<title language="eng">Study of chelicerae in the tick Amblyomma cajennense (Fabricius 1787) by scanning electron microscopy

Chelicerae de Amblyomma cajennense foram examinados em microscopia de varredura. Esta técnica mostrou detalhes não evidenciáveis ao poder de resolução do microscópio ótico.The structure of the chelicerae was studied with seanning electron microscope in the tick Amblyomma cajennense (Fabricius, 1787). Lamellar organs were seen at the basis of the digits of the chelicerae. Considerations on the palaeontologic origin of ticks and Acari are made with reference to literature