The spermatozoon ultrastructure of left-eye flounder, Paralichthys olivaceus, was observed by electronic microscopy, and shown to consist of head, midpiece and tail. Some nuclear vacuoles were observed inside and alon...The spermatozoon ultrastructure of left-eye flounder, Paralichthys olivaceus, was observed by electronic microscopy, and shown to consist of head, midpiece and tail. Some nuclear vacuoles were observed inside and along the outer part of the nucleus and double-membrane structures were observed between the nuclear membrane and plasma membrane. The sperm sleeve consisted of four independent parts and had more than four mitochondria. Along the sperm tail there were wing-like lateral fins.展开更多
The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this f...The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this family of the Rhachiglossa is controversial. We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy. These species are considered to be representatives of two subfamilies, two genera, and 10 subgenera. Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species. We found no support for the subgeneric differentiation of the species. However, the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions. We noted sexual dimorphism in the shape of the teeth in some species, and considerable variability of the shape of teeth within a single species. Based on our results, the genus Nassarius cannot be split into subgenera using radula morphology.展开更多
文摘The spermatozoon ultrastructure of left-eye flounder, Paralichthys olivaceus, was observed by electronic microscopy, and shown to consist of head, midpiece and tail. Some nuclear vacuoles were observed inside and along the outer part of the nucleus and double-membrane structures were observed between the nuclear membrane and plasma membrane. The sperm sleeve consisted of four independent parts and had more than four mitochondria. Along the sperm tail there were wing-like lateral fins.
基金Supported by the National Natural Science Foundation of China (No. 41076104)the Knowledge Innovation Program of Chinese Academy of Sciences (No. KSCX2-YW-Z-0916)the Knowledge Innovation Program of Institute of Oceanology, Chinese Academy of Sciences (No. 2007-12)
文摘The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this family of the Rhachiglossa is controversial. We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy. These species are considered to be representatives of two subfamilies, two genera, and 10 subgenera. Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species. We found no support for the subgeneric differentiation of the species. However, the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions. We noted sexual dimorphism in the shape of the teeth in some species, and considerable variability of the shape of teeth within a single species. Based on our results, the genus Nassarius cannot be split into subgenera using radula morphology.
