Spermiogenesis and sperm ultrastructure of Carmyerius endopapillatus (Digenea, Gastrothylacidae), a parasite of Bos taurus in Senegal

Abstract

Ultrastructural study of spermiogenesis and of the spermatozoon of Carmyerius endopapillatus has enabled to describe some characteristics of this digenea. The intercentriolar body situated between the two striated roots and the two centrioles, presents a symmetric organization. Both external bands of this intercentriolar body are made up of a row of granules. During spermiogenesis, a flagellar rotation of 90° is described. The old spermatid does not present external ornamentations. The spermatozoon is characterized, in its anterior region, by the presence of a lateral expansion exhibiting one spinelike body. In C. endopapillatus, external ornamentations are localized only at the level where the lateral expansion appears. The posterior extremity of spermatozoon exhibits a nucleus surrounded by a plasmic membrane lacking microtubules, but presenting a small lateral expansion. This is the first species of Gastrothylacidae family studied by transmission electron microscopy.

Spermiogenesis and sperm ultrastructure of Cotylophoron cotylophorum (Trematoda, Digenea, Paramphistomidae), a parasite of Bos taurus in Senegal

“…The posterior extremity of the C. cotylophorum mature spermatozoon contains a nucleus surrounded by a plasmic membrane, without cortical microtubules, but presenting a small lateral expansion. A posterior extremity with such a lateral process has been previously described in Carmyerius endopapillatus (Seck et al 2008) and Bucephaloïdes gracilenscens (Erwin and Halton 1983). But in this last species, the posterior extremity contains in addition, an axoneme and cortical microtubules.…”

“…The external bands are made up of a line of granules, and not of a continuous band as it is the case in the majority of the trematodes. Today, such an intercentriolar body has only been observed in Ceylonocotyle scoliocoelium (Li and Wang 1997), Troglotrema acutum (Miquel et al 2006), Paramphistomum microbothrium (Seck et al 2007), and Carmyerius endopapillatus (Seck et al 2008). In other trematodes, the intercentriolar body is Levron et al (2004b) composed of nine electron-dense bands.…”

Sperm ultrastructure of the gall bladder fluke Anisocoelium capitellatum (Digenea: Cryptogonimidae), a parasite of Uranoscopus scaber (Pisces: Uranoscopidae)

“…The flagellum is the most common ultrastructural element remaining in the posterior extremity of the spermatozoon (e.g., Jamieson and Daddow 1982;Stitt and Fairweather 1990;Cifrian et al 1993;Ndiaye et al 2003a;Miquel et al 2006;Quilichini et al 2007b) even if some species exhibit cortical microtubules (Quilichini et al 2007a, d), glycogen granules (Miquel et al 2000;Levron et al 2003Levron et al , 2004c, nucleus (Ndiaye et al 2004;Ashour et al 2007), or nucleus in association with different elements (Iomini and Justine 1997;Gracenea et al 2000; Levron et al Seck et al 2008b). Among the posterior extremity with one flagellum, some distal extremities of the axoneme have been described.…”

“…These membrane ornamentations are considered as an enigmatic structure of digeneans spermatozoon (Justine 1999) and constitute an interesting criterion for the phylogeny (Justine 1995). This ultrastructural feature is common in Digenean species as for example in Pseudorhipidocotyle elpichthys (Tang et al 1998), Opecoeloides furcatus (Miquel et al 2000), Scaphiostomum palaearcticum (Ndiaye et al 2002), M. parvus (Levron et al 2004a), or Carmyerius endopapillatus (Seck et al 2008b). Their localization along the spermatozoon varies according to the species.…”

Spermatological characters of the aspidogastrean Aspidogaster limacoides Diesing, 1835

“…In Digenea, a small lateral expansion has been reported in the mature spermatozoon of some species (Levron et al 2004;Ndiaye et al 2004;Seck et al 2008). However, due to the small size, this expansion cannot be compared with the long undulating membrane observed in Aspidogastrea.…”