Fine structure of the synganglion of unfed female Rhipicephalus (Rhipicephalus) sanguineus (Latreille) (Ixodoidea: Ixodidae).

The synganglion of unfed female Rhipicephalus (Rhipicephalus) sanguineus (Latreille) is enclosed within a well defined neural lamella underlined by the perineurium. No organelles were observed in the neural lamella, whereas axons containing neurosecretory vesicles, tracheal elements and glycogen deposits are visible in the perineurium. Below the perineurium, a cortical layer of nervous and non-nervous elements surrounds an inner neuropile, the latter is enclosed by a thin subperineurial layer. The neuropile is formed of nerve fibers containing neurotubules.