Revealing the diversity of a once small taxon: the genus Selenoribates (Acari, Oribatida, Selenoribatidae)

Abstract. Three new intertidal oribatid species, Selenoribates elegans sp. n., Selenoribates quasimodo sp. n. and Selenoribates satanicus sp. n. are described from the archipelago of Bermuda. Selenoribates elegans sp. n. is characterized by its slender body shape, Selenoribates quasimodo sp. n. possesses a hunchback in lateral view and Selenoribates satanicus sp. n. exhibits two horn-like projections on its anterior gastronotic region. Based on these new findings, the number of Selenoribates species doubled at once and the distribution of this genus, formerly limited to the Mediterranean and the Red Sea, includes now occurrences in the Atlantic and Indo-pacific Ocean as well. The morphology of Selenoribates quasimodo sp. n. and Selenoribates satanicus sp. n. deviates conspicuously from the other known members of Selenoribates, thus indicating that not only the number of species but also the anatomy of this genus is more diverse than formerly supposed. Nymphs of Selenoribates quasimodo sp. n. show an interesting case of ontogenetic neotrichy, with gastronotic setae being duplicated with each moult.