Folia Parasitologica 48[3] 209-216 (2001) | DOI: 10.14411/fp.2001.034

Ultrastructure of spermiogenesis and spermatozoa of Discocotyle sagittata (Monogenea: Polyopisthocotylea: Discocotylinea)

Joanne Cable1,2, Richard C. Tinsley1
1 School of Biological Sciences, University of Bristol, Woodland Rd., Bristol BS8 1UG, UK
2 Present address: School of Biosciences, Main Building, Cardiff University, Cardiff CF10 3TL, UK

Ultrastructural analysis revealed that the spermatozoon of Discocotyle sagittata (Leuckart, 1842) is composed of two parallel axonemes, mitochondrion, nucleus and cortical microtubules. The nucleus, which occupies a central/distal position and has an unusual crescent-shaped profile, is slightly shorter than the mitochondrial rod. The two axonemes, which are of unequal length, and the cortical microtubules (up to 68 forming a continuous ring in the principal region) extend almost the entire length of the spermatozoon. A fold of the plasma membrane creates a unilateral flange or undulating membrane. Epifluorescence microscopy indicated that spermatogenesis gives rise to clusters of 64 spermatids connected to a common cytophore. Spermiogenesis and the structure of the filiform sperm of D. sagittata conform to the typical polyopisthocotylean pattern.

Keywords: Platyhelminthes, TEM, fluorescent nuclear labelling, spermatogenesis, spermatozoon

Received: January 19, 2001; Accepted: March 29, 2001; Published: September 1, 2001  Show citation

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Cable, J., & Tinsley, R.C. (2001). Ultrastructure of spermiogenesis and spermatozoa of Discocotyle sagittata (Monogenea: Polyopisthocotylea: Discocotylinea). Folia Parasitologica, 48(3), 209-216. doi: 10.14411/fp.2001.034
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