Spermatophore formation in the pseudoscorpion Chthonius ischnocheles (Chthoniidae)

The reproduction of pseudoscorpions involves indirect sperm transfer by means of spermatophores. The spermatophores are the product of the male genital atrium. A functional interpretation of spermatophore formation in Chthonius ischnocheles is based on evidence from (a) a morphological study of the genital atrium, the associated accessory glands and the musculature (b) males sectioned during spermatophore production (c) histochemical tests on the glands and their secretions (d) biochemical analyses of one gland (posterior dorsal) and its secretion (e) the behaviour of males during this process and (f) the structure of the spermatophore.
The anterior region of the genital atrium is concerned with the production of the sperm packet. The encysted sperm and the seminal fluid from the prostatic reservoir are encapsulated in a sperm packet by a secretion from two pairs of anterior glands. The posterior region of the genital atrium is responsible for the formation of the spermatophore stalk and its distal elaboration, the two lateral collars. These parts of the spermatophore arise from the fibroin secretion of the posterior dorsal gland; the shape of the spermatophore collars is correlated with their mould, the medial diverticula. In addition the lateral glands secrete a light oil which accumulates on a thickening of the spermatophore stalk proximal to the collars. This suggested that this secretion acts as a pheromone to attract females to the spermatophore since in this species males produce their spermatophores in the absence of females.