| abstract | The oribatid mite superfamily Ceratozetoidea is poorly represented in the Neotropics of Central America. Nine species in seven genera, representing four families, were recorded from a variety of habitats in primary and secondary lowland tropical rainforest at Estacion Biologica La Selva, Heredia, Costa Rica. Seven of these species are new to science and are described on the basis of adult specimens: Selvazetes sylvanus n. gen., n.sp., Allozetes alas n.sp., (Mycobatidae); Lamellobates reticulatus n.sp., Paralamellobates striatus n.sp. (Austrachipteriidae); Heterozetes heleios n.sp., Zetomimus naias n.sp., (Zetomimidae) and Ceratozetes ambiguus n.sp. (Ceratozetidae). A table presents the key differences between these nine ceratozetoid species. Heterozetes heleios and Zetomimus naias are sexually dimorphic with most of the anal plates and ventral plate porose in males, but not in females. Similar sexual dimorphism exists in Z. cristatus (Hammer), known from Argentina. I discuss the synonymy of Hamobates with Zetomimus, and the placement of Allozetes in Mycobatidae. |