Fig. 4

Libinia spinosa, females. a General view of the spermatheca containing degenerating spermatozoids (sp), enclosed by spermathecal secretions (ss), holocrine gland cells (hgc) and a multistratified epithelium (ep). b Detailed structure of degenerating spermatozoids (arrows) inside spermathecae. c General view of a spermatheca full of well-developed spermatozoids (sp), surrounded by spermathecal secretions (ss), holocrine gland cells (hgc) and a multistratified epithelium (ep). d Detailed structure of well-developed spermatozoids encountered inside spermathecae, characterized by a rounded form and an acrosomal core distinguishable (arrows)