Ultrastructure of the spermatozoon of the teleost fish Acanthopagrus schlegeli (Perciformes: Sparidae)

Abstract

Ultrastructurally the spermatozoon of Acanthopagrus schlegeli (Sparidae) has a spherical, homogeneously electron-dense nucleus with a deep axial nuclear fossa, and an unusual notch, shaped like a bowtie, in the nuclear region. The short midpiece contains four spherical mitochondria and encircles the basal body of the flagellum. It is concluded that the spermatozoon is of a primitive type, although it is characterized by several unique features which may provide useful systematic characters. © 1993 Wiley-Liss, Inc.

Biflagellate spermatozoon structure of the hermaphrodite fish Satanoperca jurupari (Heckel, 1840) (Teleostei, Cichlidae) from the Amazon River

“…Although they belong to the primitive type they show some unusual features. To date all the fish spermatozoa examined show some structural homogeneity which supports the idea that the ultrastructural features of spermatozoon can be useful for taxonomic and phylogenetic studies (Baccetti et al, 1984;Mattei, 1991;Mattei & Mattei, 1984;Gwo et al, 1993Gwo et al, , 1996.…”

“…Examination of other cichlids will be necessary to determine whether the primitive features of S. jurupari spermatozoa are common to this family (Mattei, 1991). This investigations will also furnish the information needed for determining the phylogenetic position to the Cichlids on the basis of spermatozoan structure which is known to be a valuable indicator of phylogenetic relationships in numerous groups (Mattei, 1991;Jamieson, 1991;Gwo et al, 1993).…”

“…On the other hand, the presence of the two lateral cytoplasmic extensions (or ribbons) in opposite insertion on each flagellum has been described in few teleost species (Billard, 1970) as well as in other fish groups (Mattei, 1970;Matos & Azevedo, 1989). Despite a well and detailed date on spermatogenesis, the majority of teleost spermatozoa remains unexamined lacking data to allow the establishment of phylogenetic relationships amongst the teleost fishes (Mattei, 1991;Gwo et al, 1993).…”

The sperm ultrastructure of Merluccius merluccius (Teleostei, Gadiformes): phylogenetic considerations

“…Other structures associated with the basal body and axoneme, such as the lateral plate and the Y‐shaped bridges, are of widespread occurrence in teleosteans, in both spermatozoa type I and type II (Eiras‐Stofella et al . 1993; Gwo et al . 1993, 1994; Gwo 1995; Lahnsteiner and Patzner 1997; Hara and Okiyama 1998; Abascal et al .…”

“…In the spermatozoon of A. calva the centrioles remain at a considerable distance from the nucleus and close to the cell surface; consequently, the associated plasma membrane is not drawn towards the nucleus and into the sperm midpiece, and therefore a cytoplasmic canal does not form in this species. Other structures associated with the basal body and axoneme, such as the lateral plate and the Y-shaped bridges, are of widespread occurrence in teleosteans, in both spermatozoa type I and type II (Eiras-Stofella et al 1993;Gwo et al 1993Gwo et al , 1994Gwo 1995;Lahnsteiner and Patzner 1997;Hara and Okiyama 1998;Abascal et al 2002), hence these elements are of limited use in phylogenetic analyses.…”