Family: Zetomimidae
Taxonomy: This is the only species in this genus found at La Selva, and is described in Behan-Pelletier (1998). Adults are a fairly large size for oribatid mites, being almost 0.6mm in length. This species shows sexual dimorphism which is rare in Oribatida. The entire ventral and anal plates of the male are porose other than a small band of integument between the genital and anal plate. In contrast, female ventral and anal plates are without porose regions. This distinct sexual dimorphism, discussed in Norton and Alberti (1997), possibly plays a role in intraspecific communication, with the male producing semiochemicals (sex-attractants or general aggregation pheremones) that are involved in reproductive biology.
Habitat: This is among the few oribatid species found in the water in the experimental swamp at La Selva. Adults are easily collected by extracting handfuls of wet vegetation from on and in the water in the swamp in Berlese funnels. This species has never been collected in the swamp during dry periods when there is no available free-standing water. Neither has it been collected from riparian habitats, such as that at Sendero Tres Rios 4000. All known species in the genus are associated with aquatic habitats.
Ecology: Members of this species probably graze algae and fungi on the leaves of aquatic plants.
Reference:
Behan-Pelletier VM 1998. Ceratozetoidea (Acari: Oribatida) of lowland tropical rainforest, La Selva, Costa Rica. Acarologia 39: 349-381.
Norton RA and Alberti G. 1997. Porose integumental organs of oribatid mites (Acari, Oribatida). 3. Evolutionary and ecological aspects. Zoologica. 146:115-143.