New Fortuyniidae and Selenoribatidae (Acari, Oribatida) from Bonaire (Lesser Antilles) and morphometric comparison between Eastern Pacific and Caribbean populations of Fortuyniidae

Two new intertidal oribatid mite species were found on the coast of Bonaire. Litoribates bonairensis sp. nov. can be distinguished from its only congener, L. caelestis, by the cerotegumental pattern and shape of sensillus. This is also the first record of the genus from the Caribbean region. Thasecazetes falcidactylus gen. nov., sp. nov. is characterized by conspicuous longitudinal notogastral ridges and sickle shaped claws and represents a new selenoribatid genus that probably shows a wider distribution within the Caribbean. Both species were found in mangrove habitats. An ecological preference for this environment may be considered. A morphometric investigation of Litoribates and Alismobates populations from the Galápagos Archipelago in the Eastern Pacific, several Caribbean areas and the Western Atlantic Bermuda Islands revealed certain remarkable facts: First, Litoribates species show a conspicuous higher size variation between the different locations than Alismobates species; second, the geographic distance between the populations is reflected in the extent of divergence and third, similar variation patterns shown in Litoribates and Alismobates indicate that both taxa have experienced similar evolutionary histories in the respective geographic regions. An additional molecular genetic analysis provides barcoding sequences for the new taxa and confirms their taxonomic distinctness.