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Studies - N°3-Ultrastructure of spermiogenesis and spermatozoa in Mesocastrada
Accession Number 063LN-0001 Document Delivery 063LN: Document Delivery available Authors Culioli JL. Foata J. Mori C. Orsini A. Marchand B. Author e-mail Address jculioli@univ-corse.fr Title Ultrastructure of spermiogenesis and spermatozoa in Mesocastrada fuhrmanni Voltz, 1898 (Platyheiminthes, Rhabdocoela, Typhloplanoida) Source Zoologischer Anzeiger. 245(1):3-12, 2006 Jul. Abbreviated Source Zool. Anz. 245(1):3-12, 2006 Jul. Copyright Publisher ELSEVIER GMBH, URBAN & FISCHER VERLAG, OFFICE JENA, P O BOX 100537, 07705 JENA, GERMANY. URL: http://www.elsevier.com ISSN 0044-5231 Author Keywords Spermiogenesis. Spermatozoon. Ultrastructure. Mesocastrada fuhrmanni. Typhloplanoida. KeyWords Plus Intestinal parasite. Craspedella sp. Platyhelminthes. Cestoda. Cyclophyllidea. Sperm. Plathelminthes. Senegal. Dalyellioida. Turbellaria. Abstract Electron microscopy of the testes of the free-living flatworm Mesocastrada Fuhrmanni collected from temporary freshwater ponds shows stages of spermiogenesis that are like other species of the Typhloplanidae. Spermiogenesis in Mesocastrada fuhrmanni is characterized by the presence, in the spermatid, of a differentiation zone underlain by peripheral microtubules and centered on two centrioles with an intercentriolar body. Two flagella of the 9 + "1" pattern of the Trepaxonemata grow out in opposite directions from the centrioles. The flagella undergo a latero-ventral rotation, and a subsequent disto-proximal rotation of centrioles occurs in the spermatid. The former rotation involves the compression and the detachment of a row of cortical microtubules, and allows us to recognize a ventral from a dorsal side. Two features are of special interest at the end of differentiation: peripheral cortical microtubules lie parallel to the sperm axis near the anterior tip, but microtubules become twisted (about 40 degrees with reference to the gamete axis) near the posterior extremity; in the same way, the posterior tip of the nucleus is spiralled. As far as we know, these features are observed for the first time in the Typhloplanidae. The pattern of spermiogenesis and the ultrastructural organization of the spermatozoon are compared with the available data on Typhloplanoida and in particular, species of the Typhloplanidae family. (c) 2006 Elsevier GmbH. All rights reserved. [References: 40] Language English Publication Type Article Subset Current Contents(R)/Agriculture, Biology & Environmental Sciences. CC Categories Animal Sciences in Current Contents(R)/Agricultural, Biology & Environmental Sciences. Entry Week 2006 week 33 Reprint Address Reprint available from: Culioli JL. Univ Corse, Lab Modeles Ecol Mediterraneenne, Fac Sci & Tech, F-20250 Corte, France, . Institution Reprint available from: Culioli JL Univ Corse, Lab Modeles Ecol Mediterraneenne, Fac Sci & Tech F-20250 Corte France Date de création : 13/02/2007 @ 16:45 Special !
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