Department of Biology,Wenzhou Medical College,Zhejiang 325027,China 2.School of Life and Environmental Sciences,Wenzhou Normal College,Wenzhou 325027,China
We studied the ultrastructure of epididymal spermatozoa of Eumeces elegans.After epididymal tissues of E.elegans were double fixed with 2.5% glutaric dialdehyde and 1% osmic acid,the ultrathin section were observed under H-600 transmission electron microscopy.The spermatozoa contain two major components,a head and a tail.The head contains an acrosomal complex and a nucleus,and the tail a neck,a midpiece,a principal piece and an endpiece.The mature spermatozoa are characterized by:a depressed acrosome at the anterior portion;an acrosomal vescile divided into cortex and medulla;a subacrosomal cone filled with paracrystalline subacrosomal material;a pointed prenuclear perforatorium;a stopper-like perforatorium base plate;an elongated nucleus;an epinuclear lucent zone;rounded nuclear shoulders;a coned nuclear fossa;a bilateral stratified laminar structure within neck region;absence of a endonuclear canal;a long axis of the proximal centriole almost vertical to that of the distal centriole;nine peripheral dense fibres connecting inward with the corresponding 9 triplets of the distal centriole,and backward with the doublets of the axoneme;central fibres connecting with the two central singlets;a short midpiece;columnar mitochondria with linear cristae;each intermitochondrial ring structure consisting of the complete ring of small regularly ovoid or small trapezoid dense bodies;a fibrous sheath into the midpiece;an annulus closely attached to the inner surface of the plasma membrane;the arrangement pattern of the ring structure and mitochondria in rs1/mi1,rs2/mi2,rs3/mi3,and rs4/mi4;mitochondria in order of 10 in transverse section;a thin zone of cytoplasm at the anterior portion of the principal piece;the enlarged fiber 3 and fiber 8 disappearing at the anterior portion of the principal piece;the axoneme complex having an usual 9+2 pattern.The sperm ultrastructure of E.elegans is similar to that of the species within the Sphenomorphus and the Egernia groups,but evidence of spermatozoal autapomorphies is not found in E.elegans.