Mesocestoides lineatus (Goeze, 1782) (Mesocestoididae): new data on sperm ultrastructure.
Spermiogenesis and the ultrastructural characters of the spermatozoon of Mesocestoides lineatus are described by means of transmission electron microscopy, including cytochemical analysis for glycogen. Materials were obtained from a golden hamster (Mesocricetus auratus) after experimental infection with tetrathyridia metacestodes obtained from naturally infected lizards (Anolis carolinensis) from Louisiana. Spermiogenesis in M. lineatus is characterized by the orthogonal growth of a free flagellum, a flagellar rotation, and a proximodistal fusion. The zone of differentiation contains 2 centrioles associated with striated rootlets and a reduced intercentriolar body. The mature spermatozoon of M. lineatus lacks a mitochondrion, and it is characterized by the presence of (1) a single, spiraled, crested body 150 nm thick; (2) a single axoneme of the 9+'1' pattern of trepaxonematan Platyhelminthes; (3) a parallel and reduced row of submembranous cortical microtubules; (4) a spiraled cordon of glycogen granules; and (5) a spiraled nucleus encircling the axoneme.
Miquel
Jordi
J
Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, sn, 08028 Barcelona, Spain. jordimiquel@ub.edu
Eira
Catarina
C
Swiderski
Zdzisław
Z
Conn
David Bruce
DB
D000818:Animals; D002590:Cestode Infections / Q000469:parasitology / Q000662:veterinary; D006224:Cricetinae; D008116:Lizards / Q000469:parasitology*; D008297:Male; D008645:Mesocestoides / Q000502:physiology / Q000648:ultrastructure*; D008647:Mesocricetus; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D013091:Spermatogenesis; D013094:Spermatozoa / Q000648:ultrastructure*