open access
메뉴
open access
메뉴
ISSN : 1225-3480
Some characteristics of the formations of acrosomal vesicles during the late stage of spermatids during spermiogenesis and taxonomical charateristics of sperm morphology in male two species (Saxidomus purpurata and Meretrix petechialis) in the family Veneridae were investigated by electron microscope observations. In two species, the morphologies of the spermatozoa have the primitive type and are similar to those of other bivalves in that it contains a short midpiece with five mitochondria surrounding the centrioles. The morphologies of the sperm nuclear types of S. purpurata and M. petechialis in Veneridae have the curved cylindrical and cylinderical type, respectively. And the acrosome shapes of two species are the same cap-shape type. In particular, the axial filament is not found in the lumen of the acrosome of two species, however, subacrosomal granular materials are observed in the subacrosomal spaces between the anterior nuclear fossa and the acrosomal vesicle of two species. The spermatozoon of S. purpurata is approximately 46-52 µm in length, including a curved sperm nucleus (about 3.75 µm in length), a long acrosome (about 0.40 µm in length),and a tail flagellum (about 45-47 µm long). And the spermatozoon of M. petechialis is approximately 47-50 μm in length including a slightly curved sperm nucleus (about 1.50μm in length), an acrosome (about 0.56 μm in length) and tail flagellum (44-48 μm in length). In two species, the axoneme of the sperm tail flagellum of each species consists of nine pairs of microtubules at the periphery and a pair of cental doublets at the center. Therefore, the axoneme of the sperm tail flagellum shows a 9 + 2 structure. In particular, taxonomically important some charateristics of sperm morphologies of two species in the family Veneridae are acrosomal morphology of the sperm, The axial filament is not found in the acrosome as seen in a few species of the family Veneridae in the subclass Heterodonta. The acrosomal vesicle is composed of right, left basal rings and the apex part of the acrosomal vesicle. In particular, right and left basal rings show electron opaque part (region), while the apex part of the acrosomal vesicle shows electron lucent part (region). These charateristics belong to the subclass Heterodonta, unlikely a characteristic of the subclass Pteriomorphia showing all part of the acrosome being composed of electron opaque part (region). Therefore, it is easy to distinguish the families or the subclasses by the acrosomal structures. The number of mitochondria in the midpiece of the sperm of S. purpurata and M. petechialis in Veneridae are five. However, the number of mitochondria in the midpiece of the sperm in most species of Veneridae in the subclass Heterodonta are four. Therefore, the number of mitochondria of the sperm midpiece of two species are exceptionally 5, and it is only exceptional case in the species in Veneridae in the subclass Heterodonta. Except these cases, the number of mitochondria in the sperm midpiece in all families in the subclass Heterodontaare are 4, and now widely used in taxonomic analyses.
Chung, E.Y., Lee, T.Y. and An, C.M. (1991) Sexual maturaration of the venus clam, Cyclina sinensis, on the west coast of Korea. Journal of Medical and Applied Malacology, 3: 125-136.
Chung, E.Y. and Ryou, D.K. (2000) Gametogenesis and sexual maturation of the surf clam Mactra venerifermis on the west coast of Korea. Malacologia, 42: 149-163.
Chung, E.Y., Kim, E.J. and Park, G.M. (2007) Spermatogenesis and sexual maturation in male Mactra chinensis (Bivalvia: Mactridae) of Korea. Integrative Bioscience, 11: 227-234.
Chung, E.Y., Chung, C.H., Kim, J.H., Park, S.W. and Park, K.H. (2010) Ultrastructures of germ cells and the accessory cells during spermatogenesis in male Gomphina veneriformis (Bivalvia: Veneridae) on the East Sea of Korea. Korean Journal of Malacology, 26: 51-62.
Eckelbarger, K.J., Bieler, R., and Mikkelsen, P.M. (1990) ltrastructure of sperm development and mature sperm morphology in three species of commensal bivalves (Mollusca: Galeommatoidea). Journal of Morphology, 205: 63-75.
Eckelbarger, K.J. and Davis, C.V. (1996) Ultrastructure of the gonad and gametogenesis in the eastern oyster, Crassostrea virginica. II. Testis and spermatogenesis. Marine Biology, 127: 89-96.
Franzén, Å. (1970) Phylogenetic aspects of the mophology spermatozoa and spermiogenesis. In; Baccetti B (ed) "Comparative spermatology.". Accademia Nationale Dei Lincei, Rome, pp. 573.
Franzén, Å. (1983) Ultrastructural studies of spermatozoa in three bivalve species with notes on evolution of elongated sperm nucleus in primitive spermatozoa. Gamete Research, 7: 199-214.
Gaulejac, de J., Jenry, M. and Vicente, N. (1995) An ultrastructural study of gametogenesis of the marine bivalve Pinna nobilis (Linnaeus, 1758). II. Spermatogenesis. Journal of Molluscan Studies, 61: 393-403.
Healy, J.M. (1989) Spermiogenesis and spermatozoa in the relict bivalve genus Neotrigonia: relevance to trigonioid relationships, particularly Unionoidea. Marine Biology, 103: 75-85.
Healy, J.M. (1995) Sperm ultrastructure in the marine bivalve families Carditidae and Crassatellidae and and its bearing on unification of the Crasssatelloidea with the Carditoidea. Zoological Science, 24: 1-28.
Healy, J.M. and Lester, R.J.G. (1991) Sperm ultrastructure in the Australian oyster Saccostrea commercialis (Iredale and Roughley) (Bivalvia: Ostreidea), Journal of Molluscan Studies. 57: 219-224.
Hodgson, A.N. and Bernard, R.T.F. (1986) Ultrastructure of the sperm and spermatogenesis of three species of Mytilidae (Mollusca, Bivalvia). Gamete Research, 15: 123-135.
Kim, J.H. (2001) Spermatogenesis and comparative ultrastructure of spermatozoa in several species of Korean economic bivalves (13 families, 34 species). Pukyung National University 161 pp.
Kim, J.H., Chung, E.Y., Choi, K.H., Park, K.H. and Park, S.W. (2010a) Ultrastructure of germ cells during spermatogenesis and some characteristics of sperm morphology in Male Mytilus coruscus (Bivalvia: Mytilidae) on the west coast of Korea. Korean Journal of Malacology, 26: 33-43.
Kim, J.H., Chung, E.Y., Choi, K.H., Lee, K.Y. and Choi, M.S. (2010b) Ultrastructure of the testis and germ cell development during spermatogenesis in male Crassostrea gigas (Bivalvia: Ostreidae) in western Korea. Korean Journal of Malacology, 26: 235-244.
Kim, J.H., Park, Y.J., Lee, K.Y., Choi, M.S., Seo, W.J. and Chung, E.Y. (2010c) Germ cell differentiations during spermatogenesis and ultrastructural characteristics of mature sperms in male Protothaca (Notochione) jedoensis (Bivalvia: Veneridae). Development and Reproduction, 14: 269-279.
Kim, J.H., Chung, E.Y., Lee, K.Y., Choi, M.S. Seo, W.J. and Kim. S.H. (2010d) Spermatid Differentiations during spermiogenesis and mature sperm ultrastructure in male Crassostrea niponica (Seki, 1934) (Pteriomorphia: Ostreidae). The Korean Journal of Malacology, 26: 311-316.
Popham, J.D. (1974) Comparative morphometrics of the acrosomes of the sperms of externally and internally fertilizing sperms of the sperms of the shipworms (Teredinidae, Bivalvia, Mollusca). Cell Tissue Research. 150: 291-297.
Popham, J.D. (1979) Comparative spermatozoon morphology and bivalve phylogeny. Malacological Review, 12: 1-20.