English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/63924
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Embryo development of Corticium candelabrum (Demospongiae : Homosclerophorida)

AuthorsDe Caralt, S. ; Uriz, María Jesús ; Ereskovsky, Alexander V.; Wijffels, R. H.
Issue Date2007
CitationInvertebrate Biology 126 (3) : 211-219 (2007)
AbstractCorticium candelabrum is a homosclerophorid sponge widespread along the rocky Mediterranean sublittoral. Scanning and transmission electron microscopy were used to describe the gametes and larval development. The species is hermaphroditic. Oocytes and spermatocytes are clearly differentiated in April. Embryos develop from June to July when the larvae are released spontaneously. Spermatic cysts originate from choanocyte chambers and spermatogonia from choanocytes by choanocyte mitosis. Oocytes have a nucleolate nucleus and a cytoplasm filled with yolk granules and some lipids. Embryos are surrounded by firmly interlaced follicular cells from the parental tissue. A thin collagen layer lies below the follicular cells. The blastocoel is formed by migration of blastomeres to the morula periphery. Collagen is spread through the whole blastocoel in the embryo, but is organized in a dense layer (basal lamina) separating cells from the blastocoel in the larva. The larva is a typical cinctoblastula. The pseudostratified larval epithelium is formed by ciliated cells. The basal zone of the ciliated cells contains lipid inclusions and some yolk granules; the intermediate zone is occupied by the nucleus; and the apical zone contains abundant electron-lucent vesicles and gives rise to cilia with a single cross-striated rootlet. Numerous paracrystalline structures are contained in vacuoles within both apical and basal zones of the ciliated cells. Several slightly differentiated cell types are present in different parts of the larva. Most cells are ciliated, and show ultrastructural particularities depending on their location in the larvae (antero-lateral, intermediate, and posterior regions). A few smaller cells are non-ciliated. Several features of the C. candelabrum larva seem to support the previously proposed paraphyletic position of homoscleromorphs with respect to the other demosponges.
Description9 páginas, 26 figuras.
Publisher version (URL)http://dx.doi.org/10.1111/j.1744-7410.2007.00091.x
Appears in Collections:(CEAB) Artículos
Files in This Item:
File Description SizeFormat 
accesoRestringido.pdf15,38 kBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.