Ultrastructure of the sperm of Aplysia Californica Cooper

Main Article Content

Jeffrey S Prince Brian Cichocki


The structure of the sperm of Aplysia californica was studied by both transmission and scanning electron microscopy.  Aplysia californica, a species with internal fertilization, has the modified type of molluscan sperm structure.  Spermatids had a glycogen helix spiraled about the flagellum, both enclosed by a common microtubular basket.  A second vacuole helix was periodically seen only in spermatids and absent in spermatozoa.  An additional basket of microtubules appeared to direct the elongation and spiraling of the nucleus about the flagellum/glycogen helix. A flat acrosome was present while the centriolar derivative was embedded in a deep nuclear fossa with strands of heterochromatin arranged nearly perpendicular to its long axis.  The mitochondrial derivative consisted of small, frequently electron dense, closely spaced rods but individual mitochondria were also seen surrounding the axoneme of spermatids.  The axoneme consisted of dense fibers that appeared to have a "C" shape substructure with a central dense fiber thus providing a 9+1 arrangement of singlet units; the typical 9+2 microtubule arrangement of flagella was absent. Flagella with two axonemes were frequently seen as well as an extra axoneme within the head of immature sperm.

Article Details

How to Cite
PRINCE, Jeffrey S; CICHOCKI, Brian. Ultrastructure of the sperm of Aplysia Californica Cooper. Medical Research Archives, [S.l.], n. 2, mar. 2015. ISSN 2375-1924. Available at: <https://www.journals.ke-i.org/index.php/mra/article/view/36>. Date accessed: 22 june 2018.
sperm; ultrastructure
Research Articles


ANDERSON, W. A. & PERSONNE, P. 1976. The molluscan spermatozoon: Dynamic aspects of its structure and function. American Zoologist, 16:293-313.

BEEMAN, R. D. 1977. Gastropoda: Opisthobranchia. In Reproduction of marine Invertebrates Vol 1V:115-172. (Giese, A. C. and Peearse, J. S. eds.) Academic Press, New York.

BOZZO, M. G. RIBES, E. SAGRISTA, E. POQUET, M. & DURFORT, M. 1993. Fine structure of the spermatozoa of Crassostrea gigas (Mollusca, Bivalvia). Molecular Reproduction and Developement, 34:206-211.
Coelho, L., Prince, J. and Nolen, T.G. 1998. Processing of Defensive Pigment in Aplysia californica: Acquisition, Modification and Mobilization of the Red Algal Pigment, R-Phycoerythrin by the Digestive Gland. J. Exper. Biol. 201:425-438.

FRANZEN, A. 1955. Comparative morphological investigations into the spermiogenesis among Mollusca. Zoologiska Bidrag Uppsala, 30:399-456.

GWO, J. -C. YANG, W. -T. SHEU, Y. -T. & CHENG, H. -Y. 2002. Spermatozoan morphology of four species of bivalve (Heterodonta, Veneridae) from Taiwan. Tissue and Cell, 34:39-43.

HEALY, J. M. 1988. The ultrastructure of the spermatozoa and spermiogenesis in pyramidellid gastropods, and its systematic importance. Helgolander Meeresunters, 42:303-318.

Healy, J. M. 1990. Spermatozoa and spermatogenesis of Cornirostra, Valvata and Orbitestella (Gastropoda: Heterobranchia) with a discussion of Valvatoidean sperm morphology. Jounral of Molluscan Studies. 56: 557-566.

Healy, J. M. 1991. Sperm morphology in the marine gastropod Architectonica perspectiva (Mollusca): unique features and systematic relevance. Marine Biology 109: 59-65.

HEALY, J. M. 1993. Comparative sperm ultrastructure and spermiogenesis in basal heterobranch gastropods (Valvatoidea, Architectonicoidea Rissoelloidea, Omalogyroidea, Pyramidelloidea) (Mollusca). Zoologica Scripta, 22:263-276.

HEALY, J. M. 1996. Molluscan sperm ultrastructure: correlation with taxonomic units within the Gastropoda, Cephalopoda and Bivalvia. In: Origin and Evolutionary Radiation of the Mollusca. (Taylor, J. D. ed.) 99-113. Oxford University Press, Oxford.

HEALY, J. M. 2001. Spermatogenesis and Oogenesis. In: The Biology of Terrestrial Molluscs. (Baker, G. M. ed.) 357-382. CAB International

HEALY, J. M. & WILLAN, R. C. 1984. Ultrastructure and phylogenetic significance of notaspidean spermatozoa (Mollusca, Gastropoda, Opisthobranchia). Zoologica Scripta, 13:107-120.

HODGSON, A. N. HELLER, J. & BERNARD, R. T. F. 1990. Ultrastructure of the sperm and spermatogenesis in five South African species of the trochid genus Oxystele (Mollusca, Prosobranchia). Molecular Reproduction and Development, 25:263-271.

Kandel, E. R. 1979. Behavorial Biology of Aplysia. A Contibution to the Comparative Study of Opisthobranch Molluscs, W. W. Freeman, San Francisco, Calif, USA.

KUBO, M. & ISHIKAWA, M. 1981. Organization of the acrosome and helical structures in sperm of the Aplysiid, Aplysia kurodai (Gastropoda, Opisthobranchia). Differentiation, 20:131-140.

THOMAS, R. F.1975. The reproductive system of Bursatella leachi plei (Opisthobranchia: Aplysiacea) with special reference to its histology. Malacologia 15:113-131.

Prince, J. S. 2003. A presumptive alphavirus in the gastropod mollusc, Aplysia californica. Bulletin of Marine Science 73(3):673-677.

THOMPSON, T. E. 1973. Euthyneuran and other molluscan spermatozoa. Malacologia, 14:167-206.

THOMPSON, T. E. & BEBBINGTON, A. 1969. Structure and function of the reproductive organs of three species of Aplysia (Gastropoda: Opisthobranchia). Malacologia, 7:347-380.

VITA, P. CORRAL, L. & AZEVEDO, C. 2001. New ultrastructural aspects of the spermatozoon of Aplysia depilans (Gastropoda, Opisthobranchia). Journal of Submicroscopic Cytology and Pathology, 33:165-171.

YING, X. -P. YANG, W. -X. JIANG, N -C. & ZHANG, Y -P. 2004. Ultrastructure of spermatozoa of Bullacta exarata (Philippi) and its significance on reproductive evolution and physio-ecological adaptation. Journal of Zhejand University SCIENCE, 5:1211-1217.

Most read articles by the same author(s)

Obs.: This plugin requires at least one statistics/report plugin to be enabled. If your statistics plugins provide more than one metric then please also select a main metric on the admin's site settings page and/or on the journal manager's settings pages.