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Ultrastructure of spermiogenesis in Plagioscion squamosissimus (Teleostei, Perciformes, Sciaenidae)
(Churchill Livingstone, 2014)
Ultrastructure of spermiogenesis in Plagioscion squamosissimus (Teleostei, Perciformes, Sciaenidae)
(Churchill Livingstone, 1999-12-01)
Spermiogenesis in Plagioscion squamosissimus occurs in cysts. It involves a gradual differentiation process of spermatids that is characterized mainly by chromatin compaction in the nucleus and formation of the flagellum, ...
Spermatogonia and spermatocyte ultrastructure in Hoplias malabaricus (Teleostei, Characiformes : Erythrinidae)
(Cambridge University Press, 2002-07-01)
The Hoplias malabaricus primary spermatogonium shows a large nucleus, central nucleolus, and low electron-dense cytoplasm containing nuages. In cysts, they undergo several mitotic divisions with incomplete cytokinesis, ...
The ultrastructure of Sorubim lima (Teleostei, Siluriformes, Pimelodidae) spermatogenesis: premeiotic and meiotic periods
(Churchill Livingstone, 1999-12-01)
The ultrastructure of Sorubim lima spermatogenesis during the premeiotic and meiotic periods was studied. Our observations showed that the germ cells in the cysts are connected by cytoplasmic bridges and the mitotic and ...
Karyotype variability in eight species of the subfamilies Loricariinae and Ancistrinae (Teleostei, Siluriformes, Loricariidae)
(2003-01-01)
Loricariidae is one of the largest fish families of the world, with about 650 species separated into six subfamilies. To date, cytogenetic data on only 56 species of this family are available. In the present study, the ...
Revision of the South American freshwater genus Plagioscion (Teleostei, Perciformes, Sciaenidae)
(2005-11-15)
The South American freshwater sciaenid genus Plagioscion is reviewed. Five of the 15 nominal species assigned to the genus are considered to be valid: Plagioscion squamosissimus, widely distributed in Atlantic drainages ...