Comparative description and discussion of spermiogenesis and spermatozoal ultrastructure in some species of Heptapteridae and Pseudopimelodidae (Teleostei: Siluriformes)

Abstract

The data obtained in the present study on spermiogenesis and spermatozoal ultrastructure of Pseudopimelodidae and Heptapteridae show that they share some characteristics, but greatly differ from each other. The main differences are the occurrence of type I spermiogenesis in Pseudopimelodidae and type III in Heptapteridae, the presence of nuclear fossa in Pseudopimelodidae and its absence in Heptapteridae, the presence of long midpiece in Pseudopimelodidae and short midpiece in Heptapteridae, the presence of cytoplasmic canal in Pseudopimelodidae and its absence in Heptapteridae, the presence of many large vesicles in the midpiece of Pseudopimelodidae and the presence of very long vesicles placed in the peripheral distal region in Heptapteridae, and mitochondria distributed all over the midpiece in Pseudopimelodidae, and very close to the nucleus in Heptapteridae. Heptapteridae and Pimelodidae share several characteristics, such as type III spermiogenesis, a similar chromatin condensation pattern, and the absence of nuclear fossa and flagellar lateral fins. The spermatozoa of Pseudopimelodidae is more similar to those of Siluridae. However, the absence of additional data on spermiogenesis and spermatozoa in siluriforms still limits a broader discussion in the order.<br>Os dados obtidos no presente estudo sobre a ultraestrutura da espermiogênese e dos espermatozóides de Pseudopimelodidae e Heptapteridae mostram que eles compartilham algumas características, mas são bastante diferentes uns dos outros. As principais diferenças são a ocorrência de espermiogênese do tipo I em Pseudopimelodidae e do tipo III em Heptapteridae, a presença de fossa nuclear em Pseudopimelodidae e sua ausência em Heptapteridae, a presença de uma peça intermediária longa em Pseudopimelodidae e uma peça intermediária curta em Heptapteridae, a presença de um canal citoplasmático em Pseudopimelodidae e sua ausência em Heptapteridae, a presença de muitas vesículas grandes na peça intermediária de Pseudopimelodidae, e a presença de vesículas muito alongadas e dispostas em posição periférica distal em Heptapteridae e mitocôndrias distribuídas em toda a peça intermediária de Pseudopimelodidae e muito próximas ao núcleo em Heptapteridae. Heptapteridae e Pimelodidae compartilham várias características como a espermiogênese do tipo III, o mesmo padrão de condensação da cromatina e a ausência de fossa nuclear e projeções laterais ou fins. O espermatozóide de Pseudopimelodidae é mais similar aos dos Siluridae, porém a ausência de dados adicionais sobre a espermiogênese e o espermatozóide de outros siluriformes ainda limitam uma discussão mais ampla na ordem

Ultrastructure of fresh and post thawed sperm of pejerrey Odontesthes bonariensis (Atheriniformes)

“…Morphological descriptions of sperm as describe above are very useful to establish synapomorphies and phylogenetic relationships between groups as it was used for Mullidae and Siganidae families (Gwo et al, 2004a), or between species of Doradidae (Quagio-Grassiotto et al, 2011). Also, it can be used to describe and compare the spermiogenesis process in some species of Heptapteridae, Pseudopimelodidae, Pimelodidae (Quagio-Grassiotto et al, 2005;Quagio-Grassiotto & Oliveira, 2008) and in some economically important fish species from Sinpercidae family (Luo et al, 2011).…”

Comparative analysis of spermiogenesis and sperm ultrastructure in Callichthyidae (Teleostei: Ostariophysi: Siluriformes)

“…Based on the siluriform spermatozoa described in the literature (Porier & Nicholson, 1982;Kwon et al, 1998;Lee, 1998;Lee and Kim, 1999;Kim & Lee, 2000;Quagio-Grassiotto & Carvalho, 2000;Lee & Kim, 2001;Quagio-Grassiotto et al, 2001;Santos et al, 2001;Burns et al, 2002;Mansour et al, 2002;Quagio-Grassiotto et al, 2005;Spadella et al, 2006a, b), the midpiece size (character 10) was considered short when its total length was < 1.7 µm, and long when its total length was > 1.7 µm. The cytoplasmic channel size (character 12) was considered short when its total length was < 1.5 µm, and long when its total length was > 1.5 µm.…”

“…In the Callichthyinae, sperm production occurs completely within spermatocysts in the germinal epithelium, characterizing this spermatogenesis as the cystic type. This type of spermatogenesis is present in most Teleostei (Mattei et al, 1993;Quagio-Grassiotto et al, 2001;Quagio-Grassiotto et al, 2003;Quagio-Grassiotto et al, 2005).…”

“…In Pimelodidae and Heptapteridae, the flagellum is medial, the nucleus does not rotate, and both the nuclear fossa and the cytoplasmic channel are absent during spermiogenesis, characterizing a third type of spermiogenesis (Quagio-Grassiotto et al, 2005;Quagio-Grassiotto & Oliveira, 2007). The process of spermiogenesis observed in Corydoradinae is characterized by an eccentric development of the flagellum, the absence of nuclear rotation, formation of an eccentric nuclear fossa, formation of a cytoplasmic channel formation, and the absence of centriolar migration.…”

Spermiogenesis particularities of a sperm storage species: <i>Helicolenus dactylopterus</i> (Teleostei: Scorpaenidae)

“…However, nuclear rotation may be incomplete, and in this case the flagellum is eccentric to the nucleus and spermatozoa are of an intermediate type between I and II. Recent studies of Pimelodidae (Quagio-Grassiotto and Oliveira, in press) and Heptapteridae (Quagio-Grassiotto et al, 2005) show a medial flagellar development, in which there is no nuclear rotation. These characteristics have not been found in other fish species until now, so QuagioGrassiotto et al (2005) postulated a new type of spermiogenesis, which they called type III.…”