Premium
Sperm structure in the scissurellid gastropod Sinezona sp. (Prosobranchia, Pleurotomarioidea)
Author(s) -
HEALY JOHN M.
Publication year - 1990
Publication title -
zoologica scripta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.204
H-Index - 64
eISSN - 1463-6409
pISSN - 0300-3256
DOI - 10.1111/j.1463-6409.1990.tb00254.x
Subject(s) - axoneme , biology , anatomy , flagellum , annulus (botany) , prosobranchia , spermatozoon , sperm , spermiogenesis , acrosome , nucleus , ultrastructure , microbiology and biotechnology , zoology , mollusca , semen , paleontology , botany , bacteria
Spermatozoa of Sinezona sp. (Scissurcllidac) arc examined ultrastructurally and compared with spermatozoa of other vetigastropods. Sinezona sperm are characterized by the following features: (1) a squat‐conical acrosomal vesicle; (2) subacrosomal deposits–one forming a perinuclear sheath and the second forming a rod which almost penetrates the nucleus; (3) prominent nuclear invaginations enclosing the axial rod and centriolar regions; (4) a midpiece consisting of axoneme surrounded by a single, sleeve‐like mitochondrion; (5) an annulus occurring posterior to the midpiece; and (6) a flagellum. Spermatozoa of Sinezona sp. are clearly modified in structure in comparison with spermatozoa of other pleurotomarioids and, more generally, most other vetigastropods (these retain multiple, spherical mitochondria and, with rare exceptions, do not have the ccntrioles located in a nuclear invagination).