INTEGUMENTAL GLANDS OF THE TICK RHIPICEPHALUS-APPENDICULATUS (ACARI, IXODIDAE) AS POTENTIAL PRODUCERS OF SEMIOCHEMICALS

The opisthosomal integument and associated secretory organs of Rhipice phalus appendiculatus Neumann larvae, nymphs, females and males, both unfed and fed were examined by light and electron microscopy. Type 1 d ermal glands were found on the alloscutum and scutum of all ticks. The y were undeveloped in unfed ticks and reached full development in engo rging ticks. They produced secretory granules from 2 glandular cells b ut without accumulation of a reservoir of secreted material. Type 2 de rmal glands were found in all ticks, with pores on the alloscutum, edg e of scutum, and on anal plates. These glands produced secretion durin g feeding and accumulated large reservoirs of secreted material that w ere present in engorging, recently detached and questing ticks. Spirac ular glands were found in all ticks below the spiracle plate. They pro duced small amounts of secretion and had pores to the exterior by way of spiracle goblets. No obvious cycle of secretory activity was record ed. Foveal glands were present and produced secretions in nymphs, fema les, and males. They were largest in females with an accumulation of s ecretory vesicles in feeding ticks. The potential function of these gl ands is discussed in the context of the chemical ecology of this tick.