The sclerotized spermatophore of the barklouse Lepinotus patruelis.

Lepinotus patruelis Pearman (Psocoptera: Trogiidae) has a very unusual spermatophore that is a permanent, hardened structure which is deposited and retained in the spermatheca. This study elaborates on the structure of the spermatophore, shows for the first time that the spermatophore is sclerotized, and provides information on its composition and development over time. The spermatophore is produced within the ventral seminal vesicles, and transferred to the female as a semi-solid, bullet shaped object. It is composed of five lamina which undergo several transformations during the first 24 h after copulation. A sample of three newly formed spermatophores were found to contain 18, 40 and 55 sperm. The possible function of the sclerotized spermatophore wall is discussed.