpov
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The spermatogenesis ofHalichondria panicea (Porifera, Demospongiae)

Zoomorphology, 1990
Spermatogenesis of the marine spongeHalichondria panicea begins with the break up of choanocyte chambers, choanocytes constituting the origin of spermatogonia. The transition from choanocytes to spermatogonia is direct, without cell division. Already the spermatogonia are flagellated.
Dagmar Barthel, Andrea Detmer
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North coast of Brazil (Demospongiae, Poecilosclerida)

2004
Mothes, Beatriz, De, Maurício A., Campos (2004): North coast of Brazil (Demospongiae, Poecilosclerida).
Mothes, Beatriz, De, Maurício A., Campos   +2 more
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Sexual reproduction ofCinachyra tarentina(porifera, demospongiae)

Italian Journal of Zoology, 2000
Abstract The sexual reproductive cycle of the Tetractinomorpha Spirophorida Cinachyra tarentina was studied mainly using light microscopy on samples collected in South Italy over a 2‐year period. Some aspects of the egg morphology were observed using transmission electron microscopy.
Lepore E., Sciscioli M., Scalera Liaci L., Santarelli G., GAINO, Elda Rosa   +4 more
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Choanocyte ultrastructure in Halisarca dujardini (Demospongiae, Halisarcida)

Journal of Morphology, 2008
AbstractUnderstanding poriferan choanocyte ultrastructure is crucial if we are to unravel the steps of a putative evolutionary transition between choanoflagellate protists and early metazoans. Surprisingly, some aspects of choanocyte cytology still remain little investigated.
Elisaveta, Gonobobleva, Manuel, Maldonado   +1 more
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New Species of Lissodendoryx Topsent, 1892 (Demospongiae, Poecilosclerida, Coelosphaeridae) and Myxilla Schmidt, 1862 (Demospongiae, Poecilosclerida, Myxillidae) from the Northeast Pacific

Zootaxa, 2019
Collections of sponges by the late Dr. William C. Austin and the authors (N. McDaniel, R. Harbo and B. Ott) provided material for descriptions of new species from two genera of Poecilosclerida for shallow waters of Southern British Columbia, Canada and Northern Washington, USA: Lissodendoryx and Myxilla.
B, Ott, H M, Reiswig, N, McDANIEL, R, Harbo   +3 more
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Ultrastructural study of spermatogenesis inOscarella lobularis(Porifera, Demospongiae)

International Journal of Invertebrate Reproduction and Development, 1986
Summary The various phases of spermatogenesis in the demosponge Oscarella lobularis were studied by electron microscopy. Spermatogenesis occurs within spermatic cysts, which are presumed to derive from choanocyte chambers by transformation of choanocytes into spermatogonia. Germ cells develop asynchronously within spermatocysts, and cytoplasmic bridges,
Gaino E., BURLANDO, Bruno Pietro, Buffa P., Sarà M.   +3 more
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In situ pumping activities of tropical Demospongiae

Marine Biology, 1971
Studies employing Scuba techniques were carried out on populations of 3 species of tropical demosponges to determine in situ patterns of water-pumping activity. Short-term changes in individual activity of deep-water species (15 to 55 m) were determined from continuous recordings of exhalant current velocities.
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The cytology of a Haliclona oculata (Demospongiae, Haplosclerida) /

1985
This item was digitized as part of a project to share McGill's intellectual legacy with the public. If you are the copyright holder or a relative of the copyright holder who is deceased, you may request withdrawal by emailing escholarship.library@mcgill.ca.
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Taxonomy and phylogeny of the family Suberitidae (Porifera: Demospongiae) in California

Zootaxa
Abstract This study presents a comprehensive taxonomic revision of the family Suberitidae (Porifera: Demospongiae) for California, USA. We include the three species previously known from the region, document two additional species previously known from other regions, and formally describe four new species as
THOMAS L. TURNER, GREG W. ROUSE, BROOKE L. WEIGEL, CARLY JANUSSON, MATTHEW A. LEMAY, ROBERT W. THACKER   +5 more
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