The Spermathecal Duct of Earwig Doru luteipes (Dermaptera: Forficulidae) Contributes to Spermatozoa Survival

Abstract

The spermatheca of female insects is responsible for storing spermatozoa until fertilization. In Dermaptera, there are anatomical data for the spermatheca, but the histology is still unknown. This study describes the anatomy, histology, and hystochemistry of the Doru luteipes (Scudder) (Dermaptera: Forficulidae) spermatheca. The D. luteipes spermatheca is a single structure with an enlargement (reservoir) opening through a sinuous duct. The epithelial cells of the reservoir, and those of the duct, are different throughout the organ. These cells are rich in neutral polysaccharides, glycoconjugates, and proteins, indicating that the secretions function in the maintenance of spermatozoa viability. Muscles occur both in the reservoir and the duct, an uncommon feature in the spermatheca of other insects. This is the first histological description of the D. luteipes spermatheca, showing that both the duct and reservoir epithelial cells contribute compounds to maintain the spermatozoa.