Ultrastructural observations on matine sperm of Pomphorhynchus laevis (Müller, 1776), the dominant acanthocephalan parasite of fish from the River Brenta, were carried out by scanning (SEM) and transmission electron microscopy (TEM). Adult males of P. laevis were obtained from the digestive tract of Leuciscus cephalus (Pisces: Cyprinidae). The spermatozoon of P. laevis is inverted with respect to conventional sperm models; it is filiform and consists of an anterior flagellar apparatus and a posterior nucleocytoplasmic derivative. The latter includes a layer of condensed chromatin beneath the plasma membrane opposite to the flagellum, numerous large subspherical electron dense inclusions, glycogen deposits and a pentalaminar structure next to the flagellum. The nucleocytoplasmic derivative terminates caudally with a flat lamina devoid of the dense inclusions and glycogen deposits. Proceeding through the posterior lamina, the 9 + 2 axoneme progressively disorganizes. The ultrastructural ...
Ultrastructural study of mature sperm of pomphorhynchus laevis muller (Acanthocephala: Palaeacanthocephala), a fish parasite
SAYYAF DEZFULI, Bahram
1995
Abstract
Ultrastructural observations on matine sperm of Pomphorhynchus laevis (Müller, 1776), the dominant acanthocephalan parasite of fish from the River Brenta, were carried out by scanning (SEM) and transmission electron microscopy (TEM). Adult males of P. laevis were obtained from the digestive tract of Leuciscus cephalus (Pisces: Cyprinidae). The spermatozoon of P. laevis is inverted with respect to conventional sperm models; it is filiform and consists of an anterior flagellar apparatus and a posterior nucleocytoplasmic derivative. The latter includes a layer of condensed chromatin beneath the plasma membrane opposite to the flagellum, numerous large subspherical electron dense inclusions, glycogen deposits and a pentalaminar structure next to the flagellum. The nucleocytoplasmic derivative terminates caudally with a flat lamina devoid of the dense inclusions and glycogen deposits. Proceeding through the posterior lamina, the 9 + 2 axoneme progressively disorganizes. The ultrastructural ...I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
