Spermiogenesis and Reproductive Biology of Dermanyssus gallinae (DeGeer) (Parasitiformes: Dermanyssidae)

Mating behavior, spermiogenesis, egg development time, and male mating capacity of Dermanyssus gallinae (DeGeer) (Parasitiformes: Dermanyssidae) are described. Insemination is podospermal, via spermadactyls inserted into sperm induction pores located on each side of the body (podosoma) near the posterior of coxae III. Mating behavior is of the Amblyseius-Typhlodromus type, requiring 14 min to 1 h. One or both sperm induction pores may be used. Spermatophores isolated during mating were spherical, translucent, permeable to stain, and approximately 200 μm in diameter with a smaller neck where they were held by male chelicerae. Observation and measurement of approximately 200 spermatozoa from male reproductive tracts, spermatophores, and unfed and fed mated females indicate that spermatozoa in this species do not develop beyond irregularly rounded nonpolar cells with granular cell membranes, agranular cytoplasm, and large, densely stained nuclei with average cellular and nuclear dimensions of 7.80 by 11.73 and 3.70 by 4.09 μm, respectively. Several spermatozoa were observed in medial ovarian tissue of unfed females 1d after mating, and spermatozoa were not found in five unfed females 32 d after mating. Egg maturation and protonymphal development appear staggered, not synchronous. Males probably are incapable of successfully inseminating more than three or four females in the same number of days.